Google Git
Sign in
android / toolchain / jdk / jdk21 / HEAD / . / src / hotspot / share / oops / instanceKlass.cpp
blob: 6f0d521b9d4c3af5bdbec5d069fa6802b7a2921f [file] [log] [blame]
/*
* Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "cds/archiveUtils.hpp"
#include "cds/classListWriter.hpp"
#include "cds/heapShared.hpp"
#include "cds/metaspaceShared.hpp"
#include "classfile/classFileParser.hpp"
#include "classfile/classFileStream.hpp"
#include "classfile/classLoader.hpp"
#include "classfile/classLoaderData.inline.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/moduleEntry.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/systemDictionaryShared.hpp"
#include "classfile/verifier.hpp"
#include "classfile/vmClasses.hpp"
#include "classfile/vmSymbols.hpp"
#include "code/codeCache.hpp"
#include "code/dependencyContext.hpp"
#include "compiler/compilationPolicy.hpp"
#include "compiler/compileBroker.hpp"
#include "gc/shared/collectedHeap.inline.hpp"
#include "interpreter/oopMapCache.hpp"
#include "interpreter/rewriter.hpp"
#include "jvm.h"
#include "jvmtifiles/jvmti.h"
#include "logging/log.hpp"
#include "logging/logMessage.hpp"
#include "logging/logStream.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/iterator.inline.hpp"
#include "memory/metadataFactory.hpp"
#include "memory/metaspaceClosure.hpp"
#include "memory/oopFactory.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/fieldStreams.inline.hpp"
#include "oops/constantPool.hpp"
#include "oops/instanceClassLoaderKlass.hpp"
#include "oops/instanceKlass.inline.hpp"
#include "oops/instanceMirrorKlass.hpp"
#include "oops/instanceOop.hpp"
#include "oops/instanceStackChunkKlass.hpp"
#include "oops/klass.inline.hpp"
#include "oops/method.hpp"
#include "oops/oop.inline.hpp"
#include "oops/recordComponent.hpp"
#include "oops/symbol.hpp"
#include "prims/jvmtiExport.hpp"
#include "prims/jvmtiRedefineClasses.hpp"
#include "prims/jvmtiThreadState.hpp"
#include "prims/methodComparator.hpp"
#include "runtime/arguments.hpp"
#include "runtime/deoptimization.hpp"
#include "runtime/atomic.hpp"
#include "runtime/fieldDescriptor.inline.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/javaThread.inline.hpp"
#include "runtime/mutexLocker.hpp"
#include "runtime/orderAccess.hpp"
#include "runtime/reflectionUtils.hpp"
#include "runtime/threads.hpp"
#include "services/classLoadingService.hpp"
#include "services/finalizerService.hpp"
#include "services/threadService.hpp"
#include "utilities/dtrace.hpp"
#include "utilities/events.hpp"
#include "utilities/macros.hpp"
#include "utilities/stringUtils.hpp"
#include "utilities/pair.hpp"
#ifdef COMPILER1
#include "c1/c1_Compiler.hpp"
#endif
#if INCLUDE_JFR
#include "jfr/jfrEvents.hpp"
#endif
#ifdef DTRACE_ENABLED
#define HOTSPOT_CLASS_INITIALIZATION_required HOTSPOT_CLASS_INITIALIZATION_REQUIRED
#define HOTSPOT_CLASS_INITIALIZATION_recursive HOTSPOT_CLASS_INITIALIZATION_RECURSIVE
#define HOTSPOT_CLASS_INITIALIZATION_concurrent HOTSPOT_CLASS_INITIALIZATION_CONCURRENT
#define HOTSPOT_CLASS_INITIALIZATION_erroneous HOTSPOT_CLASS_INITIALIZATION_ERRONEOUS
#define HOTSPOT_CLASS_INITIALIZATION_super__failed HOTSPOT_CLASS_INITIALIZATION_SUPER_FAILED
#define HOTSPOT_CLASS_INITIALIZATION_clinit HOTSPOT_CLASS_INITIALIZATION_CLINIT
#define HOTSPOT_CLASS_INITIALIZATION_error HOTSPOT_CLASS_INITIALIZATION_ERROR
#define HOTSPOT_CLASS_INITIALIZATION_end HOTSPOT_CLASS_INITIALIZATION_END
#define DTRACE_CLASSINIT_PROBE(type, thread_type) \
{ \
char* data = nullptr; \
int len = 0; \
Symbol* clss_name = name(); \
if (clss_name != nullptr) { \
data = (char*)clss_name->bytes(); \
len = clss_name->utf8_length(); \
} \
HOTSPOT_CLASS_INITIALIZATION_##type( \
data, len, (void*)class_loader(), thread_type); \
}
#define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait) \
{ \
char* data = nullptr; \
int len = 0; \
Symbol* clss_name = name(); \
if (clss_name != nullptr) { \
data = (char*)clss_name->bytes(); \
len = clss_name->utf8_length(); \
} \
HOTSPOT_CLASS_INITIALIZATION_##type( \
data, len, (void*)class_loader(), thread_type, wait); \
}
#else // ndef DTRACE_ENABLED
#define DTRACE_CLASSINIT_PROBE(type, thread_type)
#define DTRACE_CLASSINIT_PROBE_WAIT(type, thread_type, wait)
#endif // ndef DTRACE_ENABLED
bool InstanceKlass::_finalization_enabled = true;
static inline bool is_class_loader(const Symbol* class_name,
const ClassFileParser& parser) {
assert(class_name != nullptr, "invariant");
if (class_name == vmSymbols::java_lang_ClassLoader()) {
return true;
}
if (vmClasses::ClassLoader_klass_loaded()) {
const Klass* const super_klass = parser.super_klass();
if (super_klass != nullptr) {
if (super_klass->is_subtype_of(vmClasses::ClassLoader_klass())) {
return true;
}
}
}
return false;
}
static inline bool is_stack_chunk_class(const Symbol* class_name,
const ClassLoaderData* loader_data) {
return (class_name == vmSymbols::jdk_internal_vm_StackChunk() &&
loader_data->is_the_null_class_loader_data());
}
// private: called to verify that k is a static member of this nest.
// We know that k is an instance class in the same package and hence the
// same classloader.
bool InstanceKlass::has_nest_member(JavaThread* current, InstanceKlass* k) const {
assert(!is_hidden(), "unexpected hidden class");
if (_nest_members == nullptr || _nest_members == Universe::the_empty_short_array()) {
if (log_is_enabled(Trace, class, nestmates)) {
ResourceMark rm(current);
log_trace(class, nestmates)("Checked nest membership of %s in non-nest-host class %s",
k->external_name(), this->external_name());
}
return false;
}
if (log_is_enabled(Trace, class, nestmates)) {
ResourceMark rm(current);
log_trace(class, nestmates)("Checking nest membership of %s in %s",
k->external_name(), this->external_name());
}
// Check for the named class in _nest_members.
// We don't resolve, or load, any classes.
for (int i = 0; i < _nest_members->length(); i++) {
int cp_index = _nest_members->at(i);
Symbol* name = _constants->klass_name_at(cp_index);
if (name == k->name()) {
log_trace(class, nestmates)("- named class found at nest_members[%d] => cp[%d]", i, cp_index);
return true;
}
}
log_trace(class, nestmates)("- class is NOT a nest member!");
return false;
}
// Called to verify that k is a permitted subclass of this class
bool InstanceKlass::has_as_permitted_subclass(const InstanceKlass* k) const {
Thread* current = Thread::current();
assert(k != nullptr, "sanity check");
assert(_permitted_subclasses != nullptr && _permitted_subclasses != Universe::the_empty_short_array(),
"unexpected empty _permitted_subclasses array");
if (log_is_enabled(Trace, class, sealed)) {
ResourceMark rm(current);
log_trace(class, sealed)("Checking for permitted subclass of %s in %s",
k->external_name(), this->external_name());
}
// Check that the class and its super are in the same module.
if (k->module() != this->module()) {
ResourceMark rm(current);
log_trace(class, sealed)("Check failed for same module of permitted subclass %s and sealed class %s",
k->external_name(), this->external_name());
return false;
}
if (!k->is_public() && !is_same_class_package(k)) {
ResourceMark rm(current);
log_trace(class, sealed)("Check failed, subclass %s not public and not in the same package as sealed class %s",
k->external_name(), this->external_name());
return false;
}
for (int i = 0; i < _permitted_subclasses->length(); i++) {
int cp_index = _permitted_subclasses->at(i);
Symbol* name = _constants->klass_name_at(cp_index);
if (name == k->name()) {
log_trace(class, sealed)("- Found it at permitted_subclasses[%d] => cp[%d]", i, cp_index);
return true;
}
}
log_trace(class, sealed)("- class is NOT a permitted subclass!");
return false;
}
// Return nest-host class, resolving, validating and saving it if needed.
// In cases where this is called from a thread that cannot do classloading
// (such as a native JIT thread) then we simply return null, which in turn
// causes the access check to return false. Such code will retry the access
// from a more suitable environment later. Otherwise the _nest_host is always
// set once this method returns.
// Any errors from nest-host resolution must be preserved so they can be queried
// from higher-level access checking code, and reported as part of access checking
// exceptions.
// VirtualMachineErrors are propagated with a null return.
// Under any conditions where the _nest_host can be set to non-null the resulting
// value of it and, if applicable, the nest host resolution/validation error,
// are idempotent.
InstanceKlass* InstanceKlass::nest_host(TRAPS) {
InstanceKlass* nest_host_k = _nest_host;
if (nest_host_k != nullptr) {
return nest_host_k;
}
ResourceMark rm(THREAD);
// need to resolve and save our nest-host class.
if (_nest_host_index != 0) { // we have a real nest_host
// Before trying to resolve check if we're in a suitable context
bool can_resolve = THREAD->can_call_java();
if (!can_resolve && !_constants->tag_at(_nest_host_index).is_klass()) {
log_trace(class, nestmates)("Rejected resolution of nest-host of %s in unsuitable thread",
this->external_name());
return nullptr; // sentinel to say "try again from a different context"
}
log_trace(class, nestmates)("Resolving nest-host of %s using cp entry for %s",
this->external_name(),
_constants->klass_name_at(_nest_host_index)->as_C_string());
Klass* k = _constants->klass_at(_nest_host_index, THREAD);
if (HAS_PENDING_EXCEPTION) {
if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
return nullptr; // propagate VMEs
}
stringStream ss;
char* target_host_class = _constants->klass_name_at(_nest_host_index)->as_C_string();
ss.print("Nest host resolution of %s with host %s failed: ",
this->external_name(), target_host_class);
java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
const char* msg = ss.as_string(true /* on C-heap */);
constantPoolHandle cph(THREAD, constants());
SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
CLEAR_PENDING_EXCEPTION;
log_trace(class, nestmates)("%s", msg);
} else {
// A valid nest-host is an instance class in the current package that lists this
// class as a nest member. If any of these conditions are not met the class is
// its own nest-host.
const char* error = nullptr;
// JVMS 5.4.4 indicates package check comes first
if (is_same_class_package(k)) {
// Now check actual membership. We can't be a member if our "host" is
// not an instance class.
if (k->is_instance_klass()) {
nest_host_k = InstanceKlass::cast(k);
bool is_member = nest_host_k->has_nest_member(THREAD, this);
if (is_member) {
_nest_host = nest_host_k; // save resolved nest-host value
log_trace(class, nestmates)("Resolved nest-host of %s to %s",
this->external_name(), k->external_name());
return nest_host_k;
} else {
error = "current type is not listed as a nest member";
}
} else {
error = "host is not an instance class";
}
} else {
error = "types are in different packages";
}
// something went wrong, so record what and log it
{
stringStream ss;
ss.print("Type %s (loader: %s) is not a nest member of type %s (loader: %s): %s",
this->external_name(),
this->class_loader_data()->loader_name_and_id(),
k->external_name(),
k->class_loader_data()->loader_name_and_id(),
error);
const char* msg = ss.as_string(true /* on C-heap */);
constantPoolHandle cph(THREAD, constants());
SystemDictionary::add_nest_host_error(cph, _nest_host_index, msg);
log_trace(class, nestmates)("%s", msg);
}
}
} else {
log_trace(class, nestmates)("Type %s is not part of a nest: setting nest-host to self",
this->external_name());
}
// Either not in an explicit nest, or else an error occurred, so
// the nest-host is set to `this`. Any thread that sees this assignment
// will also see any setting of nest_host_error(), if applicable.
return (_nest_host = this);
}
// Dynamic nest member support: set this class's nest host to the given class.
// This occurs as part of the class definition, as soon as the instanceKlass
// has been created and doesn't require further resolution. The code:
// lookup().defineHiddenClass(bytes_for_X, NESTMATE);
// results in:
// class_of_X.set_nest_host(lookup().lookupClass().getNestHost())
// If it has an explicit _nest_host_index or _nest_members, these will be ignored.
// We also know the "host" is a valid nest-host in the same package so we can
// assert some of those facts.
void InstanceKlass::set_nest_host(InstanceKlass* host) {
assert(is_hidden(), "must be a hidden class");
assert(host != nullptr, "null nest host specified");
assert(_nest_host == nullptr, "current class has resolved nest-host");
assert(nest_host_error() == nullptr, "unexpected nest host resolution error exists: %s",
nest_host_error());
assert((host->_nest_host == nullptr && host->_nest_host_index == 0) ||
(host->_nest_host == host), "proposed host is not a valid nest-host");
// Can't assert this as package is not set yet:
// assert(is_same_class_package(host), "proposed host is in wrong package");
if (log_is_enabled(Trace, class, nestmates)) {
ResourceMark rm;
const char* msg = "";
// a hidden class does not expect a statically defined nest-host
if (_nest_host_index > 0) {
msg = "(the NestHost attribute in the current class is ignored)";
} else if (_nest_members != nullptr && _nest_members != Universe::the_empty_short_array()) {
msg = "(the NestMembers attribute in the current class is ignored)";
}
log_trace(class, nestmates)("Injected type %s into the nest of %s %s",
this->external_name(),
host->external_name(),
msg);
}
// set dynamic nest host
_nest_host = host;
// Record dependency to keep nest host from being unloaded before this class.
ClassLoaderData* this_key = class_loader_data();
assert(this_key != nullptr, "sanity");
this_key->record_dependency(host);
}
// check if 'this' and k are nestmates (same nest_host), or k is our nest_host,
// or we are k's nest_host - all of which is covered by comparing the two
// resolved_nest_hosts.
// Any exceptions (i.e. VMEs) are propagated.
bool InstanceKlass::has_nestmate_access_to(InstanceKlass* k, TRAPS) {
assert(this != k, "this should be handled by higher-level code");
// Per JVMS 5.4.4 we first resolve and validate the current class, then
// the target class k.
InstanceKlass* cur_host = nest_host(CHECK_false);
if (cur_host == nullptr) {
return false;
}
Klass* k_nest_host = k->nest_host(CHECK_false);
if (k_nest_host == nullptr) {
return false;
}
bool access = (cur_host == k_nest_host);
ResourceMark rm(THREAD);
log_trace(class, nestmates)("Class %s does %shave nestmate access to %s",
this->external_name(),
access ? "" : "NOT ",
k->external_name());
return access;
}
const char* InstanceKlass::nest_host_error() {
if (_nest_host_index == 0) {
return nullptr;
} else {
constantPoolHandle cph(Thread::current(), constants());
return SystemDictionary::find_nest_host_error(cph, (int)_nest_host_index);
}
}
InstanceKlass* InstanceKlass::allocate_instance_klass(const ClassFileParser& parser, TRAPS) {
const int size = InstanceKlass::size(parser.vtable_size(),
parser.itable_size(),
nonstatic_oop_map_size(parser.total_oop_map_count()),
parser.is_interface());
const Symbol* const class_name = parser.class_name();
assert(class_name != nullptr, "invariant");
ClassLoaderData* loader_data = parser.loader_data();
assert(loader_data != nullptr, "invariant");
InstanceKlass* ik;
// Allocation
if (parser.is_instance_ref_klass()) {
// java.lang.ref.Reference
ik = new (loader_data, size, THREAD) InstanceRefKlass(parser);
} else if (class_name == vmSymbols::java_lang_Class()) {
// mirror - java.lang.Class
ik = new (loader_data, size, THREAD) InstanceMirrorKlass(parser);
} else if (is_stack_chunk_class(class_name, loader_data)) {
// stack chunk
ik = new (loader_data, size, THREAD) InstanceStackChunkKlass(parser);
} else if (is_class_loader(class_name, parser)) {
// class loader - java.lang.ClassLoader
ik = new (loader_data, size, THREAD) InstanceClassLoaderKlass(parser);
} else {
// normal
ik = new (loader_data, size, THREAD) InstanceKlass(parser);
}
// Check for pending exception before adding to the loader data and incrementing
// class count. Can get OOM here.
if (HAS_PENDING_EXCEPTION) {
return nullptr;
}
return ik;
}
// copy method ordering from resource area to Metaspace
void InstanceKlass::copy_method_ordering(const intArray* m, TRAPS) {
if (m != nullptr) {
// allocate a new array and copy contents (memcpy?)
_method_ordering = MetadataFactory::new_array<int>(class_loader_data(), m->length(), CHECK);
for (int i = 0; i < m->length(); i++) {
_method_ordering->at_put(i, m->at(i));
}
} else {
_method_ordering = Universe::the_empty_int_array();
}
}
// create a new array of vtable_indices for default methods
Array<int>* InstanceKlass::create_new_default_vtable_indices(int len, TRAPS) {
Array<int>* vtable_indices = MetadataFactory::new_array<int>(class_loader_data(), len, CHECK_NULL);
assert(default_vtable_indices() == nullptr, "only create once");
set_default_vtable_indices(vtable_indices);
return vtable_indices;
}
static Monitor* create_init_monitor(const char* name) {
return new Monitor(Mutex::safepoint, name);
}
InstanceKlass::InstanceKlass(const ClassFileParser& parser, KlassKind kind, ReferenceType reference_type) :
Klass(kind),
_nest_members(nullptr),
_nest_host(nullptr),
_permitted_subclasses(nullptr),
_record_components(nullptr),
_static_field_size(parser.static_field_size()),
_nonstatic_oop_map_size(nonstatic_oop_map_size(parser.total_oop_map_count())),
_itable_len(parser.itable_size()),
_nest_host_index(0),
_init_state(allocated),
_reference_type(reference_type),
_init_monitor(create_init_monitor("InstanceKlassInitMonitor_lock")),
_init_thread(nullptr)
{
set_vtable_length(parser.vtable_size());
set_access_flags(parser.access_flags());
if (parser.is_hidden()) set_is_hidden();
set_layout_helper(Klass::instance_layout_helper(parser.layout_size(),
false));
assert(nullptr == _methods, "underlying memory not zeroed?");
assert(is_instance_klass(), "is layout incorrect?");
assert(size_helper() == parser.layout_size(), "incorrect size_helper?");
}
void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
Array<Method*>* methods) {
if (methods != nullptr && methods != Universe::the_empty_method_array() &&
!methods->is_shared()) {
for (int i = 0; i < methods->length(); i++) {
Method* method = methods->at(i);
if (method == nullptr) continue; // maybe null if error processing
// Only want to delete methods that are not executing for RedefineClasses.
