src/hotspot/share/oops/klass.inline.hpp

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * version 2 for more details (a copy is included in the LICENSE file that
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 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_OOPS_KLASS_INLINE_HPP
#define SHARE_OOPS_KLASS_INLINE_HPP

#include "oops/klass.hpp"

#include "classfile/classLoaderData.inline.hpp"
#include "oops/klassVtable.hpp"
#include "oops/markWord.hpp"

// This loads and keeps the klass's loader alive.
inline oop Klass::klass_holder() const {
  return class_loader_data()->holder();
}

inline bool Klass::is_non_strong_hidden() const {
  return access_flags().is_hidden_class() &&
         class_loader_data()->has_class_mirror_holder();
}

// Iff the class loader (or mirror for non-strong hidden classes) is alive the
// Klass is considered alive. This is safe to call before the CLD is marked as
// unloading, and hence during concurrent class unloading.
// This returns false if the Klass is unloaded, or about to be unloaded because the holder of
// the CLD is no longer strongly reachable.
// The return value of this function may change from true to false after a safepoint. So the caller
// of this function must ensure that a safepoint doesn't happen while interpreting