// The previous version will point to them so they're not totally dangling
assert (!method->on_stack(), "shouldn't be called with methods on stack");
MetadataFactory::free_metadata(loader_data, method);
}
MetadataFactory::free_array<Method*>(loader_data, methods);
}
}
void InstanceKlass::deallocate_interfaces(ClassLoaderData* loader_data,
const Klass* super_klass,
Array<InstanceKlass*>* local_interfaces,
Array<InstanceKlass*>* transitive_interfaces) {
// Only deallocate transitive interfaces if not empty, same as super class
// or same as local interfaces. See code in parseClassFile.
Array<InstanceKlass*>* ti = transitive_interfaces;
if (ti != Universe::the_empty_instance_klass_array() && ti != local_interfaces) {
// check that the interfaces don't come from super class
Array<InstanceKlass*>* sti = (super_klass == nullptr) ? nullptr :
InstanceKlass::cast(super_klass)->transitive_interfaces();
if (ti != sti && ti != nullptr && !ti->is_shared()) {
MetadataFactory::free_array<InstanceKlass*>(loader_data, ti);
}
}
// local interfaces can be empty
if (local_interfaces != Universe::the_empty_instance_klass_array() &&
local_interfaces != nullptr && !local_interfaces->is_shared()) {
MetadataFactory::free_array<InstanceKlass*>(loader_data, local_interfaces);
}
}
void InstanceKlass::deallocate_record_components(ClassLoaderData* loader_data,
Array<RecordComponent*>* record_components) {
if (record_components != nullptr && !record_components->is_shared()) {
for (int i = 0; i < record_components->length(); i++) {
RecordComponent* record_component = record_components->at(i);
MetadataFactory::free_metadata(loader_data, record_component);
}
MetadataFactory::free_array<RecordComponent*>(loader_data, record_components);
}
}
// This function deallocates the metadata and C heap pointers that the
// InstanceKlass points to.
void InstanceKlass::deallocate_contents(ClassLoaderData* loader_data) {
// Orphan the mirror first, CMS thinks it's still live.
if (java_mirror() != nullptr) {
java_lang_Class::set_klass(java_mirror(), nullptr);
}
// Also remove mirror from handles
loader_data->remove_handle(_java_mirror);
// Need to take this class off the class loader data list.
loader_data->remove_class(this);
// The array_klass for this class is created later, after error handling.
// For class redefinition, we keep the original class so this scratch class
// doesn't have an array class. Either way, assert that there is nothing
// to deallocate.
assert(array_klasses() == nullptr, "array classes shouldn't be created for this class yet");
// Release C heap allocated data that this points to, which includes
// reference counting symbol names.
// Can't release the constant pool or MethodData C heap data here because the constant
// pool can be deallocated separately from the InstanceKlass for default methods and
// redefine classes. MethodData can also be released separately.
release_C_heap_structures(/* release_sub_metadata */ false);
deallocate_methods(loader_data, methods());
set_methods(nullptr);
deallocate_record_components(loader_data, record_components());
set_record_components(nullptr);
if (method_ordering() != nullptr &&
method_ordering() != Universe::the_empty_int_array() &&
!method_ordering()->is_shared()) {
MetadataFactory::free_array<int>(loader_data, method_ordering());
}
set_method_ordering(nullptr);
// default methods can be empty
if (default_methods() != nullptr &&
default_methods() != Universe::the_empty_method_array() &&
!default_methods()->is_shared()) {
MetadataFactory::free_array<Method*>(loader_data, default_methods());
}
// Do NOT deallocate the default methods, they are owned by superinterfaces.
set_default_methods(nullptr);
// default methods vtable indices can be empty
if (default_vtable_indices() != nullptr &&
!default_vtable_indices()->is_shared()) {
MetadataFactory::free_array<int>(loader_data, default_vtable_indices());
}
set_default_vtable_indices(nullptr);
// This array is in Klass, but remove it with the InstanceKlass since
// this place would be the only caller and it can share memory with transitive
// interfaces.
if (secondary_supers() != nullptr &&
secondary_supers() != Universe::the_empty_klass_array() &&
// see comments in compute_secondary_supers about the following cast
(address)(secondary_supers()) != (address)(transitive_interfaces()) &&
!secondary_supers()->is_shared()) {
MetadataFactory::free_array<Klass*>(loader_data, secondary_supers());
}
set_secondary_supers(nullptr);
deallocate_interfaces(loader_data, super(), local_interfaces(), transitive_interfaces());
set_transitive_interfaces(nullptr);
set_local_interfaces(nullptr);
if (fieldinfo_stream() != nullptr && !fieldinfo_stream()->is_shared()) {
MetadataFactory::free_array<u1>(loader_data, fieldinfo_stream());
}
set_fieldinfo_stream(nullptr);
if (fields_status() != nullptr && !fields_status()->is_shared()) {
MetadataFactory::free_array<FieldStatus>(loader_data, fields_status());
}
set_fields_status(nullptr);
// If a method from a redefined class is using this constant pool, don't
// delete it, yet. The new class's previous version will point to this.
if (constants() != nullptr) {
assert (!constants()->on_stack(), "shouldn't be called if anything is onstack");
if (!constants()->is_shared()) {
MetadataFactory::free_metadata(loader_data, constants());
}
// Delete any cached resolution errors for the constant pool
SystemDictionary::delete_resolution_error(constants());
set_constants(nullptr);
}
if (inner_classes() != nullptr &&
inner_classes() != Universe::the_empty_short_array() &&
!inner_classes()->is_shared()) {
MetadataFactory::free_array<jushort>(loader_data, inner_classes());
}
set_inner_classes(nullptr);
if (nest_members() != nullptr &&
nest_members() != Universe::the_empty_short_array() &&
!nest_members()->is_shared()) {
MetadataFactory::free_array<jushort>(loader_data, nest_members());
}
set_nest_members(nullptr);
if (permitted_subclasses() != nullptr &&
permitted_subclasses() != Universe::the_empty_short_array() &&
!permitted_subclasses()->is_shared()) {
MetadataFactory::free_array<jushort>(loader_data, permitted_subclasses());
}
set_permitted_subclasses(nullptr);
// We should deallocate the Annotations instance if it's not in shared spaces.
if (annotations() != nullptr && !annotations()->is_shared()) {
MetadataFactory::free_metadata(loader_data, annotations());
}
set_annotations(nullptr);
SystemDictionaryShared::handle_class_unloading(this);
#if INCLUDE_CDS_JAVA_HEAP
if (DumpSharedSpaces) {
HeapShared::remove_scratch_objects(this);
}
#endif
}
bool InstanceKlass::is_record() const {
return _record_components != nullptr &&
is_final() &&
java_super() == vmClasses::Record_klass();
}
bool InstanceKlass::is_sealed() const {
return _permitted_subclasses != nullptr &&
_permitted_subclasses != Universe::the_empty_short_array();
}
bool InstanceKlass::should_be_initialized() const {
return !is_initialized();
}
klassItable InstanceKlass::itable() const {
return klassItable(const_cast<InstanceKlass*>(this));
}
// JVMTI spec thinks there are signers and protection domain in the
// instanceKlass. These accessors pretend these fields are there.
// The hprof specification also thinks these fields are in InstanceKlass.
oop InstanceKlass::protection_domain() const {
// return the protection_domain from the mirror
return java_lang_Class::protection_domain(java_mirror());
}
objArrayOop InstanceKlass::signers() const {
// return the signers from the mirror
return java_lang_Class::signers(java_mirror());
}
// See "The Virtual Machine Specification" section 2.16.5 for a detailed explanation of the class initialization
// process. The step comments refers to the procedure described in that section.
// Note: implementation moved to static method to expose the this pointer.
void InstanceKlass::initialize(TRAPS) {
if (this->should_be_initialized()) {
initialize_impl(CHECK);
// Note: at this point the class may be initialized
// OR it may be in the state of being initialized
// in case of recursive initialization!
} else {
assert(is_initialized(), "sanity check");
}
}
bool InstanceKlass::verify_code(TRAPS) {
// 1) Verify the bytecodes
return Verifier::verify(this, should_verify_class(), THREAD);
}
void InstanceKlass::link_class(TRAPS) {
assert(is_loaded(), "must be loaded");
if (!is_linked()) {
link_class_impl(CHECK);
}
}
void InstanceKlass::check_link_state_and_wait(JavaThread* current) {
MonitorLocker ml(current, _init_monitor);
bool debug_logging_enabled = log_is_enabled(Debug, class, init);
// Another thread is linking this class, wait.
while (is_being_linked() && !is_init_thread(current)) {
if (debug_logging_enabled) {
ResourceMark rm(current);
log_debug(class, init)("Thread \"%s\" waiting for linking of %s by thread \"%s\"",
current->name(), external_name(), init_thread_name());
}
ml.wait();
}
// This thread is recursively linking this class, continue
if (is_being_linked() && is_init_thread(current)) {
if (debug_logging_enabled) {
ResourceMark rm(current);
log_debug(class, init)("Thread \"%s\" recursively linking %s",
current->name(), external_name());
}
return;
}
// If this class wasn't linked already, set state to being_linked
if (!is_linked()) {
if (debug_logging_enabled) {
ResourceMark rm(current);
log_debug(class, init)("Thread \"%s\" linking %s",
current->name(), external_name());
}
set_init_state(being_linked);
set_init_thread(current);
} else {
if (debug_logging_enabled) {
ResourceMark rm(current);
log_debug(class, init)("Thread \"%s\" found %s already linked",
current->name(), external_name());
}
}
}
// Called to verify that a class can link during initialization, without
// throwing a VerifyError.
bool InstanceKlass::link_class_or_fail(TRAPS) {
assert(is_loaded(), "must be loaded");
if (!is_linked()) {
link_class_impl(CHECK_false);
}
return is_linked();
}
bool InstanceKlass::link_class_impl(TRAPS) {
if (DumpSharedSpaces && SystemDictionaryShared::has_class_failed_verification(this)) {
// This is for CDS dumping phase only -- we use the in_error_state to indicate that
// the class has failed verification. Throwing the NoClassDefFoundError here is just
// a convenient way to stop repeat attempts to verify the same (bad) class.
//
// Note that the NoClassDefFoundError is not part of the JLS, and should not be thrown
// if we are executing Java code. This is not a problem for CDS dumping phase since
// it doesn't execute any Java code.
ResourceMark rm(THREAD);
Exceptions::fthrow(THREAD_AND_LOCATION,
vmSymbols::java_lang_NoClassDefFoundError(),
"Class %s, or one of its supertypes, failed class initialization",
external_name());
return false;
}
// return if already verified
if (is_linked()) {
return true;
}
// Timing
// timer handles recursion
JavaThread* jt = THREAD;
// link super class before linking this class
Klass* super_klass = super();
if (super_klass != nullptr) {
if (super_klass->is_interface()) { // check if super class is an interface
ResourceMark rm(THREAD);
Exceptions::fthrow(
THREAD_AND_LOCATION,
vmSymbols::java_lang_IncompatibleClassChangeError(),
"class %s has interface %s as super class",
external_name(),
super_klass->external_name()
);
return false;
}
InstanceKlass* ik_super = InstanceKlass::cast(super_klass);
ik_super->link_class_impl(CHECK_false);
}
// link all interfaces implemented by this class before linking this class
Array<InstanceKlass*>* interfaces = local_interfaces();
int num_interfaces = interfaces->length();
for (int index = 0; index < num_interfaces; index++) {
InstanceKlass* interk = interfaces->at(index);
interk->link_class_impl(CHECK_false);
}
// in case the class is linked in the process of linking its superclasses
if (is_linked()) {
return true;
}
// trace only the link time for this klass that includes
// the verification time
PerfClassTraceTime vmtimer(ClassLoader::perf_class_link_time(),
ClassLoader::perf_class_link_selftime(),
ClassLoader::perf_classes_linked(),
jt->get_thread_stat()->perf_recursion_counts_addr(),
jt->get_thread_stat()->perf_timers_addr(),
PerfClassTraceTime::CLASS_LINK);
// verification & rewriting
{
LockLinkState init_lock(this, jt);
// rewritten will have been set if loader constraint error found
// on an earlier link attempt
// don't verify or rewrite if already rewritten
//
if (!is_linked()) {
if (!is_rewritten()) {
if (is_shared()) {
assert(!verified_at_dump_time(), "must be");
}
{
bool verify_ok = verify_code(THREAD);
if (!verify_ok) {
return false;
}
}
// Just in case a side-effect of verify linked this class already
// (which can sometimes happen since the verifier loads classes
// using custom class loaders, which are free to initialize things)
if (is_linked()) {
return true;
}
// also sets rewritten
rewrite_class(CHECK_false);
} else if (is_shared()) {
SystemDictionaryShared::check_verification_constraints(this, CHECK_false);
}
// relocate jsrs and link methods after they are all rewritten
link_methods(CHECK_false);
// Initialize the vtable and interface table after
// methods have been rewritten since rewrite may
// fabricate new Method*s.
// also does loader constraint checking
//
// initialize_vtable and initialize_itable need to be rerun
// for a shared class if
// 1) the class is loaded by custom class loader or
// 2) the class is loaded by built-in class loader but failed to add archived loader constraints or
// 3) the class was not verified during dump time
bool need_init_table = true;
if (is_shared() && verified_at_dump_time() &&
SystemDictionaryShared::check_linking_constraints(THREAD, this)) {
need_init_table = false;
}
if (need_init_table) {
vtable().initialize_vtable_and_check_constraints(CHECK_false);
itable().initialize_itable_and_check_constraints(CHECK_false);
}
#ifdef ASSERT
vtable().verify(tty, true);
// In case itable verification is ever added.
// itable().verify(tty, true);
#endif
set_initialization_state_and_notify(linked, THREAD);
if (JvmtiExport::should_post_class_prepare()) {
JvmtiExport::post_class_prepare(THREAD, this);
}
}
}
return true;
}
// Rewrite the byte codes of all of the methods of a class.
// The rewriter must be called exactly once. Rewriting must happen after
// verification but before the first method of the class is executed.
void InstanceKlass::rewrite_class(TRAPS) {
assert(is_loaded(), "must be loaded");
if (is_rewritten()) {
assert(is_shared(), "rewriting an unshared class?");
return;
}
Rewriter::rewrite(this, CHECK);
set_rewritten();
}
// Now relocate and link method entry points after class is rewritten.
// This is outside is_rewritten flag. In case of an exception, it can be
// executed more than once.
void InstanceKlass::link_methods(TRAPS) {
int len = methods()->length();
for (int i = len-1; i >= 0; i--) {
methodHandle m(THREAD, methods()->at(i));
// Set up method entry points for compiler and interpreter .
m->link_method(m, CHECK);
}
}
// Eagerly initialize superinterfaces that declare default methods (concrete instance: any access)
void InstanceKlass::initialize_super_interfaces(TRAPS) {
assert (has_nonstatic_concrete_methods(), "caller should have checked this");
for (int i = 0; i < local_interfaces()->length(); ++i) {
InstanceKlass* ik = local_interfaces()->at(i);
// Initialization is depth first search ie. we start with top of the inheritance tree
// has_nonstatic_concrete_methods drives searching superinterfaces since it
// means has_nonstatic_concrete_methods in its superinterface hierarchy
if (ik->has_nonstatic_concrete_methods()) {
ik->initialize_super_interfaces(CHECK);
}
// Only initialize() interfaces that "declare" concrete methods.
if (ik->should_be_initialized() && ik->declares_nonstatic_concrete_methods()) {
ik->initialize(CHECK);
}
}
}
using InitializationErrorTable = ResourceHashtable<const InstanceKlass*, OopHandle, 107, AnyObj::C_HEAP, mtClass>;
static InitializationErrorTable* _initialization_error_table;
void InstanceKlass::add_initialization_error(JavaThread* current, Handle exception) {
// Create the same exception with a message indicating the thread name,
// and the StackTraceElements.
// If the initialization error is OOM, this might not work, but if GC kicks in
// this would be still be helpful.
JavaThread* THREAD = current;
Handle init_error = java_lang_Throwable::create_initialization_error(current, exception);
ResourceMark rm(THREAD);
if (init_error.is_null()) {
log_trace(class, init)("Initialization error is null for class %s", external_name());
return;
}
MutexLocker ml(THREAD, ClassInitError_lock);
OopHandle elem = OopHandle(Universe::vm_global(), init_error());
bool created;
if (_initialization_error_table == nullptr) {
_initialization_error_table = new (mtClass) InitializationErrorTable();
}
_initialization_error_table->put_if_absent(this, elem, &created);
assert(created, "Initialization is single threaded");
log_trace(class, init)("Initialization error added for class %s", external_name());
}
oop InstanceKlass::get_initialization_error(JavaThread* current) {
MutexLocker ml(current, ClassInitError_lock);
if (_initialization_error_table == nullptr) {
return nullptr;
}
OopHandle* h = _initialization_error_table->get(this);
return (h != nullptr) ? h->resolve() : nullptr;
}
// Need to remove entries for unloaded classes.
void InstanceKlass::clean_initialization_error_table() {
struct InitErrorTableCleaner {
bool do_entry(const InstanceKlass* ik, OopHandle h) {
if (!ik->is_loader_alive()) {
h.release(Universe::vm_global());
return true;
} else {
return false;
}
}
};
assert_locked_or_safepoint(ClassInitError_lock);
InitErrorTableCleaner cleaner;
if (_initialization_error_table != nullptr) {
_initialization_error_table->unlink(&cleaner);
}
}
void InstanceKlass::initialize_impl(TRAPS) {
HandleMark hm(THREAD);
// Make sure klass is linked (verified) before initialization
// A class could already be verified, since it has been reflected upon.
link_class(CHECK);
DTRACE_CLASSINIT_PROBE(required, -1);
bool wait = false;
bool throw_error = false;
JavaThread* jt = THREAD;
bool debug_logging_enabled = log_is_enabled(Debug, class, init);
// refer to the JVM book page 47 for description of steps
// Step 1
{
MonitorLocker ml(jt, _init_monitor);
// Step 2
while (is_being_initialized() && !is_init_thread(jt)) {
if (debug_logging_enabled) {
ResourceMark rm(jt);
log_debug(class, init)("Thread \"%s\" waiting for initialization of %s by thread \"%s\"",
jt->name(), external_name(), init_thread_name());
}
wait = true;
jt->set_class_to_be_initialized(this);
ml.wait();
jt->set_class_to_be_initialized(nullptr);
}
// Step 3
if (is_being_initialized() && is_init_thread(jt)) {
if (debug_logging_enabled) {
ResourceMark rm(jt);
log_debug(class, init)("Thread \"%s\" recursively initializing %s",
jt->name(), external_name());
}
DTRACE_CLASSINIT_PROBE_WAIT(recursive, -1, wait);
return;
}
// Step 4
if (is_initialized()) {
if (debug_logging_enabled) {
ResourceMark rm(jt);
log_debug(class, init)("Thread \"%s\" found %s already initialized",
jt->name(), external_name());
}
DTRACE_CLASSINIT_PROBE_WAIT(concurrent, -1, wait);
return;
}
// Step 5
if (is_in_error_state()) {
if (debug_logging_enabled) {
ResourceMark rm(jt);
log_debug(class, init)("Thread \"%s\" found %s is in error state",
jt->name(), external_name());
}
throw_error = true;
} else {
// Step 6
set_init_state(being_initialized);
set_init_thread(jt);
if (debug_logging_enabled) {
ResourceMark rm(jt);
log_debug(class, init)("Thread \"%s\" is initializing %s",
jt->name(), external_name());
}
}
}
// Throw error outside lock
if (throw_error) {
DTRACE_CLASSINIT_PROBE_WAIT(erroneous, -1, wait);
ResourceMark rm(THREAD);
Handle cause(THREAD, get_initialization_error(THREAD));
stringStream ss;
ss.print("Could not initialize class %s", external_name());
if (cause.is_null()) {
THROW_MSG(vmSymbols::java_lang_NoClassDefFoundError(), ss.as_string());
} else {
THROW_MSG_CAUSE(vmSymbols::java_lang_NoClassDefFoundError(),
ss.as_string(), cause);
}
}
// Step 7
// Next, if C is a class rather than an interface, initialize it's super class and super
// interfaces.
if (!is_interface()) {
Klass* super_klass = super();
if (super_klass != nullptr && super_klass->should_be_initialized()) {
super_klass->initialize(THREAD);
}
// If C implements any interface that declares a non-static, concrete method,
// the initialization of C triggers initialization of its super interfaces.
// Only need to recurse if has_nonstatic_concrete_methods which includes declaring and
// having a superinterface that declares, non-static, concrete methods
if (!HAS_PENDING_EXCEPTION && has_nonstatic_concrete_methods()) {
initialize_super_interfaces(THREAD);
}
// If any exceptions, complete abruptly, throwing the same exception as above.
if (HAS_PENDING_EXCEPTION) {
Handle e(THREAD, PENDING_EXCEPTION);
CLEAR_PENDING_EXCEPTION;
{
EXCEPTION_MARK;
add_initialization_error(THREAD, e);
// Locks object, set state, and notify all waiting threads
set_initialization_state_and_notify(initialization_error, THREAD);
CLEAR_PENDING_EXCEPTION;
}
DTRACE_CLASSINIT_PROBE_WAIT(super__failed, -1, wait);
THROW_OOP(e());
}
}
// Step 8
{
DTRACE_CLASSINIT_PROBE_WAIT(clinit, -1, wait);
if (class_initializer() != nullptr) {
// Timer includes any side effects of class initialization (resolution,
// etc), but not recursive entry into call_class_initializer().
PerfClassTraceTime timer(ClassLoader::perf_class_init_time(),
ClassLoader::perf_class_init_selftime(),
ClassLoader::perf_classes_inited(),
jt->get_thread_stat()->perf_recursion_counts_addr(),
jt->get_thread_stat()->perf_timers_addr(),
PerfClassTraceTime::CLASS_CLINIT);
call_class_initializer(THREAD);
} else {
// The elapsed time is so small it's not worth counting.
if (UsePerfData) {
ClassLoader::perf_classes_inited()->inc();
}
call_class_initializer(THREAD);
}
}
// Step 9
if (!HAS_PENDING_EXCEPTION) {
set_initialization_state_and_notify(fully_initialized, THREAD);
debug_only(vtable().verify(tty, true);)
}
else {
// Step 10 and 11
Handle e(THREAD, PENDING_EXCEPTION);
CLEAR_PENDING_EXCEPTION;
// JVMTI has already reported the pending exception
// JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
JvmtiExport::clear_detected_exception(jt);
{
EXCEPTION_MARK;
add_initialization_error(THREAD, e);
set_initialization_state_and_notify(initialization_error, THREAD);
CLEAR_PENDING_EXCEPTION; // ignore any exception thrown, class initialization error is thrown below
// JVMTI has already reported the pending exception
// JVMTI internal flag reset is needed in order to report ExceptionInInitializerError
JvmtiExport::clear_detected_exception(jt);
}
DTRACE_CLASSINIT_PROBE_WAIT(error, -1, wait);
if (e->is_a(vmClasses::Error_klass())) {
THROW_OOP(e());
} else {
JavaCallArguments args(e);
THROW_ARG(vmSymbols::java_lang_ExceptionInInitializerError(),
vmSymbols::throwable_void_signature(),
&args);
}
}
DTRACE_CLASSINIT_PROBE_WAIT(end, -1, wait);
}
void InstanceKlass::set_initialization_state_and_notify(ClassState state, JavaThread* current) {
MonitorLocker ml(current, _init_monitor);
if (state == linked && UseVtableBasedCHA && Universe::is_fully_initialized()) {
DeoptimizationScope deopt_scope;
{
// Now mark all code that assumes the class is not linked.
// Set state under the Compile_lock also.
MutexLocker ml(current, Compile_lock);
set_init_thread(nullptr); // reset _init_thread before changing _init_state
set_init_state(state);
CodeCache::mark_dependents_on(&deopt_scope, this);
}
// Perform the deopt handshake outside Compile_lock.
deopt_scope.deoptimize_marked();
} else {
set_init_thread(nullptr); // reset _init_thread before changing _init_state
set_init_state(state);
}
ml.notify_all();
}
// Update hierarchy. This is done before the new klass has been added to the SystemDictionary. The Compile_lock
// is grabbed, to ensure that the compiler is not using the class hierarchy.
void InstanceKlass::add_to_hierarchy(JavaThread* current) {
assert(!SafepointSynchronize::is_at_safepoint(), "must NOT be at safepoint");
// In case we are not using CHA based vtables we need to make sure the loaded
// deopt is completed before anyone links this class.
// Linking is done with _init_monitor held, by loading and deopting with it
// held we make sure the deopt is completed before linking.
if (!UseVtableBasedCHA) {
init_monitor()->lock();
}
DeoptimizationScope deopt_scope;
{
MutexLocker ml(current, Compile_lock);
set_init_state(InstanceKlass::loaded);
// make sure init_state store is already done.
// The compiler reads the hierarchy outside of the Compile_lock.
// Access ordering is used to add to hierarchy.
// Link into hierarchy.
append_to_sibling_list(); // add to superklass/sibling list
process_interfaces(); // handle all "implements" declarations
// Now mark all code that depended on old class hierarchy.
// Note: must be done *after* linking k into the hierarchy (was bug 12/9/97)
if (Universe::is_fully_initialized()) {
CodeCache::mark_dependents_on(&deopt_scope, this);
}
}
// Perform the deopt handshake outside Compile_lock.
deopt_scope.deoptimize_marked();
if (!UseVtableBasedCHA) {
init_monitor()->unlock();
}
}
InstanceKlass* InstanceKlass::implementor() const {
InstanceKlass* volatile* ik = adr_implementor();
if (ik == nullptr) {
return nullptr;
} else {
// This load races with inserts, and therefore needs acquire.
InstanceKlass* ikls = Atomic::load_acquire(ik);
if (ikls != nullptr && !ikls->is_loader_alive()) {
return nullptr; // don't return unloaded class
} else {
return ikls;
}
}
}
void InstanceKlass::set_implementor(InstanceKlass* ik) {
assert_locked_or_safepoint(Compile_lock);
assert(is_interface(), "not interface");
InstanceKlass* volatile* addr = adr_implementor();
assert(addr != nullptr, "null addr");
if (addr != nullptr) {
Atomic::release_store(addr, ik);
}
}
int InstanceKlass::nof_implementors() const {
InstanceKlass* ik = implementor();
if (ik == nullptr) {
return 0;
} else if (ik != this) {
return 1;
} else {
return 2;
}
}
// The embedded _implementor field can only record one implementor.
// When there are more than one implementors, the _implementor field
// is set to the interface Klass* itself. Following are the possible
// values for the _implementor field:
// null - no implementor
// implementor Klass* - one implementor
// self - more than one implementor
//
// The _implementor field only exists for interfaces.
void InstanceKlass::add_implementor(InstanceKlass* ik) {
if (Universe::is_fully_initialized()) {
assert_lock_strong(Compile_lock);
}
assert(is_interface(), "not interface");
// Filter out my subinterfaces.
// (Note: Interfaces are never on the subklass list.)
if (ik->is_interface()) return;
// Filter out subclasses whose supers already implement me.
// (Note: CHA must walk subclasses of direct implementors
// in order to locate indirect implementors.)
InstanceKlass* super_ik = ik->java_super();
if (super_ik != nullptr && super_ik->implements_interface(this))
// We only need to check one immediate superclass, since the
// implements_interface query looks at transitive_interfaces.
// Any supers of the super have the same (or fewer) transitive_interfaces.
return;
InstanceKlass* iklass = implementor();
if (iklass == nullptr) {
set_implementor(ik);
} else if (iklass != this && iklass != ik) {
// There is already an implementor. Use itself as an indicator of
// more than one implementors.
set_implementor(this);
}
// The implementor also implements the transitive_interfaces
for (int index = 0; index < local_interfaces()->length(); index++) {
local_interfaces()->at(index)->add_implementor(ik);
}
}
void InstanceKlass::init_implementor() {
if (is_interface()) {
set_implementor(nullptr);
}
}
void InstanceKlass::process_interfaces() {
// link this class into the implementors list of every interface it implements
for (int i = local_interfaces()->length() - 1; i >= 0; i--) {
assert(local_interfaces()->at(i)->is_klass(), "must be a klass");
InstanceKlass* interf = local_interfaces()->at(i);
assert(interf->is_interface(), "expected interface");
interf->add_implementor(this);
}
}
bool InstanceKlass::can_be_primary_super_slow() const {
if (is_interface())
return false;
else
return Klass::can_be_primary_super_slow();
}
GrowableArray<Klass*>* InstanceKlass::compute_secondary_supers(int num_extra_slots,
Array<InstanceKlass*>* transitive_interfaces) {
// The secondaries are the implemented interfaces.
Array<InstanceKlass*>* interfaces = transitive_interfaces;
int num_secondaries = num_extra_slots + interfaces->length();
if (num_secondaries == 0) {
// Must share this for correct bootstrapping!
set_secondary_supers(Universe::the_empty_klass_array());
return nullptr;
} else if (num_extra_slots == 0) {
// The secondary super list is exactly the same as the transitive interfaces, so
// let's use it instead of making a copy.
// Redefine classes has to be careful not to delete this!
// We need the cast because Array<Klass*> is NOT a supertype of Array<InstanceKlass*>,
// (but it's safe to do here because we won't write into _secondary_supers from this point on).
set_secondary_supers((Array<Klass*>*)(address)interfaces);
return nullptr;
} else {
// Copy transitive interfaces to a temporary growable array to be constructed
// into the secondary super list with extra slots.
GrowableArray<Klass*>* secondaries = new GrowableArray<Klass*>(interfaces->length());
for (int i = 0; i < interfaces->length(); i++) {
secondaries->push(interfaces->at(i));
}
return secondaries;
}
}
bool InstanceKlass::implements_interface(Klass* k) const {
if (this == k) return true;
assert(k->is_interface(), "should be an interface class");
for (int i = 0; i < transitive_interfaces()->length(); i++) {
if (transitive_interfaces()->at(i) == k) {
return true;
}
}
return false;
}
bool InstanceKlass::is_same_or_direct_interface(Klass *k) const {
// Verify direct super interface
if (this == k) return true;
assert(k->is_interface(), "should be an interface class");
for (int i = 0; i < local_interfaces()->length(); i++) {
if (local_interfaces()->at(i) == k) {
return true;
}
}
return false;
}
objArrayOop InstanceKlass::allocate_objArray(int n, int length, TRAPS) {
check_array_allocation_length(length, arrayOopDesc::max_array_length(T_OBJECT), CHECK_NULL);
size_t size = objArrayOopDesc::object_size(length);
Klass* ak = array_klass(n, CHECK_NULL);
objArrayOop o = (objArrayOop)Universe::heap()->array_allocate(ak, size, length,
/* do_zero */ true, CHECK_NULL);
return o;
}
instanceOop InstanceKlass::register_finalizer(instanceOop i, TRAPS) {
if (TraceFinalizerRegistration) {
tty->print("Registered ");
i->print_value_on(tty);
tty->print_cr(" (" PTR_FORMAT ") as finalizable", p2i(i));
}
instanceHandle h_i(THREAD, i);
// Pass the handle as argument, JavaCalls::call expects oop as jobjects
JavaValue result(T_VOID);
JavaCallArguments args(h_i);
methodHandle mh(THREAD, Universe::finalizer_register_method());
JavaCalls::call(&result, mh, &args, CHECK_NULL);
MANAGEMENT_ONLY(FinalizerService::on_register(h_i(), THREAD);)
return h_i();
}
instanceOop InstanceKlass::allocate_instance(TRAPS) {
bool has_finalizer_flag = has_finalizer(); // Query before possible GC
size_t size = size_helper(); // Query before forming handle.
instanceOop i;
i = (instanceOop)Universe::heap()->obj_allocate(this, size, CHECK_NULL);
if (has_finalizer_flag && !RegisterFinalizersAtInit) {
i = register_finalizer(i, CHECK_NULL);
}
return i;
}
instanceOop InstanceKlass::allocate_instance(oop java_class, TRAPS) {
Klass* k = java_lang_Class::as_Klass(java_class);
if (k == nullptr) {
ResourceMark rm(THREAD);
THROW_(vmSymbols::java_lang_InstantiationException(), nullptr);
}
InstanceKlass* ik = cast(k);
ik->check_valid_for_instantiation(false, CHECK_NULL);
ik->initialize(CHECK_NULL);
return ik->allocate_instance(THREAD);
}
instanceHandle InstanceKlass::allocate_instance_handle(TRAPS) {
return instanceHandle(THREAD, allocate_instance(THREAD));
}
void InstanceKlass::check_valid_for_instantiation(bool throwError, TRAPS) {
if (is_interface() || is_abstract()) {
ResourceMark rm(THREAD);
THROW_MSG(throwError ? vmSymbols::java_lang_InstantiationError()
: vmSymbols::java_lang_InstantiationException(), external_name());
}
if (this == vmClasses::Class_klass()) {
ResourceMark rm(THREAD);
THROW_MSG(throwError ? vmSymbols::java_lang_IllegalAccessError()
: vmSymbols::java_lang_IllegalAccessException(), external_name());
}
}
Klass* InstanceKlass::array_klass(int n, TRAPS) {
// Need load-acquire for lock-free read
if (array_klasses_acquire() == nullptr) {
ResourceMark rm(THREAD);
JavaThread *jt = THREAD;
{
// Atomic creation of array_klasses
MutexLocker ma(THREAD, MultiArray_lock);
// Check if update has already taken place
if (array_klasses() == nullptr) {
ObjArrayKlass* k = ObjArrayKlass::allocate_objArray_klass(class_loader_data(), 1, this, CHECK_NULL);
// use 'release' to pair with lock-free load
release_set_array_klasses(k);
}
}
}
// array_klasses() will always be set at this point
ObjArrayKlass* oak = array_klasses();
return oak->array_klass(n, THREAD);
}
Klass* InstanceKlass::array_klass_or_null(int n) {
// Need load-acquire for lock-free read
ObjArrayKlass* oak = array_klasses_acquire();
if (oak == nullptr) {
return nullptr;
} else {
return oak->array_klass_or_null(n);
}
}
Klass* InstanceKlass::array_klass(TRAPS) {
return array_klass(1, THREAD);
}
Klass* InstanceKlass::array_klass_or_null() {
return array_klass_or_null(1);
}
static int call_class_initializer_counter = 0; // for debugging
Method* InstanceKlass::class_initializer() const {
Method* clinit = find_method(
vmSymbols::class_initializer_name(), vmSymbols::void_method_signature());
if (clinit != nullptr && clinit->has_valid_initializer_flags()) {
return clinit;
}
return nullptr;
}
void InstanceKlass::call_class_initializer(TRAPS) {
if (ReplayCompiles &&
(ReplaySuppressInitializers == 1 ||
(ReplaySuppressInitializers >= 2 && class_loader() != nullptr))) {
// Hide the existence of the initializer for the purpose of replaying the compile
return;
}
#if INCLUDE_CDS
// This is needed to ensure the consistency of the archived heap objects.
if (has_archived_enum_objs()) {
assert(is_shared(), "must be");
bool initialized = HeapShared::initialize_enum_klass(this, CHECK);
if (initialized) {
return;
}
}
#endif
methodHandle h_method(THREAD, class_initializer());
assert(!is_initialized(), "we cannot initialize twice");
LogTarget(Info, class, init) lt;
if (lt.is_enabled()) {
ResourceMark rm(THREAD);
LogStream ls(lt);
ls.print("%d Initializing ", call_class_initializer_counter++);
name()->print_value_on(&ls);
ls.print_cr("%s (" PTR_FORMAT ") by thread \"%s\"",
h_method() == nullptr ? "(no method)" : "", p2i(this),
THREAD->name());
}
if (h_method() != nullptr) {
JavaCallArguments args; // No arguments
JavaValue result(T_VOID);
JavaCalls::call(&result, h_method, &args, CHECK); // Static call (no args)
}
}
void InstanceKlass::mask_for(const methodHandle& method, int bci,
InterpreterOopMap* entry_for) {
// Lazily create the _oop_map_cache at first request
// Lock-free access requires load_acquire.
OopMapCache* oop_map_cache = Atomic::load_acquire(&_oop_map_cache);
if (oop_map_cache == nullptr) {
MutexLocker x(OopMapCacheAlloc_lock);
// Check if _oop_map_cache was allocated while we were waiting for this lock
if ((oop_map_cache = _oop_map_cache) == nullptr) {
oop_map_cache = new OopMapCache();
// Ensure _oop_map_cache is stable, since it is examined without a lock
Atomic::release_store(&_oop_map_cache, oop_map_cache);
}
}
// _oop_map_cache is constant after init; lookup below does its own locking.
oop_map_cache->lookup(method, bci, entry_for);
}
bool InstanceKlass::contains_field_offset(int offset) {
fieldDescriptor fd;
return find_field_from_offset(offset, false, &fd);
}
FieldInfo InstanceKlass::field(int index) const {
for (AllFieldStream fs(this); !fs.done(); fs.next()) {
if (fs.index() == index) {
return fs.to_FieldInfo();
}
}
fatal("Field not found");
return FieldInfo();
}
bool InstanceKlass::find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
Symbol* f_name = fs.name();
Symbol* f_sig = fs.signature();
if (f_name == name && f_sig == sig) {
fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
return true;
}
}
return false;
}
Klass* InstanceKlass::find_interface_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
const int n = local_interfaces()->length();
for (int i = 0; i < n; i++) {
Klass* intf1 = local_interfaces()->at(i);
assert(intf1->is_interface(), "just checking type");
// search for field in current interface
if (InstanceKlass::cast(intf1)->find_local_field(name, sig, fd)) {
assert(fd->is_static(), "interface field must be static");
return intf1;
}
// search for field in direct superinterfaces
Klass* intf2 = InstanceKlass::cast(intf1)->find_interface_field(name, sig, fd);
if (intf2 != nullptr) return intf2;
}
// otherwise field lookup fails
return nullptr;
}
Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const {
// search order according to newest JVM spec (5.4.3.2, p.167).
// 1) search for field in current klass
if (find_local_field(name, sig, fd)) {
return const_cast<InstanceKlass*>(this);
}
// 2) search for field recursively in direct superinterfaces
{ Klass* intf = find_interface_field(name, sig, fd);
if (intf != nullptr) return intf;
}
// 3) apply field lookup recursively if superclass exists
{ Klass* supr = super();
if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, fd);
}
// 4) otherwise field lookup fails
return nullptr;
}
Klass* InstanceKlass::find_field(Symbol* name, Symbol* sig, bool is_static, fieldDescriptor* fd) const {
// search order according to newest JVM spec (5.4.3.2, p.167).
// 1) search for field in current klass
if (find_local_field(name, sig, fd)) {
if (fd->is_static() == is_static) return const_cast<InstanceKlass*>(this);
}
// 2) search for field recursively in direct superinterfaces
if (is_static) {
Klass* intf = find_interface_field(name, sig, fd);
if (intf != nullptr) return intf;
}
// 3) apply field lookup recursively if superclass exists
{ Klass* supr = super();
if (supr != nullptr) return InstanceKlass::cast(supr)->find_field(name, sig, is_static, fd);
}
// 4) otherwise field lookup fails
return nullptr;
}
bool InstanceKlass::find_local_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
if (fs.offset() == offset) {
fd->reinitialize(const_cast<InstanceKlass*>(this), fs.index());
if (fd->is_static() == is_static) return true;
}
}
return false;
}
bool InstanceKlass::find_field_from_offset(int offset, bool is_static, fieldDescriptor* fd) const {
Klass* klass = const_cast<InstanceKlass*>(this);
while (klass != nullptr) {
if (InstanceKlass::cast(klass)->find_local_field_from_offset(offset, is_static, fd)) {
return true;
}
klass = klass->super();
}
return false;
}
void InstanceKlass::methods_do(void f(Method* method)) {
// Methods aren't stable until they are loaded. This can be read outside
// a lock through the ClassLoaderData for profiling
// Redefined scratch classes are on the list and need to be cleaned
if (!is_loaded() && !is_scratch_class()) {
return;
}
int len = methods()->length();
for (int index = 0; index < len; index++) {
Method* m = methods()->at(index);
assert(m->is_method(), "must be method");
f(m);
}
}
void InstanceKlass::do_local_static_fields(FieldClosure* cl) {
for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
if (fs.access_flags().is_static()) {
fieldDescriptor& fd = fs.field_descriptor();
cl->do_field(&fd);
}
}
}
void InstanceKlass::do_local_static_fields(void f(fieldDescriptor*, Handle, TRAPS), Handle mirror, TRAPS) {
for (JavaFieldStream fs(this); !fs.done(); fs.next()) {
if (fs.access_flags().is_static()) {
fieldDescriptor& fd = fs.field_descriptor();
f(&fd, mirror, CHECK);
}
}
}
void InstanceKlass::do_nonstatic_fields(FieldClosure* cl) {
InstanceKlass* super = superklass();
if (super != nullptr) {
super->do_nonstatic_fields(cl);
}
fieldDescriptor fd;
int length = java_fields_count();
for (int i = 0; i < length; i += 1) {
fd.reinitialize(this, i);
if (!fd.is_static()) {
cl->do_field(&fd);
}
}
}
// first in Pair is offset, second is index.
static int compare_fields_by_offset(Pair<int,int>* a, Pair<int,int>* b) {
return a->first - b->first;
}
void InstanceKlass::print_nonstatic_fields(FieldClosure* cl) {
InstanceKlass* super = superklass();
if (super != nullptr) {
super->print_nonstatic_fields(cl);
}
ResourceMark rm;
fieldDescriptor fd;
// In DebugInfo nonstatic fields are sorted by offset.
GrowableArray<Pair<int,int> > fields_sorted;
int i = 0;
for (AllFieldStream fs(this); !fs.done(); fs.next()) {
if (!fs.access_flags().is_static()) {
fd = fs.field_descriptor();
Pair<int,int> f(fs.offset(), fs.index());
fields_sorted.push(f);
i++;
}
}
if (i > 0) {
int length = i;
assert(length == fields_sorted.length(), "duh");
// _sort_Fn is defined in growableArray.hpp.
fields_sorted.sort(compare_fields_by_offset);
for (int i = 0; i < length; i++) {
fd.reinitialize(this, fields_sorted.at(i).second);
assert(!fd.is_static() && fd.offset() == fields_sorted.at(i).first, "only nonstatic fields");
cl->do_field(&fd);
}
}
}
#ifdef ASSERT
static int linear_search(const Array<Method*>* methods,
const Symbol* name,
const Symbol* signature) {
const int len = methods->length();
for (int index = 0; index < len; index++) {
const Method* const m = methods->at(index);
assert(m->is_method(), "must be method");
if (m->signature() == signature && m->name() == name) {
return index;
}
}
return -1;
}
#endif
bool InstanceKlass::_disable_method_binary_search = false;
NOINLINE int linear_search(const Array<Method*>* methods, const Symbol* name) {
int len = methods->length();
int l = 0;
int h = len - 1;
while (l <= h) {
Method* m = methods->at(l);
if (m->name() == name) {
return l;
}
l++;
}
return -1;
}
inline int InstanceKlass::quick_search(const Array<Method*>* methods, const Symbol* name) {
if (_disable_method_binary_search) {
assert(DynamicDumpSharedSpaces, "must be");
// At the final stage of dynamic dumping, the methods array may not be sorted
// by ascending addresses of their names, so we can't use binary search anymore.
// However, methods with the same name are still laid out consecutively inside the
// methods array, so let's look for the first one that matches.
return linear_search(methods, name);
}
int len = methods->length();
int l = 0;
int h = len - 1;
// methods are sorted by ascending addresses of their names, so do binary search
while (l <= h) {
int mid = (l + h) >> 1;
Method* m = methods->at(mid);
assert(m->is_method(), "must be method");
int res = m->name()->fast_compare(name);
if (res == 0) {
return mid;
} else if (res < 0) {
l = mid + 1;
} else {
h = mid - 1;
}
}
return -1;
}
// find_method looks up the name/signature in the local methods array
Method* InstanceKlass::find_method(const Symbol* name,
const Symbol* signature) const {
return find_method_impl(name, signature,
OverpassLookupMode::find,
StaticLookupMode::find,
PrivateLookupMode::find);
}
Method* InstanceKlass::find_method_impl(const Symbol* name,
const Symbol* signature,
OverpassLookupMode overpass_mode,
StaticLookupMode static_mode,
PrivateLookupMode private_mode) const {
return InstanceKlass::find_method_impl(methods(),
name,
signature,
overpass_mode,
static_mode,
private_mode);
}
// find_instance_method looks up the name/signature in the local methods array
// and skips over static methods
Method* InstanceKlass::find_instance_method(const Array<Method*>* methods,
const Symbol* name,
const Symbol* signature,
PrivateLookupMode private_mode) {
Method* const meth = InstanceKlass::find_method_impl(methods,
name,
signature,
OverpassLookupMode::find,
StaticLookupMode::skip,
private_mode);
assert(((meth == nullptr) || !meth->is_static()),
"find_instance_method should have skipped statics");
return meth;
}
// find_instance_method looks up the name/signature in the local methods array
// and skips over static methods
Method* InstanceKlass::find_instance_method(const Symbol* name,
const Symbol* signature,
PrivateLookupMode private_mode) const {
return InstanceKlass::find_instance_method(methods(), name, signature, private_mode);
}
// Find looks up the name/signature in the local methods array
// and filters on the overpass, static and private flags
// This returns the first one found
// note that the local methods array can have up to one overpass, one static
// and one instance (private or not) with the same name/signature
Method* InstanceKlass::find_local_method(const Symbol* name,
const Symbol* signature,
OverpassLookupMode overpass_mode,
StaticLookupMode static_mode,
PrivateLookupMode private_mode) const {
return InstanceKlass::find_method_impl(methods(),
name,
signature,
overpass_mode,
static_mode,
private_mode);
}
// Find looks up the name/signature in the local methods array
// and filters on the overpass, static and private flags
// This returns the first one found
// note that the local methods array can have up to one overpass, one static
// and one instance (private or not) with the same name/signature
Method* InstanceKlass::find_local_method(const Array<Method*>* methods,
const Symbol* name,
const Symbol* signature,
OverpassLookupMode overpass_mode,
StaticLookupMode static_mode,
PrivateLookupMode private_mode) {
return InstanceKlass::find_method_impl(methods,
name,
signature,
overpass_mode,
static_mode,
private_mode);
}
Method* InstanceKlass::find_method(const Array<Method*>* methods,
const Symbol* name,
const Symbol* signature) {
return InstanceKlass::find_method_impl(methods,
name,
signature,
OverpassLookupMode::find,
StaticLookupMode::find,
PrivateLookupMode::find);
}
Method* InstanceKlass::find_method_impl(const Array<Method*>* methods,
const Symbol* name,
const Symbol* signature,
OverpassLookupMode overpass_mode,
StaticLookupMode static_mode,
PrivateLookupMode private_mode) {
int hit = find_method_index(methods, name, signature, overpass_mode, static_mode, private_mode);
return hit >= 0 ? methods->at(hit): nullptr;
}
// true if method matches signature and conforms to skipping_X conditions.
static bool method_matches(const Method* m,
const Symbol* signature,
bool skipping_overpass,
bool skipping_static,
bool skipping_private) {
return ((m->signature() == signature) &&
(!skipping_overpass || !m->is_overpass()) &&
(!skipping_static || !m->is_static()) &&
(!skipping_private || !m->is_private()));
}
// Used directly for default_methods to find the index into the
// default_vtable_indices, and indirectly by find_method
// find_method_index looks in the local methods array to return the index
// of the matching name/signature. If, overpass methods are being ignored,
// the search continues to find a potential non-overpass match. This capability
// is important during method resolution to prefer a static method, for example,
// over an overpass method.
// There is the possibility in any _method's array to have the same name/signature
// for a static method, an overpass method and a local instance method
// To correctly catch a given method, the search criteria may need
// to explicitly skip the other two. For local instance methods, it
// is often necessary to skip private methods
int InstanceKlass::find_method_index(const Array<Method*>* methods,
const Symbol* name,
const Symbol* signature,
OverpassLookupMode overpass_mode,
StaticLookupMode static_mode,
PrivateLookupMode private_mode) {
const bool skipping_overpass = (overpass_mode == OverpassLookupMode::skip);
const bool skipping_static = (static_mode == StaticLookupMode::skip);
const bool skipping_private = (private_mode == PrivateLookupMode::skip);
const int hit = quick_search(methods, name);
if (hit != -1) {
const Method* const m = methods->at(hit);
// Do linear search to find matching signature. First, quick check
// for common case, ignoring overpasses if requested.
if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
return hit;
}
// search downwards through overloaded methods
int i;
for (i = hit - 1; i >= 0; --i) {
const Method* const m = methods->at(i);
assert(m->is_method(), "must be method");
if (m->name() != name) {
break;
}
if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
return i;
}
}
// search upwards
for (i = hit + 1; i < methods->length(); ++i) {
const Method* const m = methods->at(i);
assert(m->is_method(), "must be method");
if (m->name() != name) {
break;
}
if (method_matches(m, signature, skipping_overpass, skipping_static, skipping_private)) {
return i;
}
}
// not found
#ifdef ASSERT
const int index = (skipping_overpass || skipping_static || skipping_private) ? -1 :
linear_search(methods, name, signature);
assert(-1 == index, "binary search should have found entry %d", index);
#endif
}
return -1;
}
int InstanceKlass::find_method_by_name(const Symbol* name, int* end) const {
return find_method_by_name(methods(), name, end);
}
int InstanceKlass::find_method_by_name(const Array<Method*>* methods,
const Symbol* name,
int* end_ptr) {
assert(end_ptr != nullptr, "just checking");
int start = quick_search(methods, name);
int end = start + 1;
if (start != -1) {
while (start - 1 >= 0 && (methods->at(start - 1))->name() == name) --start;
while (end < methods->length() && (methods->at(end))->name() == name) ++end;
*end_ptr = end;
return start;
}
return -1;
}
// uncached_lookup_method searches both the local class methods array and all
// superclasses methods arrays, skipping any overpass methods in superclasses,
// and possibly skipping private methods.
Method* InstanceKlass::uncached_lookup_method(const Symbol* name,
const Symbol* signature,
OverpassLookupMode overpass_mode,
PrivateLookupMode private_mode) const {
OverpassLookupMode overpass_local_mode = overpass_mode;
const Klass* klass = this;
while (klass != nullptr) {
Method* const method = InstanceKlass::cast(klass)->find_method_impl(name,
signature,
overpass_local_mode,
StaticLookupMode::find,
private_mode);
if (method != nullptr) {
return method;
}
klass = klass->super();
overpass_local_mode = OverpassLookupMode::skip; // Always ignore overpass methods in superclasses
}
return nullptr;
}
#ifdef ASSERT
// search through class hierarchy and return true if this class or
// one of the superclasses was redefined
bool InstanceKlass::has_redefined_this_or_super() const {
const Klass* klass = this;
while (klass != nullptr) {
if (InstanceKlass::cast(klass)->has_been_redefined()) {
return true;
}
klass = klass->super();
}
return false;
}
#endif
// lookup a method in the default methods list then in all transitive interfaces
// Do NOT return private or static methods
Method* InstanceKlass::lookup_method_in_ordered_interfaces(Symbol* name,
Symbol* signature) const {
Method* m = nullptr;
if (default_methods() != nullptr) {
m = find_method(default_methods(), name, signature);
}
// Look up interfaces
if (m == nullptr) {
m = lookup_method_in_all_interfaces(name, signature, DefaultsLookupMode::find);
}
return m;
}
// lookup a method in all the interfaces that this class implements
// Do NOT return private or static methods, new in JDK8 which are not externally visible
// They should only be found in the initial InterfaceMethodRef
Method* InstanceKlass::lookup_method_in_all_interfaces(Symbol* name,
Symbol* signature,
DefaultsLookupMode defaults_mode) const {
Array<InstanceKlass*>* all_ifs = transitive_interfaces();
int num_ifs = all_ifs->length();
InstanceKlass *ik = nullptr;
for (int i = 0; i < num_ifs; i++) {
ik = all_ifs->at(i);
Method* m = ik->lookup_method(name, signature);
if (m != nullptr && m->is_public() && !m->is_static() &&
((defaults_mode != DefaultsLookupMode::skip) || !m->is_default_method())) {
return m;
}
}
return nullptr;
}
PrintClassClosure::PrintClassClosure(outputStream* st, bool verbose)
:_st(st), _verbose(verbose) {
ResourceMark rm;
_st->print("%-18s ", "KlassAddr");
_st->print("%-4s ", "Size");
_st->print("%-20s ", "State");
_st->print("%-7s ", "Flags");
_st->print("%-5s ", "ClassName");
_st->cr();
}
void PrintClassClosure::do_klass(Klass* k) {
ResourceMark rm;
// klass pointer
_st->print(PTR_FORMAT " ", p2i(k));
// klass size
_st->print("%4d ", k->size());
// initialization state
if (k->is_instance_klass()) {
_st->print("%-20s ",InstanceKlass::cast(k)->init_state_name());
} else {
_st->print("%-20s ","");
}
// misc flags(Changes should synced with ClassesDCmd::ClassesDCmd help doc)
char buf[10];
int i = 0;
if (k->has_finalizer()) buf[i++] = 'F';
if (k->is_instance_klass()) {
InstanceKlass* ik = InstanceKlass::cast(k);
if (ik->has_final_method()) buf[i++] = 'f';
if (ik->is_rewritten()) buf[i++] = 'W';
if (ik->is_contended()) buf[i++] = 'C';
if (ik->has_been_redefined()) buf[i++] = 'R';
if (ik->is_shared()) buf[i++] = 'S';
}
buf[i++] = '\0';
_st->print("%-7s ", buf);
// klass name
_st->print("%-5s ", k->external_name());
// end
_st->cr();
if (_verbose) {
k->print_on(_st);
}
}
/* jni_id_for for jfieldIds only */
JNIid* InstanceKlass::jni_id_for(int offset) {
MutexLocker ml(JfieldIdCreation_lock);
JNIid* probe = jni_ids() == nullptr ? nullptr : jni_ids()->find(offset);
if (probe == nullptr) {
// Allocate new static field identifier
probe = new JNIid(this, offset, jni_ids());
set_jni_ids(probe);
}
return probe;
}
u2 InstanceKlass::enclosing_method_data(int offset) const {
const Array<jushort>* const inner_class_list = inner_classes();
if (inner_class_list == nullptr) {
return 0;
}
const int length = inner_class_list->length();
if (length % inner_class_next_offset == 0) {
return 0;
}
const int index = length - enclosing_method_attribute_size;
assert(offset < enclosing_method_attribute_size, "invalid offset");
return inner_class_list->at(index + offset);
}
void InstanceKlass::set_enclosing_method_indices(u2 class_index,
u2 method_index) {
Array<jushort>* inner_class_list = inner_classes();
assert (inner_class_list != nullptr, "_inner_classes list is not set up");
int length = inner_class_list->length();
if (length % inner_class_next_offset == enclosing_method_attribute_size) {
int index = length - enclosing_method_attribute_size;
inner_class_list->at_put(
index + enclosing_method_class_index_offset, class_index);
inner_class_list->at_put(
index + enclosing_method_method_index_offset, method_index);
}
}
// Lookup or create a jmethodID.
// This code is called by the VMThread and JavaThreads so the
// locking has to be done very carefully to avoid deadlocks
// and/or other cache consistency problems.
//
jmethodID InstanceKlass::get_jmethod_id(const methodHandle& method_h) {
size_t idnum = (size_t)method_h->method_idnum();
jmethodID* jmeths = methods_jmethod_ids_acquire();
size_t length = 0;
jmethodID id = nullptr;
// We use a double-check locking idiom here because this cache is
// performance sensitive. In the normal system, this cache only
// transitions from null to non-null which is safe because we use
// release_set_methods_jmethod_ids() to advertise the new cache.
// A partially constructed cache should never be seen by a racing
// thread. We also use release_store() to save a new jmethodID
// in the cache so a partially constructed jmethodID should never be
// seen either. Cache reads of existing jmethodIDs proceed without a
// lock, but cache writes of a new jmethodID requires uniqueness and
// creation of the cache itself requires no leaks so a lock is
// generally acquired in those two cases.
//
// If the RedefineClasses() API has been used, then this cache can
// grow and we'll have transitions from non-null to bigger non-null.
// Cache creation requires no leaks and we require safety between all
// cache accesses and freeing of the old cache so a lock is generally
// acquired when the RedefineClasses() API has been used.
if (jmeths != nullptr) {
// the cache already exists
if (!idnum_can_increment()) {
// the cache can't grow so we can just get the current values
get_jmethod_id_length_value(jmeths, idnum, &length, &id);
} else {
MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
get_jmethod_id_length_value(jmeths, idnum, &length, &id);
}
}
// implied else:
// we need to allocate a cache so default length and id values are good
if (jmeths == nullptr || // no cache yet
length <= idnum || // cache is too short
id == nullptr) { // cache doesn't contain entry
// This function can be called by the VMThread or GC worker threads so we
// have to do all things that might block on a safepoint before grabbing the lock.
// Otherwise, we can deadlock with the VMThread or have a cache
// consistency issue. These vars keep track of what we might have
// to free after the lock is dropped.
jmethodID to_dealloc_id = nullptr;
jmethodID* to_dealloc_jmeths = nullptr;
// may not allocate new_jmeths or use it if we allocate it
jmethodID* new_jmeths = nullptr;
if (length <= idnum) {
// allocate a new cache that might be used
size_t size = MAX2(idnum+1, (size_t)idnum_allocated_count());
new_jmeths = NEW_C_HEAP_ARRAY(jmethodID, size+1, mtClass);
memset(new_jmeths, 0, (size+1)*sizeof(jmethodID));
// cache size is stored in element[0], other elements offset by one
new_jmeths[0] = (jmethodID)size;
}
// allocate a new jmethodID that might be used
{
MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
jmethodID new_id = nullptr;
if (method_h->is_old() && !method_h->is_obsolete()) {
// The method passed in is old (but not obsolete), we need to use the current version
Method* current_method = method_with_idnum((int)idnum);
assert(current_method != nullptr, "old and but not obsolete, so should exist");
new_id = Method::make_jmethod_id(class_loader_data(), current_method);
} else {
// It is the current version of the method or an obsolete method,
// use the version passed in
new_id = Method::make_jmethod_id(class_loader_data(), method_h());
}
id = get_jmethod_id_fetch_or_update(idnum, new_id, new_jmeths,
&to_dealloc_id, &to_dealloc_jmeths);
}
// The lock has been dropped so we can free resources.
// Free up either the old cache or the new cache if we allocated one.
if (to_dealloc_jmeths != nullptr) {
FreeHeap(to_dealloc_jmeths);
}
// free up the new ID since it wasn't needed
if (to_dealloc_id != nullptr) {
Method::destroy_jmethod_id(class_loader_data(), to_dealloc_id);
}
}
return id;
}
// Figure out how many jmethodIDs haven't been allocated, and make
// sure space for them is pre-allocated. This makes getting all
// method ids much, much faster with classes with more than 8
// methods, and has a *substantial* effect on performance with jvmti
// code that loads all jmethodIDs for all classes.
void InstanceKlass::ensure_space_for_methodids(int start_offset) {
int new_jmeths = 0;
int length = methods()->length();
for (int index = start_offset; index < length; index++) {
Method* m = methods()->at(index);
jmethodID id = m->find_jmethod_id_or_null();
if (id == nullptr) {
new_jmeths++;
}
}
if (new_jmeths != 0) {
Method::ensure_jmethod_ids(class_loader_data(), new_jmeths);
}
}
// Common code to fetch the jmethodID from the cache or update the
// cache with the new jmethodID. This function should never do anything
// that causes the caller to go to a safepoint or we can deadlock with
// the VMThread or have cache consistency issues.
//
jmethodID InstanceKlass::get_jmethod_id_fetch_or_update(
size_t idnum, jmethodID new_id,
jmethodID* new_jmeths, jmethodID* to_dealloc_id_p,
jmethodID** to_dealloc_jmeths_p) {
assert(new_id != nullptr, "sanity check");
assert(to_dealloc_id_p != nullptr, "sanity check");
assert(to_dealloc_jmeths_p != nullptr, "sanity check");
assert(JmethodIdCreation_lock->owned_by_self(), "sanity check");
// reacquire the cache - we are locked, single threaded or at a safepoint
jmethodID* jmeths = methods_jmethod_ids_acquire();
jmethodID id = nullptr;
size_t length = 0;
if (jmeths == nullptr || // no cache yet
(length = (size_t)jmeths[0]) <= idnum) { // cache is too short
if (jmeths != nullptr) {
// copy any existing entries from the old cache
for (size_t index = 0; index < length; index++) {
new_jmeths[index+1] = jmeths[index+1];
}
*to_dealloc_jmeths_p = jmeths; // save old cache for later delete
}
release_set_methods_jmethod_ids(jmeths = new_jmeths);
} else {
// fetch jmethodID (if any) from the existing cache
id = jmeths[idnum+1];
*to_dealloc_jmeths_p = new_jmeths; // save new cache for later delete
}
if (id == nullptr) {
// No matching jmethodID in the existing cache or we have a new
// cache or we just grew the cache. This cache write is done here
// by the first thread to win the foot race because a jmethodID
// needs to be unique once it is generally available.
id = new_id;
// The jmethodID cache can be read while unlocked so we have to
// make sure the new jmethodID is complete before installing it
// in the cache.
Atomic::release_store(&jmeths[idnum+1], id);
} else {
*to_dealloc_id_p = new_id; // save new id for later delete
}
return id;
}
// Common code to get the jmethodID cache length and the jmethodID
// value at index idnum if there is one.
//
void InstanceKlass::get_jmethod_id_length_value(jmethodID* cache,
size_t idnum, size_t *length_p, jmethodID* id_p) {
assert(cache != nullptr, "sanity check");
assert(length_p != nullptr, "sanity check");
assert(id_p != nullptr, "sanity check");
// cache size is stored in element[0], other elements offset by one
*length_p = (size_t)cache[0];
if (*length_p <= idnum) { // cache is too short
*id_p = nullptr;
} else {
*id_p = cache[idnum+1]; // fetch jmethodID (if any)
}
}
// Lookup a jmethodID, null if not found. Do no blocking, no allocations, no handles
jmethodID InstanceKlass::jmethod_id_or_null(Method* method) {
size_t idnum = (size_t)method->method_idnum();
jmethodID* jmeths = methods_jmethod_ids_acquire();
size_t length; // length assigned as debugging crumb
jmethodID id = nullptr;
if (jmeths != nullptr && // If there is a cache
(length = (size_t)jmeths[0]) > idnum) { // and if it is long enough,
id = jmeths[idnum+1]; // Look up the id (may be null)
}
return id;
}
inline DependencyContext InstanceKlass::dependencies() {
DependencyContext dep_context(&_dep_context, &_dep_context_last_cleaned);
return dep_context;
}
void InstanceKlass::mark_dependent_nmethods(DeoptimizationScope* deopt_scope, KlassDepChange& changes) {
dependencies().mark_dependent_nmethods(deopt_scope, changes);
}
void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
dependencies().add_dependent_nmethod(nm);
}
void InstanceKlass::clean_dependency_context() {
dependencies().clean_unloading_dependents();
}
#ifndef PRODUCT
void InstanceKlass::print_dependent_nmethods(bool verbose) {
dependencies().print_dependent_nmethods(verbose);
}
bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
return dependencies().is_dependent_nmethod(nm);
}
#endif //PRODUCT
void InstanceKlass::clean_weak_instanceklass_links() {
clean_implementors_list();
clean_method_data();
}
void InstanceKlass::clean_implementors_list() {
assert(is_loader_alive(), "this klass should be live");
if (is_interface()) {
assert (ClassUnloading, "only called for ClassUnloading");
for (;;) {
// Use load_acquire due to competing with inserts
InstanceKlass* impl = Atomic::load_acquire(adr_implementor());
if (impl != nullptr && !impl->is_loader_alive()) {
// null this field, might be an unloaded instance klass or null
InstanceKlass* volatile* iklass = adr_implementor();
if (Atomic::cmpxchg(iklass, impl, (InstanceKlass*)nullptr) == impl) {
// Successfully unlinking implementor.
if (log_is_enabled(Trace, class, unload)) {
ResourceMark rm;
log_trace(class, unload)("unlinking class (implementor): %s", impl->external_name());
}
return;
}
} else {
return;
}
}
}
}
void InstanceKlass::clean_method_data() {
for (int m = 0; m < methods()->length(); m++) {
MethodData* mdo = methods()->at(m)->method_data();
if (mdo != nullptr) {
MutexLocker ml(SafepointSynchronize::is_at_safepoint() ? nullptr : mdo->extra_data_lock());
mdo->clean_method_data(/*always_clean*/false);
}
}
}
void InstanceKlass::metaspace_pointers_do(MetaspaceClosure* it) {
Klass::metaspace_pointers_do(it);
if (log_is_enabled(Trace, cds)) {
ResourceMark rm;
log_trace(cds)("Iter(InstanceKlass): %p (%s)", this, external_name());
}
it->push(&_annotations);
it->push((Klass**)&_array_klasses);
if (!is_rewritten()) {
it->push(&_constants, MetaspaceClosure::_writable);
} else {
it->push(&_constants);
}
it->push(&_inner_classes);
#if INCLUDE_JVMTI
it->push(&_previous_versions);
#endif
#if INCLUDE_CDS
// For "old" classes with methods containing the jsr bytecode, the _methods array will
// be rewritten during runtime (see Rewriter::rewrite_jsrs()). So setting the _methods to
// be writable. The length check on the _methods is necessary because classes which
// don't have any methods share the Universe::_the_empty_method_array which is in the RO region.
if (_methods != nullptr && _methods->length() > 0 &&
!can_be_verified_at_dumptime() && methods_contain_jsr_bytecode()) {
// To handle jsr bytecode, new Method* maybe stored into _methods
it->push(&_methods, MetaspaceClosure::_writable);
} else {
#endif
it->push(&_methods);
#if INCLUDE_CDS
}
#endif
it->push(&_default_methods);
it->push(&_local_interfaces);
it->push(&_transitive_interfaces);
it->push(&_method_ordering);
if (!is_rewritten()) {
it->push(&_default_vtable_indices, MetaspaceClosure::_writable);
} else {
it->push(&_default_vtable_indices);
}
it->push(&_fieldinfo_stream);
// _fields_status might be written into by Rewriter::scan_method() -> fd.set_has_initialized_final_update()
it->push(&_fields_status, MetaspaceClosure::_writable);
if (itable_length() > 0) {
itableOffsetEntry* ioe = (itableOffsetEntry*)start_of_itable();
int method_table_offset_in_words = ioe->offset()/wordSize;
int itable_offset_in_words = (int)(start_of_itable() - (intptr_t*)this);
int nof_interfaces = (method_table_offset_in_words - itable_offset_in_words)
/ itableOffsetEntry::size();
for (int i = 0; i < nof_interfaces; i ++, ioe ++) {
if (ioe->interface_klass() != nullptr) {
it->push(ioe->interface_klass_addr());
itableMethodEntry* ime = ioe->first_method_entry(this);
int n = klassItable::method_count_for_interface(ioe->interface_klass());
for (int index = 0; index < n; index ++) {
it->push(ime[index].method_addr());
}
}
}
}
it->push(&_nest_members);
it->push(&_permitted_subclasses);
it->push(&_record_components);
}
#if INCLUDE_CDS
void InstanceKlass::remove_unshareable_info() {
if (is_linked()) {
assert(can_be_verified_at_dumptime(), "must be");
// Remember this so we can avoid walking the hierarchy at runtime.
set_verified_at_dump_time();
}
Klass::remove_unshareable_info();
if (SystemDictionaryShared::has_class_failed_verification(this)) {
// Classes are attempted to link during dumping and may fail,
// but these classes are still in the dictionary and class list in CLD.
// If the class has failed verification, there is nothing else to remove.
return;
}
// Reset to the 'allocated' state to prevent any premature accessing to
// a shared class at runtime while the class is still being loaded and
// restored. A class' init_state is set to 'loaded' at runtime when it's
// being added to class hierarchy (see InstanceKlass:::add_to_hierarchy()).
_init_state = allocated;
{ // Otherwise this needs to take out the Compile_lock.
assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
init_implementor();
}
constants()->remove_unshareable_info();
for (int i = 0; i < methods()->length(); i++) {
Method* m = methods()->at(i);
m->remove_unshareable_info();
}
// do array classes also.
if (array_klasses() != nullptr) {
array_klasses()->remove_unshareable_info();
}
// These are not allocated from metaspace. They are safe to set to null.
_source_debug_extension = nullptr;
_dep_context = nullptr;
_osr_nmethods_head = nullptr;
#if INCLUDE_JVMTI
_breakpoints = nullptr;
_previous_versions = nullptr;
_cached_class_file = nullptr;
_jvmti_cached_class_field_map = nullptr;
#endif
_init_thread = nullptr;
_methods_jmethod_ids = nullptr;
_jni_ids = nullptr;
_oop_map_cache = nullptr;
// clear _nest_host to ensure re-load at runtime
_nest_host = nullptr;
init_shared_package_entry();
_dep_context_last_cleaned = 0;
_init_monitor = nullptr;
remove_unshareable_flags();
}
void InstanceKlass::remove_unshareable_flags() {
// clear all the flags/stats that shouldn't be in the archived version
assert(!is_scratch_class(), "must be");
assert(!has_been_redefined(), "must be");
#if INCLUDE_JVMTI
set_is_being_redefined(false);
#endif
set_has_resolved_methods(false);
}
void InstanceKlass::remove_java_mirror() {
Klass::remove_java_mirror();
// do array classes also.
if (array_klasses() != nullptr) {
array_klasses()->remove_java_mirror();
}
}
void InstanceKlass::init_shared_package_entry() {
#if !INCLUDE_CDS_JAVA_HEAP
_package_entry = nullptr;
#else
if (!MetaspaceShared::use_full_module_graph()) {
_package_entry = nullptr;
} else if (DynamicDumpSharedSpaces) {
if (!MetaspaceShared::is_in_shared_metaspace(_package_entry)) {
_package_entry = nullptr;
}
} else {
if (is_shared_unregistered_class()) {
_package_entry = nullptr;
} else {
_package_entry = PackageEntry::get_archived_entry(_package_entry);
}
}
ArchivePtrMarker::mark_pointer((address**)&_package_entry);
#endif
}
void InstanceKlass::compute_has_loops_flag_for_methods() {
Array<Method*>* methods = this->methods();
for (int index = 0; index < methods->length(); ++index) {
Method* m = methods->at(index);
if (!m->is_overpass()) { // work around JDK-8305771
m->compute_has_loops_flag();
}
}
}
void InstanceKlass::restore_unshareable_info(ClassLoaderData* loader_data, Handle protection_domain,
PackageEntry* pkg_entry, TRAPS) {
// InstanceKlass::add_to_hierarchy() sets the init_state to loaded
// before the InstanceKlass is added to the SystemDictionary. Make
// sure the current state is <loaded.
assert(!is_loaded(), "invalid init state");
assert(!shared_loading_failed(), "Must not try to load failed class again");
set_package(loader_data, pkg_entry, CHECK);
Klass::restore_unshareable_info(loader_data, protection_domain, CHECK);
Array<Method*>* methods = this->methods();
int num_methods = methods->length();
for (int index = 0; index < num_methods; ++index) {
methods->at(index)->restore_unshareable_info(CHECK);
}
#if INCLUDE_JVMTI
if (JvmtiExport::has_redefined_a_class()) {
// Reinitialize vtable because RedefineClasses may have changed some
// entries in this vtable for super classes so the CDS vtable might
// point to old or obsolete entries. RedefineClasses doesn't fix up
// vtables in the shared system dictionary, only the main one.
// It also redefines the itable too so fix that too.
// First fix any default methods that point to a super class that may
// have been redefined.
bool trace_name_printed = false;
adjust_default_methods(&trace_name_printed);
vtable().initialize_vtable();
itable().initialize_itable();
}
#endif
// restore constant pool resolved references
constants()->restore_unshareable_info(CHECK);
if (array_klasses() != nullptr) {
// To get a consistent list of classes we need MultiArray_lock to ensure
// array classes aren't observed while they are being restored.
MutexLocker ml(MultiArray_lock);
// Array classes have null protection domain.
// --> see ArrayKlass::complete_create_array_klass()
array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
}
// Initialize @ValueBased class annotation
if (DiagnoseSyncOnValueBasedClasses && has_value_based_class_annotation()) {
set_is_value_based();
}
// restore the monitor
_init_monitor = create_init_monitor("InstanceKlassInitMonitorRestored_lock");
}
// Check if a class or any of its supertypes has a version older than 50.
// CDS will not perform verification of old classes during dump time because
// without changing the old verifier, the verification constraint cannot be
// retrieved during dump time.
// Verification of archived old classes will be performed during run time.
bool InstanceKlass::can_be_verified_at_dumptime() const {
if (MetaspaceShared::is_in_shared_metaspace(this)) {
// This is a class that was dumped into the base archive, so we know
// it was verified at dump time.
return true;
}
if (major_version() < 50 /*JAVA_6_VERSION*/) {
return false;
}
if (java_super() != nullptr && !java_super()->can_be_verified_at_dumptime()) {
return false;
}
Array<InstanceKlass*>* interfaces = local_interfaces();
int len = interfaces->length();
for (int i = 0; i < len; i++) {
if (!interfaces->at(i)->can_be_verified_at_dumptime()) {
return false;
}
}
return true;
}
bool InstanceKlass::methods_contain_jsr_bytecode() const {
Thread* thread = Thread::current();
for (int i = 0; i < _methods->length(); i++) {
methodHandle m(thread, _methods->at(i));
BytecodeStream bcs(m);
while (!bcs.is_last_bytecode()) {
Bytecodes::Code opcode = bcs.next();
if (opcode == Bytecodes::_jsr || opcode == Bytecodes::_jsr_w) {
return true;
}
}
}
return false;
}
#endif // INCLUDE_CDS
#if INCLUDE_JVMTI
static void clear_all_breakpoints(Method* m) {
m->clear_all_breakpoints();
}
#endif
void InstanceKlass::unload_class(InstanceKlass* ik) {
// Release dependencies.
ik->dependencies().remove_all_dependents();
// notify the debugger
if (JvmtiExport::should_post_class_unload()) {
JvmtiExport::post_class_unload(ik);
}
// notify ClassLoadingService of class unload
ClassLoadingService::notify_class_unloaded(ik);
SystemDictionaryShared::handle_class_unloading(ik);
if (log_is_enabled(Info, class, unload)) {
ResourceMark rm;
log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
}
Events::log_class_unloading(Thread::current(), ik);
#if INCLUDE_JFR
assert(ik != nullptr, "invariant");
EventClassUnload event;
event.set_unloadedClass(ik);
event.set_definingClassLoader(ik->class_loader_data());
event.commit();
#endif
}
static void method_release_C_heap_structures(Method* m) {
m->release_C_heap_structures();
}
// Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.
void InstanceKlass::release_C_heap_structures(bool release_sub_metadata) {
// Clean up C heap
Klass::release_C_heap_structures();
// Deallocate and call destructors for MDO mutexes
if (release_sub_metadata) {
methods_do(method_release_C_heap_structures);
}
// Destroy the init_monitor
delete _init_monitor;
// Deallocate oop map cache
if (_oop_map_cache != nullptr) {
delete _oop_map_cache;
_oop_map_cache = nullptr;
}
// Deallocate JNI identifiers for jfieldIDs
JNIid::deallocate(jni_ids());
set_jni_ids(nullptr);
jmethodID* jmeths = methods_jmethod_ids_acquire();
if (jmeths != (jmethodID*)nullptr) {
release_set_methods_jmethod_ids(nullptr);
FreeHeap(jmeths);
}
assert(_dep_context == nullptr,
"dependencies should already be cleaned");
#if INCLUDE_JVMTI
// Deallocate breakpoint records
if (breakpoints() != 0x0) {
methods_do(clear_all_breakpoints);
assert(breakpoints() == 0x0, "should have cleared breakpoints");
}
// deallocate the cached class file
if (_cached_class_file != nullptr) {
os::free(_cached_class_file);
_cached_class_file = nullptr;
}
#endif
FREE_C_HEAP_ARRAY(char, _source_debug_extension);
if (release_sub_metadata) {
constants()->release_C_heap_structures();
}
}
void InstanceKlass::set_source_debug_extension(const char* array, int length) {
if (array == nullptr) {
_source_debug_extension = nullptr;
} else {
// Adding one to the attribute length in order to store a null terminator
// character could cause an overflow because the attribute length is
// already coded with an u4 in the classfile, but in practice, it's
// unlikely to happen.
assert((length+1) > length, "Overflow checking");
char* sde = NEW_C_HEAP_ARRAY(char, (length + 1), mtClass);
for (int i = 0; i < length; i++) {
sde[i] = array[i];
}
sde[length] = '\0';
_source_debug_extension = sde;
}
}
const char* InstanceKlass::signature_name() const {
// Get the internal name as a c string
const char* src = (const char*) (name()->as_C_string());
const int src_length = (int)strlen(src);
char* dest = NEW_RESOURCE_ARRAY(char, src_length + 3);
// Add L as type indicator
int dest_index = 0;
dest[dest_index++] = JVM_SIGNATURE_CLASS;
// Add the actual class name
for (int src_index = 0; src_index < src_length; ) {
dest[dest_index++] = src[src_index++];
}
if (is_hidden()) { // Replace the last '+' with a '.'.
for (int index = (int)src_length; index > 0; index--) {
if (dest[index] == '+') {
dest[index] = JVM_SIGNATURE_DOT;
break;
}
}
}
// Add the semicolon and the null
dest[dest_index++] = JVM_SIGNATURE_ENDCLASS;
dest[dest_index] = '\0';
return dest;
}
ModuleEntry* InstanceKlass::module() const {
if (is_hidden() &&
in_unnamed_package() &&
class_loader_data()->has_class_mirror_holder()) {
// For a non-strong hidden class defined to an unnamed package,
// its (class held) CLD will not have an unnamed module created for it.
// Two choices to find the correct ModuleEntry:
// 1. If hidden class is within a nest, use nest host's module
// 2. Find the unnamed module off from the class loader
// For now option #2 is used since a nest host is not set until
// after the instance class is created in jvm_lookup_define_class().
if (class_loader_data()->is_boot_class_loader_data()) {
return ClassLoaderData::the_null_class_loader_data()->unnamed_module();
} else {
oop module = java_lang_ClassLoader::unnamedModule(class_loader_data()->class_loader());
assert(java_lang_Module::is_instance(module), "Not an instance of java.lang.Module");
return java_lang_Module::module_entry(module);
}
}
// Class is in a named package
if (!in_unnamed_package()) {
return _package_entry->module();
}
// Class is in an unnamed package, return its loader's unnamed module
return class_loader_data()->unnamed_module();
}
void InstanceKlass::set_package(ClassLoaderData* loader_data, PackageEntry* pkg_entry, TRAPS) {
// ensure java/ packages only loaded by boot or platform builtin loaders
// not needed for shared class since CDS does not archive prohibited classes.
if (!is_shared()) {
check_prohibited_package(name(), loader_data, CHECK);
}
if (is_shared() && _package_entry != nullptr) {
if (MetaspaceShared::use_full_module_graph() && _package_entry == pkg_entry) {
// we can use the saved package
assert(MetaspaceShared::is_in_shared_metaspace(_package_entry), "must be");
return;
} else {
_package_entry = nullptr;
}
}
// ClassLoader::package_from_class_name has already incremented the refcount of the symbol
// it returns, so we need to decrement it when the current function exits.
TempNewSymbol from_class_name =
(pkg_entry != nullptr) ? nullptr : ClassLoader::package_from_class_name(name());
Symbol* pkg_name;
if (pkg_entry != nullptr) {
pkg_name = pkg_entry->name();
} else {
pkg_name = from_class_name;
}
if (pkg_name != nullptr && loader_data != nullptr) {
// Find in class loader's package entry table.
_package_entry = pkg_entry != nullptr ? pkg_entry : loader_data->packages()->lookup_only(pkg_name);
// If the package name is not found in the loader's package
// entry table, it is an indication that the package has not
// been defined. Consider it defined within the unnamed module.
if (_package_entry == nullptr) {
if (!ModuleEntryTable::javabase_defined()) {
// Before java.base is defined during bootstrapping, define all packages in
// the java.base module. If a non-java.base package is erroneously placed
// in the java.base module it will be caught later when java.base
// is defined by ModuleEntryTable::verify_javabase_packages check.
assert(ModuleEntryTable::javabase_moduleEntry() != nullptr, JAVA_BASE_NAME " module is null");
_package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, ModuleEntryTable::javabase_moduleEntry());
} else {
assert(loader_data->unnamed_module() != nullptr, "unnamed module is null");
_package_entry = loader_data->packages()->create_entry_if_absent(pkg_name, loader_data->unnamed_module());
}
// A package should have been successfully created
DEBUG_ONLY(ResourceMark rm(THREAD));
assert(_package_entry != nullptr, "Package entry for class %s not found, loader %s",
name()->as_C_string(), loader_data->loader_name_and_id());
}
if (log_is_enabled(Debug, module)) {
ResourceMark rm(THREAD);
ModuleEntry* m = _package_entry->module();
log_trace(module)("Setting package: class: %s, package: %s, loader: %s, module: %s",
external_name(),
pkg_name->as_C_string(),
loader_data->loader_name_and_id(),
(m->is_named() ? m->name()->as_C_string() : UNNAMED_MODULE));
}
} else {
ResourceMark rm(THREAD);
log_trace(module)("Setting package: class: %s, package: unnamed, loader: %s, module: %s",
external_name(),
(loader_data != nullptr) ? loader_data->loader_name_and_id() : "null",
UNNAMED_MODULE);
}
}
// Function set_classpath_index ensures that for a non-null _package_entry
// of the InstanceKlass, the entry is in the boot loader's package entry table.
// It then sets the classpath_index in the package entry record.
//
// The classpath_index field is used to find the entry on the boot loader class
// path for packages with classes loaded by the boot loader from -Xbootclasspath/a
// in an unnamed module. It is also used to indicate (for all packages whose
// classes are loaded by the boot loader) that at least one of the package's
// classes has been loaded.
void InstanceKlass::set_classpath_index(s2 path_index) {
if (_package_entry != nullptr) {
DEBUG_ONLY(PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();)
assert(pkg_entry_tbl->lookup_only(_package_entry->name()) == _package_entry, "Should be same");
assert(path_index != -1, "Unexpected classpath_index");
_package_entry->set_classpath_index(path_index);
}
}
// different versions of is_same_class_package
bool InstanceKlass::is_same_class_package(const Klass* class2) const {
oop classloader1 = this->class_loader();
PackageEntry* classpkg1 = this->package();
if (class2->is_objArray_klass()) {
class2 = ObjArrayKlass::cast(class2)->bottom_klass();
}
oop classloader2;
PackageEntry* classpkg2;
if (class2->is_instance_klass()) {
classloader2 = class2->class_loader();
classpkg2 = class2->package();
} else {
assert(class2->is_typeArray_klass(), "should be type array");
classloader2 = nullptr;
classpkg2 = nullptr;
}
// Same package is determined by comparing class loader
// and package entries. Both must be the same. This rule
// applies even to classes that are defined in the unnamed
// package, they still must have the same class loader.
if ((classloader1 == classloader2) && (classpkg1 == classpkg2)) {
return true;
}
return false;
}
// return true if this class and other_class are in the same package. Classloader
// and classname information is enough to determine a class's package
bool InstanceKlass::is_same_class_package(oop other_class_loader,
const Symbol* other_class_name) const {
if (class_loader() != other_class_loader) {
return false;
}
if (name()->fast_compare(other_class_name) == 0) {
return true;
}
{
ResourceMark rm;
bool bad_class_name = false;
TempNewSymbol other_pkg = ClassLoader::package_from_class_name(other_class_name, &bad_class_name);
if (bad_class_name) {
return false;
}
// Check that package_from_class_name() returns null, not "", if there is no package.
assert(other_pkg == nullptr || other_pkg->utf8_length() > 0, "package name is empty string");
const Symbol* const this_package_name =
this->package() != nullptr ? this->package()->name() : nullptr;
if (this_package_name == nullptr || other_pkg == nullptr) {
// One of the two doesn't have a package. Only return true if the other
// one also doesn't have a package.
return this_package_name == other_pkg;
}
// Check if package is identical
return this_package_name->fast_compare(other_pkg) == 0;
}
}
static bool is_prohibited_package_slow(Symbol* class_name) {
// Caller has ResourceMark
int length;
jchar* unicode = class_name->as_unicode(length);
return (length >= 5 &&
unicode[0] == 'j' &&
unicode[1] == 'a' &&
unicode[2] == 'v' &&
unicode[3] == 'a' &&
unicode[4] == '/');
}
// Only boot and platform class loaders can define classes in "java/" packages.
void InstanceKlass::check_prohibited_package(Symbol* class_name,
ClassLoaderData* loader_data,
TRAPS) {
if (!loader_data->is_boot_class_loader_data() &&
!loader_data->is_platform_class_loader_data() &&
class_name != nullptr && class_name->utf8_length() >= 5) {
ResourceMark rm(THREAD);
bool prohibited;
const u1* base = class_name->base();
if ((base[0] | base[1] | base[2] | base[3] | base[4]) & 0x80) {
prohibited = is_prohibited_package_slow(class_name);
} else {
char* name = class_name->as_C_string();
prohibited = (strncmp(name, JAVAPKG, JAVAPKG_LEN) == 0 && name[JAVAPKG_LEN] == '/');
}
if (prohibited) {
TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
assert(pkg_name != nullptr, "Error in parsing package name starting with 'java/'");
char* name = pkg_name->as_C_string();
const char* class_loader_name = loader_data->loader_name_and_id();
StringUtils::replace_no_expand(name, "/", ".");
const char* msg_text1 = "Class loader (instance of): ";
const char* msg_text2 = " tried to load prohibited package name: ";
size_t len = strlen(msg_text1) + strlen(class_loader_name) + strlen(msg_text2) + strlen(name) + 1;
char* message = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, len);
jio_snprintf(message, len, "%s%s%s%s", msg_text1, class_loader_name, msg_text2, name);
THROW_MSG(vmSymbols::java_lang_SecurityException(), message);
}
}
return;
}
bool InstanceKlass::find_inner_classes_attr(int* ooff, int* noff, TRAPS) const {
constantPoolHandle i_cp(THREAD, constants());
for (InnerClassesIterator iter(this); !iter.done(); iter.next()) {
int ioff = iter.inner_class_info_index();
if (ioff != 0) {
// Check to see if the name matches the class we're looking for
// before attempting to find the class.
if (i_cp->klass_name_at_matches(this, ioff)) {
Klass* inner_klass = i_cp->klass_at(ioff, CHECK_false);
if (this == inner_klass) {
*ooff = iter.outer_class_info_index();
*noff = iter.inner_name_index();
return true;
}
}
}
}
return false;
}
InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRAPS) const {
InstanceKlass* outer_klass = nullptr;
*inner_is_member = false;
int ooff = 0, noff = 0;
bool has_inner_classes_attr = find_inner_classes_attr(&ooff, &noff, THREAD);
if (has_inner_classes_attr) {
constantPoolHandle i_cp(THREAD, constants());
if (ooff != 0) {
Klass* ok = i_cp->klass_at(ooff, CHECK_NULL);
if (!ok->is_instance_klass()) {
// If the outer class is not an instance klass then it cannot have
// declared any inner classes.
ResourceMark rm(THREAD);
Exceptions::fthrow(
THREAD_AND_LOCATION,
vmSymbols::java_lang_IncompatibleClassChangeError(),
"%s and %s disagree on InnerClasses attribute",
ok->external_name(),
external_name());
return nullptr;
}
outer_klass = InstanceKlass::cast(ok);
*inner_is_member = true;
}
if (nullptr == outer_klass) {
// It may be a local class; try for that.
int encl_method_class_idx = enclosing_method_class_index();
if (encl_method_class_idx != 0) {
Klass* ok = i_cp->klass_at(encl_method_class_idx, CHECK_NULL);
outer_klass = InstanceKlass::cast(ok);
*inner_is_member = false;
}
}
}
// If no inner class attribute found for this class.
if (nullptr == outer_klass) return nullptr;
// Throws an exception if outer klass has not declared k as an inner klass
// We need evidence that each klass knows about the other, or else
// the system could allow a spoof of an inner class to gain access rights.
Reflection::check_for_inner_class(outer_klass, this, *inner_is_member, CHECK_NULL);
return outer_klass;
}
jint InstanceKlass::compute_modifier_flags() const {
jint access = access_flags().as_int();
// But check if it happens to be member class.
InnerClassesIterator iter(this);
for (; !iter.done(); iter.next()) {
int ioff = iter.inner_class_info_index();
// Inner class attribute can be zero, skip it.
// Strange but true: JVM spec. allows null inner class refs.
if (ioff == 0) continue;
// only look at classes that are already loaded
// since we are looking for the flags for our self.
Symbol* inner_name = constants()->klass_name_at(ioff);
if (name() == inner_name) {
// This is really a member class.
access = iter.inner_access_flags();
break;
}
}
// Remember to strip ACC_SUPER bit
return (access & (~JVM_ACC_SUPER)) & JVM_ACC_WRITTEN_FLAGS;
}
jint InstanceKlass::jvmti_class_status() const {
jint result = 0;
if (is_linked()) {
result |= JVMTI_CLASS_STATUS_VERIFIED | JVMTI_CLASS_STATUS_PREPARED;
}
if (is_initialized()) {
assert(is_linked(), "Class status is not consistent");
result |= JVMTI_CLASS_STATUS_INITIALIZED;
}
if (is_in_error_state()) {
result |= JVMTI_CLASS_STATUS_ERROR;
}
return result;
}
Method* InstanceKlass::method_at_itable(InstanceKlass* holder, int index, TRAPS) {
bool implements_interface; // initialized by method_at_itable_or_null
Method* m = method_at_itable_or_null(holder, index,
implements_interface); // out parameter
if (m != nullptr) {
assert(implements_interface, "sanity");
return m;
} else if (implements_interface) {
// Throw AbstractMethodError since corresponding itable slot is empty.
THROW_NULL(vmSymbols::java_lang_AbstractMethodError());
} else {
// If the interface isn't implemented by the receiver class,
// the VM should throw IncompatibleClassChangeError.
ResourceMark rm(THREAD);
stringStream ss;
bool same_module = (module() == holder->module());
ss.print("Receiver class %s does not implement "
"the interface %s defining the method to be called "
"(%s%s%s)",
external_name(), holder->external_name(),
(same_module) ? joint_in_module_of_loader(holder) : class_in_module_of_loader(),
(same_module) ? "" : "; ",
(same_module) ? "" : holder->class_in_module_of_loader());
THROW_MSG_NULL(vmSymbols::java_lang_IncompatibleClassChangeError(), ss.as_string());
}
}
Method* InstanceKlass::method_at_itable_or_null(InstanceKlass* holder, int index, bool& implements_interface) {
klassItable itable(this);
for (int i = 0; i < itable.size_offset_table(); i++) {
itableOffsetEntry* offset_entry = itable.offset_entry(i);
if (offset_entry->interface_klass() == holder) {
implements_interface = true;
itableMethodEntry* ime = offset_entry->first_method_entry(this);
Method* m = ime[index].method();
return m;
}
}
implements_interface = false;
return nullptr; // offset entry not found
}
int InstanceKlass::vtable_index_of_interface_method(Method* intf_method) {
assert(is_linked(), "required");
assert(intf_method->method_holder()->is_interface(), "not an interface method");
assert(is_subtype_of(intf_method->method_holder()), "interface not implemented");
int vtable_index = Method::invalid_vtable_index;
Symbol* name = intf_method->name();
Symbol* signature = intf_method->signature();
// First check in default method array
if (!intf_method->is_abstract() && default_methods() != nullptr) {
int index = find_method_index(default_methods(),
name, signature,
Klass::OverpassLookupMode::find,
Klass::StaticLookupMode::find,
Klass::PrivateLookupMode::find);
if (index >= 0) {
vtable_index = default_vtable_indices()->at(index);
}
}
if (vtable_index == Method::invalid_vtable_index) {
// get vtable_index for miranda methods
klassVtable vt = vtable();
vtable_index = vt.index_of_miranda(name, signature);
}
return vtable_index;
}
#if INCLUDE_JVMTI
// update default_methods for redefineclasses for methods that are
// not yet in the vtable due to concurrent subclass define and superinterface
// redefinition
// Note: those in the vtable, should have been updated via adjust_method_entries
void InstanceKlass::adjust_default_methods(bool* trace_name_printed) {
// search the default_methods for uses of either obsolete or EMCP methods
if (default_methods() != nullptr) {
for (int index = 0; index < default_methods()->length(); index ++) {
Method* old_method = default_methods()->at(index);
if (old_method == nullptr || !old_method->is_old()) {
continue; // skip uninteresting entries
}
assert(!old_method->is_deleted(), "default methods may not be deleted");
Method* new_method = old_method->get_new_method();
default_methods()->at_put(index, new_method);
if (log_is_enabled(Info, redefine, class, update)) {
ResourceMark rm;
if (!(*trace_name_printed)) {
log_info(redefine, class, update)
("adjust: klassname=%s default methods from name=%s",
external_name(), old_method->method_holder()->external_name());
*trace_name_printed = true;
}
log_debug(redefine, class, update, vtables)
("default method update: %s(%s) ",
new_method->name()->as_C_string(), new_method->signature()->as_C_string());
}
}
}
}
#endif // INCLUDE_JVMTI
// On-stack replacement stuff
void InstanceKlass::add_osr_nmethod(nmethod* n) {
assert_lock_strong(CompiledMethod_lock);
#ifndef PRODUCT
nmethod* prev = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), n->comp_level(), true);
assert(prev == nullptr || !prev->is_in_use() COMPILER2_PRESENT(|| StressRecompilation),
"redundant OSR recompilation detected. memory leak in CodeCache!");
#endif
// only one compilation can be active
assert(n->is_osr_method(), "wrong kind of nmethod");
n->set_osr_link(osr_nmethods_head());
set_osr_nmethods_head(n);
// Raise the highest osr level if necessary
n->method()->set_highest_osr_comp_level(MAX2(n->method()->highest_osr_comp_level(), n->comp_level()));
// Get rid of the osr methods for the same bci that have lower levels.
for (int l = CompLevel_limited_profile; l < n->comp_level(); l++) {
nmethod *inv = lookup_osr_nmethod(n->method(), n->osr_entry_bci(), l, true);
if (inv != nullptr && inv->is_in_use()) {
inv->make_not_entrant();
}
}
}
// Remove osr nmethod from the list. Return true if found and removed.
bool InstanceKlass::remove_osr_nmethod(nmethod* n) {
// This is a short non-blocking critical region, so the no safepoint check is ok.
MutexLocker ml(CompiledMethod_lock->owned_by_self() ? nullptr : CompiledMethod_lock
, Mutex::_no_safepoint_check_flag);
assert(n->is_osr_method(), "wrong kind of nmethod");
nmethod* last = nullptr;
nmethod* cur = osr_nmethods_head();
int max_level = CompLevel_none; // Find the max comp level excluding n
Method* m = n->method();
// Search for match
bool found = false;
while(cur != nullptr && cur != n) {
if (m == cur->method()) {
// Find max level before n
max_level = MAX2(max_level, cur->comp_level());
}
last = cur;
cur = cur->osr_link();
}
nmethod* next = nullptr;
if (cur == n) {
found = true;
next = cur->osr_link();
if (last == nullptr) {
// Remove first element
set_osr_nmethods_head(next);
} else {
last->set_osr_link(next);
}
}
n->set_osr_link(nullptr);
cur = next;
while (cur != nullptr) {
// Find max level after n
if (m == cur->method()) {
max_level = MAX2(max_level, cur->comp_level());
}
cur = cur->osr_link();
}
m->set_highest_osr_comp_level(max_level);
return found;
}
int InstanceKlass::mark_osr_nmethods(DeoptimizationScope* deopt_scope, const Method* m) {
MutexLocker ml(CompiledMethod_lock->owned_by_self() ? nullptr : CompiledMethod_lock,
Mutex::_no_safepoint_check_flag);
nmethod* osr = osr_nmethods_head();
int found = 0;
while (osr != nullptr) {
assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
if (osr->method() == m) {
deopt_scope->mark(osr);
found++;
}
osr = osr->osr_link();
}
return found;
}
nmethod* InstanceKlass::lookup_osr_nmethod(const Method* m, int bci, int comp_level, bool match_level) const {
MutexLocker ml(CompiledMethod_lock->owned_by_self() ? nullptr : CompiledMethod_lock,
Mutex::_no_safepoint_check_flag);
nmethod* osr = osr_nmethods_head();
nmethod* best = nullptr;
while (osr != nullptr) {
assert(osr->is_osr_method(), "wrong kind of nmethod found in chain");
// There can be a time when a c1 osr method exists but we are waiting
// for a c2 version. When c2 completes its osr nmethod we will trash
// the c1 version and only be able to find the c2 version. However
// while we overflow in the c1 code at back branches we don't want to
// try and switch to the same code as we are already running
if (osr->method() == m &&
(bci == InvocationEntryBci || osr->osr_entry_bci() == bci)) {
if (match_level) {
if (osr->comp_level() == comp_level) {
// Found a match - return it.
return osr;
}
} else {
if (best == nullptr || (osr->comp_level() > best->comp_level())) {
if (osr->comp_level() == CompilationPolicy::highest_compile_level()) {
// Found the best possible - return it.
return osr;
}
best = osr;
}
}
}
osr = osr->osr_link();
}
assert(match_level == false || best == nullptr, "shouldn't pick up anything if match_level is set");
if (best != nullptr && best->comp_level() >= comp_level) {
return best;
}
return nullptr;
}
// -----------------------------------------------------------------------------------------------------
// Printing
#define BULLET " - "
static const char* state_names[] = {
"allocated", "loaded", "being_linked", "linked", "being_initialized", "fully_initialized", "initialization_error"
};
static void print_vtable(intptr_t* start, int len, outputStream* st) {
for (int i = 0; i < len; i++) {
intptr_t e = start[i];
st->print("%d : " INTPTR_FORMAT, i, e);
if (MetaspaceObj::is_valid((Metadata*)e)) {
st->print(" ");
((Metadata*)e)->print_value_on(st);
}
st->cr();
}
}
static void print_vtable(vtableEntry* start, int len, outputStream* st) {
return print_vtable(reinterpret_cast<intptr_t*>(start), len, st);
}
const char* InstanceKlass::init_state_name() const {
return state_names[init_state()];
}
void InstanceKlass::print_on(outputStream* st) const {
assert(is_klass(), "must be klass");
Klass::print_on(st);
st->print(BULLET"instance size: %d", size_helper()); st->cr();
st->print(BULLET"klass size: %d", size()); st->cr();
st->print(BULLET"access: "); access_flags().print_on(st); st->cr();
st->print(BULLET"flags: "); _misc_flags.print_on(st); st->cr();
st->print(BULLET"state: "); st->print_cr("%s", init_state_name());
st->print(BULLET"name: "); name()->print_value_on(st); st->cr();
st->print(BULLET"super: "); Metadata::print_value_on_maybe_null(st, super()); st->cr();
st->print(BULLET"sub: ");
Klass* sub = subklass();
int n;
for (n = 0; sub != nullptr; n++, sub = sub->next_sibling()) {
if (n < MaxSubklassPrintSize) {
sub->print_value_on(st);
st->print(" ");
}
}
if (n >= MaxSubklassPrintSize) st->print("(" INTX_FORMAT " more klasses...)", n - MaxSubklassPrintSize);
st->cr();
if (is_interface()) {
st->print_cr(BULLET"nof implementors: %d", nof_implementors());
if (nof_implementors() == 1) {
st->print_cr(BULLET"implementor: ");
st->print(" ");
implementor()->print_value_on(st);
st->cr();
}
}
st->print(BULLET"arrays: "); Metadata::print_value_on_maybe_null(st, array_klasses()); st->cr();
st->print(BULLET"methods: "); methods()->print_value_on(st); st->cr();
if (Verbose || WizardMode) {
Array<Method*>* method_array = methods();
for (int i = 0; i < method_array->length(); i++) {
st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
}
}
st->print(BULLET"method ordering: "); method_ordering()->print_value_on(st); st->cr();
st->print(BULLET"default_methods: "); default_methods()->print_value_on(st); st->cr();
if (Verbose && default_methods() != nullptr) {
Array<Method*>* method_array = default_methods();
for (int i = 0; i < method_array->length(); i++) {
st->print("%d : ", i); method_array->at(i)->print_value(); st->cr();
}
}
if (default_vtable_indices() != nullptr) {
st->print(BULLET"default vtable indices: "); default_vtable_indices()->print_value_on(st); st->cr();
}
st->print(BULLET"local interfaces: "); local_interfaces()->print_value_on(st); st->cr();
st->print(BULLET"trans. interfaces: "); transitive_interfaces()->print_value_on(st); st->cr();
st->print(BULLET"constants: "); constants()->print_value_on(st); st->cr();
if (class_loader_data() != nullptr) {
st->print(BULLET"class loader data: ");
class_loader_data()->print_value_on(st);
st->cr();
}
if (source_file_name() != nullptr) {
st->print(BULLET"source file: ");
source_file_name()->print_value_on(st);
st->cr();
}
if (source_debug_extension() != nullptr) {
st->print(BULLET"source debug extension: ");
st->print("%s", source_debug_extension());
st->cr();
}
st->print(BULLET"class annotations: "); class_annotations()->print_value_on(st); st->cr();
st->print(BULLET"class type annotations: "); class_type_annotations()->print_value_on(st); st->cr();
st->print(BULLET"field annotations: "); fields_annotations()->print_value_on(st); st->cr();
st->print(BULLET"field type annotations: "); fields_type_annotations()->print_value_on(st); st->cr();
{
bool have_pv = false;
// previous versions are linked together through the InstanceKlass
for (InstanceKlass* pv_node = previous_versions();
pv_node != nullptr;
pv_node = pv_node->previous_versions()) {
if (!have_pv)
st->print(BULLET"previous version: ");
have_pv = true;
pv_node->constants()->print_value_on(st);
}
if (have_pv) st->cr();
}
if (generic_signature() != nullptr) {
st->print(BULLET"generic signature: ");
generic_signature()->print_value_on(st);
st->cr();
}
st->print(BULLET"inner classes: "); inner_classes()->print_value_on(st); st->cr();
st->print(BULLET"nest members: "); nest_members()->print_value_on(st); st->cr();
if (record_components() != nullptr) {
st->print(BULLET"record components: "); record_components()->print_value_on(st); st->cr();
}
st->print(BULLET"permitted subclasses: "); permitted_subclasses()->print_value_on(st); st->cr();
if (java_mirror() != nullptr) {
st->print(BULLET"java mirror: ");
java_mirror()->print_value_on(st);
st->cr();
} else {
st->print_cr(BULLET"java mirror: null");
}
st->print(BULLET"vtable length %d (start addr: " PTR_FORMAT ")", vtable_length(), p2i(start_of_vtable())); st->cr();
if (vtable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_vtable(), vtable_length(), st);
st->print(BULLET"itable length %d (start addr: " PTR_FORMAT ")", itable_length(), p2i(start_of_itable())); st->cr();
if (itable_length() > 0 && (Verbose || WizardMode)) print_vtable(start_of_itable(), itable_length(), st);
st->print_cr(BULLET"---- static fields (%d words):", static_field_size());
FieldPrinter print_static_field(st);
((InstanceKlass*)this)->do_local_static_fields(&print_static_field);
st->print_cr(BULLET"---- non-static fields (%d words):", nonstatic_field_size());
FieldPrinter print_nonstatic_field(st);
InstanceKlass* ik = const_cast<InstanceKlass*>(this);
ik->print_nonstatic_fields(&print_nonstatic_field);
st->print(BULLET"non-static oop maps: ");
OopMapBlock* map = start_of_nonstatic_oop_maps();
OopMapBlock* end_map = map + nonstatic_oop_map_count();
while (map < end_map) {
st->print("%d-%d ", map->offset(), map->offset() + heapOopSize*(map->count() - 1));
map++;
}
st->cr();
}
void InstanceKlass::print_value_on(outputStream* st) const {
assert(is_klass(), "must be klass");
if (Verbose || WizardMode) access_flags().print_on(st);
name()->print_value_on(st);
}
void FieldPrinter::do_field(fieldDescriptor* fd) {
_st->print(BULLET);
if (_obj == nullptr) {
fd->print_on(_st);
_st->cr();
} else {
fd->print_on_for(_st, _obj);
_st->cr();
}
}
void InstanceKlass::oop_print_on(oop obj, outputStream* st) {
Klass::oop_print_on(obj, st);
if (this == vmClasses::String_klass()) {
typeArrayOop value = java_lang_String::value(obj);
juint length = java_lang_String::length(obj);
if (value != nullptr &&
value->is_typeArray() &&
length <= (juint) value->length()) {
st->print(BULLET"string: ");
java_lang_String::print(obj, st);
st->cr();
}
}
st->print_cr(BULLET"---- fields (total size " SIZE_FORMAT " words):", oop_size(obj));
FieldPrinter print_field(st, obj);
print_nonstatic_fields(&print_field);
if (this == vmClasses::Class_klass()) {
st->print(BULLET"signature: ");
java_lang_Class::print_signature(obj, st);
st->cr();
Klass* real_klass = java_lang_Class::as_Klass(obj);
if (real_klass != nullptr && real_klass->is_instance_klass()) {
st->print_cr(BULLET"---- static fields (%d):", java_lang_Class::static_oop_field_count(obj));
InstanceKlass::cast(real_klass)->do_local_static_fields(&print_field);
}
} else if (this == vmClasses::MethodType_klass()) {
st->print(BULLET"signature: ");
java_lang_invoke_MethodType::print_signature(obj, st);
st->cr();
}
}
#ifndef PRODUCT
bool InstanceKlass::verify_itable_index(int i) {
int method_count = klassItable::method_count_for_interface(this);
assert(i >= 0 && i < method_count, "index out of bounds");
return true;
}
#endif //PRODUCT
void InstanceKlass::oop_print_value_on(oop obj, outputStream* st) {
st->print("a ");
name()->print_value_on(st);
obj->print_address_on(st);
if (this == vmClasses::String_klass()
&& java_lang_String::value(obj) != nullptr) {
ResourceMark rm;
int len = java_lang_String::length(obj);
int plen = (len < 24 ? len : 12);
char* str = java_lang_String::as_utf8_string(obj, 0, plen);
st->print(" = \"%s\"", str);
if (len > plen)
st->print("...[%d]", len);
} else if (this == vmClasses::Class_klass()) {
Klass* k = java_lang_Class::as_Klass(obj);
st->print(" = ");
if (k != nullptr) {
k->print_value_on(st);
} else {
const char* tname = type2name(java_lang_Class::primitive_type(obj));
st->print("%s", tname ? tname : "type?");
}
} else if (this == vmClasses::MethodType_klass()) {
st->print(" = ");
java_lang_invoke_MethodType::print_signature(obj, st);
} else if (java_lang_boxing_object::is_instance(obj)) {
st->print(" = ");
java_lang_boxing_object::print(obj, st);
} else if (this == vmClasses::LambdaForm_klass()) {
oop vmentry = java_lang_invoke_LambdaForm::vmentry(obj);
if (vmentry != nullptr) {
st->print(" => ");
vmentry->print_value_on(st);
}
} else if (this == vmClasses::MemberName_klass()) {
Metadata* vmtarget = java_lang_invoke_MemberName::vmtarget(obj);
if (vmtarget != nullptr) {
st->print(" = ");
vmtarget->print_value_on(st);
} else {
oop clazz = java_lang_invoke_MemberName::clazz(obj);
oop name = java_lang_invoke_MemberName::name(obj);
if (clazz != nullptr) {
clazz->print_value_on(st);
} else {
st->print("null");
}
st->print(".");
if (name != nullptr) {
name->print_value_on(st);
} else {
st->print("null");
}
}
}
}
const char* InstanceKlass::internal_name() const {
return external_name();
}
void InstanceKlass::print_class_load_logging(ClassLoaderData* loader_data,
const ModuleEntry* module_entry,
const ClassFileStream* cfs) const {
if (ClassListWriter::is_enabled()) {
ClassListWriter::write(this, cfs);
}
if (!log_is_enabled(Info, class, load)) {
return;
}
ResourceMark rm;
LogMessage(class, load) msg;
stringStream info_stream;
// Name and class hierarchy info
info_stream.print("%s", external_name());
// Source
if (cfs != nullptr) {
if (cfs->source() != nullptr) {
const char* module_name = (module_entry->name() == nullptr) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
if (module_name != nullptr) {
// When the boot loader created the stream, it didn't know the module name
// yet. Let's format it now.
if (cfs->from_boot_loader_modules_image()) {
info_stream.print(" source: jrt:/%s", module_name);
} else {
info_stream.print(" source: %s", cfs->source());
}
} else {
info_stream.print(" source: %s", cfs->source());
}
} else if (loader_data == ClassLoaderData::the_null_class_loader_data()) {
Thread* current = Thread::current();
Klass* caller = current->is_Java_thread() ?
JavaThread::cast(current)->security_get_caller_class(1):
nullptr;
// caller can be null, for example, during a JVMTI VM_Init hook
if (caller != nullptr) {
info_stream.print(" source: instance of %s", caller->external_name());
} else {
// source is unknown
}
} else {
oop class_loader = loader_data->class_loader();
info_stream.print(" source: %s", class_loader->klass()->external_name());
}
} else {
assert(this->is_shared(), "must be");
if (MetaspaceShared::is_shared_dynamic((void*)this)) {
info_stream.print(" source: shared objects file (top)");
} else {
info_stream.print(" source: shared objects file");
}
}
msg.info("%s", info_stream.as_string());
if (log_is_enabled(Debug, class, load)) {
stringStream debug_stream;
// Class hierarchy info
debug_stream.print(" klass: " PTR_FORMAT " super: " PTR_FORMAT,
p2i(this), p2i(superklass()));
// Interfaces
if (local_interfaces() != nullptr && local_interfaces()->length() > 0) {
debug_stream.print(" interfaces:");
int length = local_interfaces()->length();
for (int i = 0; i < length; i++) {
debug_stream.print(" " PTR_FORMAT,
p2i(InstanceKlass::cast(local_interfaces()->at(i))));
}
}
// Class loader
debug_stream.print(" loader: [");
loader_data->print_value_on(&debug_stream);
debug_stream.print("]");
// Classfile checksum
if (cfs) {
debug_stream.print(" bytes: %d checksum: %08x",
cfs->length(),
ClassLoader::crc32(0, (const char*)cfs->buffer(),
cfs->length()));
}
msg.debug("%s", debug_stream.as_string());
}
}
// Verification
class VerifyFieldClosure: public BasicOopIterateClosure {
protected:
template <class T> void do_oop_work(T* p) {
oop obj = RawAccess<>::oop_load(p);
if (!oopDesc::is_oop_or_null(obj)) {
tty->print_cr("Failed: " PTR_FORMAT " -> " PTR_FORMAT, p2i(p), p2i(obj));
Universe::print_on(tty);
guarantee(false, "boom");
}
}
public:
virtual void do_oop(oop* p) { VerifyFieldClosure::do_oop_work(p); }
virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
};
void InstanceKlass::verify_on(outputStream* st) {
#ifndef PRODUCT
// Avoid redundant verifies, this really should be in product.
if (_verify_count == Universe::verify_count()) return;
_verify_count = Universe::verify_count();
#endif
// Verify Klass
Klass::verify_on(st);
// Verify that klass is present in ClassLoaderData
guarantee(class_loader_data()->contains_klass(this),
"this class isn't found in class loader data");
// Verify vtables
if (is_linked()) {
// $$$ This used to be done only for m/s collections. Doing it
// always seemed a valid generalization. (DLD -- 6/00)
vtable().verify(st);
}
// Verify first subklass
if (subklass() != nullptr) {
guarantee(subklass()->is_klass(), "should be klass");
}
// Verify siblings
Klass* super = this->super();
Klass* sib = next_sibling();
if (sib != nullptr) {
if (sib == this) {
fatal("subclass points to itself " PTR_FORMAT, p2i(sib));
}
guarantee(sib->is_klass(), "should be klass");
guarantee(sib->super() == super, "siblings should have same superklass");
}
// Verify local interfaces
if (local_interfaces()) {
Array<InstanceKlass*>* local_interfaces = this->local_interfaces();
for (int j = 0; j < local_interfaces->length(); j++) {
InstanceKlass* e = local_interfaces->at(j);
guarantee(e->is_klass() && e->is_interface(), "invalid local interface");
}
}
// Verify transitive interfaces
if (transitive_interfaces() != nullptr) {
Array<InstanceKlass*>* transitive_interfaces = this->transitive_interfaces();
for (int j = 0; j < transitive_interfaces->length(); j++) {
InstanceKlass* e = transitive_interfaces->at(j);
guarantee(e->is_klass() && e->is_interface(), "invalid transitive interface");
}
}
// Verify methods
if (methods() != nullptr) {
Array<Method*>* methods = this->methods();
for (int j = 0; j < methods->length(); j++) {
guarantee(methods->at(j)->is_method(), "non-method in methods array");
}
for (int j = 0; j < methods->length() - 1; j++) {
Method* m1 = methods->at(j);
Method* m2 = methods->at(j + 1);
guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
}
}
// Verify method ordering
if (method_ordering() != nullptr) {
Array<int>* method_ordering = this->method_ordering();
int length = method_ordering->length();
if (JvmtiExport::can_maintain_original_method_order() ||
((UseSharedSpaces || Arguments::is_dumping_archive()) && length != 0)) {
guarantee(length == methods()->length(), "invalid method ordering length");
jlong sum = 0;
for (int j = 0; j < length; j++) {
int original_index = method_ordering->at(j);
guarantee(original_index >= 0, "invalid method ordering index");
guarantee(original_index < length, "invalid method ordering index");
sum += original_index;
}
// Verify sum of indices 0,1,...,length-1
guarantee(sum == ((jlong)length*(length-1))/2, "invalid method ordering sum");
} else {
guarantee(length == 0, "invalid method ordering length");
}
}
// Verify default methods
if (default_methods() != nullptr) {
Array<Method*>* methods = this->default_methods();
for (int j = 0; j < methods->length(); j++) {
guarantee(methods->at(j)->is_method(), "non-method in methods array");
}
for (int j = 0; j < methods->length() - 1; j++) {
Method* m1 = methods->at(j);
Method* m2 = methods->at(j + 1);
guarantee(m1->name()->fast_compare(m2->name()) <= 0, "methods not sorted correctly");
}
}
// Verify JNI static field identifiers
if (jni_ids() != nullptr) {
jni_ids()->verify(this);
}
// Verify other fields
if (constants() != nullptr) {
guarantee(constants()->is_constantPool(), "should be constant pool");
}
}
void InstanceKlass::oop_verify_on(oop obj, outputStream* st) {
Klass::oop_verify_on(obj, st);
VerifyFieldClosure blk;
obj->oop_iterate(&blk);
}
// JNIid class for jfieldIDs only
// Note to reviewers:
// These JNI functions are just moved over to column 1 and not changed
// in the compressed oops workspace.
JNIid::JNIid(Klass* holder, int offset, JNIid* next) {
_holder = holder;
_offset = offset;
_next = next;
debug_only(_is_static_field_id = false;)
}
JNIid* JNIid::find(int offset) {
JNIid* current = this;
while (current != nullptr) {
if (current->offset() == offset) return current;
current = current->next();
}
return nullptr;
}
void JNIid::deallocate(JNIid* current) {
while (current != nullptr) {
JNIid* next = current->next();
delete current;
current = next;
}
}
void JNIid::verify(Klass* holder) {
int first_field_offset = InstanceMirrorKlass::offset_of_static_fields();
int end_field_offset;
end_field_offset = first_field_offset + (InstanceKlass::cast(holder)->static_field_size() * wordSize);
JNIid* current = this;
while (current != nullptr) {
guarantee(current->holder() == holder, "Invalid klass in JNIid");
#ifdef ASSERT
int o = current->offset();
if (current->is_static_field_id()) {
guarantee(o >= first_field_offset && o < end_field_offset, "Invalid static field offset in JNIid");
}
#endif
current = current->next();
}
}
void InstanceKlass::set_init_state(ClassState state) {
if (state > loaded) {
assert_lock_strong(_init_monitor);
}
#ifdef ASSERT
bool good_state = is_shared() ? (_init_state <= state)
: (_init_state < state);
bool link_failed = _init_state == being_linked && state == loaded;
assert(good_state || state == allocated || link_failed, "illegal state transition");
#endif
assert(_init_thread == nullptr, "should be cleared before state change");
Atomic::store(&_init_state, state);
}
#if INCLUDE_JVMTI
// RedefineClasses() support for previous versions
// Globally, there is at least one previous version of a class to walk
// during class unloading, which is saved because old methods in the class
// are still running. Otherwise the previous version list is cleaned up.
bool InstanceKlass::_should_clean_previous_versions = false;
// Returns true if there are previous versions of a class for class
// unloading only. Also resets the flag to false. purge_previous_version
// will set the flag to true if there are any left, i.e., if there's any
// work to do for next time. This is to avoid the expensive code cache
// walk in CLDG::clean_deallocate_lists().
bool InstanceKlass::should_clean_previous_versions_and_reset() {
bool ret = _should_clean_previous_versions;
log_trace(redefine, class, iklass, purge)("Class unloading: should_clean_previous_versions = %s",
ret ? "true" : "false");
_should_clean_previous_versions = false;
return ret;
}
// This nulls out jmethodIDs for all methods in 'klass'
// It needs to be called explicitly for all previous versions of a class because these may not be cleaned up
// during class unloading.
// We can not use the jmethodID cache associated with klass directly because the 'previous' versions
// do not have the jmethodID cache filled in. Instead, we need to lookup jmethodID for each method and this
// is expensive - O(n) for one jmethodID lookup. For all contained methods it is O(n^2).
// The reason for expensive jmethodID lookup for each method is that there is no direct link between method and jmethodID.
void InstanceKlass::clear_jmethod_ids(InstanceKlass* klass) {
Array<Method*>* method_refs = klass->methods();
for (int k = 0; k < method_refs->length(); k++) {
Method* method = method_refs->at(k);
if (method != nullptr && method->is_obsolete()) {
method->clear_jmethod_id();
}
}
}
// Purge previous versions before adding new previous versions of the class and
// during class unloading.
void InstanceKlass::purge_previous_version_list() {
assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
assert(has_been_redefined(), "Should only be called for main class");
// Quick exit.
if (previous_versions() == nullptr) {
return;
}
// This klass has previous versions so see what we can cleanup
// while it is safe to do so.
int deleted_count = 0; // leave debugging breadcrumbs
int live_count = 0;
ClassLoaderData* loader_data = class_loader_data();
assert(loader_data != nullptr, "should never be null");
ResourceMark rm;
log_trace(redefine, class, iklass, purge)("%s: previous versions", external_name());
// previous versions are linked together through the InstanceKlass
InstanceKlass* pv_node = previous_versions();
InstanceKlass* last = this;
int version = 0;
// check the previous versions list
for (; pv_node != nullptr; ) {
ConstantPool* pvcp = pv_node->constants();
assert(pvcp != nullptr, "cp ref was unexpectedly cleared");
if (!pvcp->on_stack()) {
// If the constant pool isn't on stack, none of the methods
// are executing. Unlink this previous_version.
// The previous version InstanceKlass is on the ClassLoaderData deallocate list
// so will be deallocated during the next phase of class unloading.
log_trace(redefine, class, iklass, purge)
("previous version " PTR_FORMAT " is dead.", p2i(pv_node));
// Unlink from previous version list.
assert(pv_node->class_loader_data() == loader_data, "wrong loader_data");
InstanceKlass* next = pv_node->previous_versions();
clear_jmethod_ids(pv_node); // jmethodID maintenance for the unloaded class
pv_node->link_previous_versions(nullptr); // point next to null
last->link_previous_versions(next);
// Delete this node directly. Nothing is referring to it and we don't
// want it to increase the counter for metadata to delete in CLDG.
MetadataFactory::free_metadata(loader_data, pv_node);
pv_node = next;
deleted_count++;
version++;
continue;
} else {
assert(pvcp->pool_holder() != nullptr, "Constant pool with no holder");
guarantee (!loader_data->is_unloading(), "unloaded classes can't be on the stack");
live_count++;
if (pvcp->is_shared()) {
// Shared previous versions can never be removed so no cleaning is needed.
log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is shared", p2i(pv_node));
} else {
// Previous version alive, set that clean is needed for next time.
_should_clean_previous_versions = true;
log_trace(redefine, class, iklass, purge)("previous version " PTR_FORMAT " is alive", p2i(pv_node));
}
}
// next previous version
last = pv_node;
pv_node = pv_node->previous_versions();
version++;
}
log_trace(redefine, class, iklass, purge)
("previous version stats: live=%d, deleted=%d", live_count, deleted_count);
}
void InstanceKlass::mark_newly_obsolete_methods(Array<Method*>* old_methods,
int emcp_method_count) {
int obsolete_method_count = old_methods->length() - emcp_method_count;
if (emcp_method_count != 0 && obsolete_method_count != 0 &&
_previous_versions != nullptr) {
// We have a mix of obsolete and EMCP methods so we have to
// clear out any matching EMCP method entries the hard way.
int local_count = 0;
for (int i = 0; i < old_methods->length(); i++) {
Method* old_method = old_methods->at(i);
if (old_method->is_obsolete()) {
// only obsolete methods are interesting
Symbol* m_name = old_method->name();
Symbol* m_signature = old_method->signature();
// previous versions are linked together through the InstanceKlass
int j = 0;
for (InstanceKlass* prev_version = _previous_versions;
prev_version != nullptr;
prev_version = prev_version->previous_versions(), j++) {
Array<Method*>* method_refs = prev_version->methods();
for (int k = 0; k < method_refs->length(); k++) {
Method* method = method_refs->at(k);
if (!method->is_obsolete() &&
method->name() == m_name &&
method->signature() == m_signature) {
// The current RedefineClasses() call has made all EMCP
// versions of this method obsolete so mark it as obsolete
log_trace(redefine, class, iklass, add)
("%s(%s): flush obsolete method @%d in version @%d",
m_name->as_C_string(), m_signature->as_C_string(), k, j);
method->set_is_obsolete();
break;
}
}
// The previous loop may not find a matching EMCP method, but
// that doesn't mean that we can optimize and not go any
// further back in the PreviousVersion generations. The EMCP
// method for this generation could have already been made obsolete,
// but there still may be an older EMCP method that has not
// been made obsolete.
}
if (++local_count >= obsolete_method_count) {
// no more obsolete methods so bail out now
break;
}
}
}
}
}
// Save the scratch_class as the previous version if any of the methods are running.
// The previous_versions are used to set breakpoints in EMCP methods and they are
// also used to clean MethodData links to redefined methods that are no longer running.
void InstanceKlass::add_previous_version(InstanceKlass* scratch_class,
int emcp_method_count) {
assert(Thread::current()->is_VM_thread(),
"only VMThread can add previous versions");
ResourceMark rm;
log_trace(redefine, class, iklass, add)
("adding previous version ref for %s, EMCP_cnt=%d", scratch_class->external_name(), emcp_method_count);
// Clean out old previous versions for this class
purge_previous_version_list();
// Mark newly obsolete methods in remaining previous versions. An EMCP method from
// a previous redefinition may be made obsolete by this redefinition.
Array<Method*>* old_methods = scratch_class->methods();
mark_newly_obsolete_methods(old_methods, emcp_method_count);
// If the constant pool for this previous version of the class
// is not marked as being on the stack, then none of the methods
// in this previous version of the class are on the stack so
// we don't need to add this as a previous version.
ConstantPool* cp_ref = scratch_class->constants();
if (!cp_ref->on_stack()) {
log_trace(redefine, class, iklass, add)("scratch class not added; no methods are running");
scratch_class->class_loader_data()->add_to_deallocate_list(scratch_class);
return;
}
// Add previous version if any methods are still running or if this is
// a shared class which should never be removed.
assert(scratch_class->previous_versions() == nullptr, "shouldn't have a previous version");
scratch_class->link_previous_versions(previous_versions());
link_previous_versions(scratch_class);
if (cp_ref->is_shared()) {
log_trace(redefine, class, iklass, add) ("scratch class added; class is shared");
} else {
// We only set clean_previous_versions flag for processing during class
// unloading for non-shared classes.
_should_clean_previous_versions = true;
log_trace(redefine, class, iklass, add) ("scratch class added; one of its methods is on_stack.");
}
} // end add_previous_version()
#endif // INCLUDE_JVMTI
Method* InstanceKlass::method_with_idnum(int idnum) {
Method* m = nullptr;
if (idnum < methods()->length()) {
m = methods()->at(idnum);
}
if (m == nullptr || m->method_idnum() != idnum) {
for (int index = 0; index < methods()->length(); ++index) {
m = methods()->at(index);
if (m->method_idnum() == idnum) {
return m;
}
}
// None found, return null for the caller to handle.
return nullptr;
}
return m;
}
Method* InstanceKlass::method_with_orig_idnum(int idnum) {
if (idnum >= methods()->length()) {
return nullptr;
}
Method* m = methods()->at(idnum);
if (m != nullptr && m->orig_method_idnum() == idnum) {
return m;
}
// Obsolete method idnum does not match the original idnum
for (int index = 0; index < methods()->length(); ++index) {
m = methods()->at(index);
if (m->orig_method_idnum() == idnum) {
return m;
}
}
// None found, return null for the caller to handle.
return nullptr;
}
Method* InstanceKlass::method_with_orig_idnum(int idnum, int version) {
InstanceKlass* holder = get_klass_version(version);
if (holder == nullptr) {
return nullptr; // The version of klass is gone, no method is found
}
Method* method = holder->method_with_orig_idnum(idnum);
return method;
}
#if INCLUDE_JVMTI
JvmtiCachedClassFileData* InstanceKlass::get_cached_class_file() {
return _cached_class_file;
}
jint InstanceKlass::get_cached_class_file_len() {
return VM_RedefineClasses::get_cached_class_file_len(_cached_class_file);
}
unsigned char * InstanceKlass::get_cached_class_file_bytes() {
return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
}
#endif
// Make a step iterating over the class hierarchy under the root class.
// Skips subclasses if requested.
void ClassHierarchyIterator::next() {
assert(_current != nullptr, "required");
if (_visit_subclasses && _current->subklass() != nullptr) {
_current = _current->subklass();
return; // visit next subclass
}
_visit_subclasses = true; // reset
while (_current->next_sibling() == nullptr && _current != _root) {
_current = _current->superklass(); // backtrack; no more sibling subclasses left
}
if (_current == _root) {
// Iteration is over (back at root after backtracking). Invalidate the iterator.
_current = nullptr;
return;
}
_current = _current->next_sibling();
return; // visit next sibling subclass
}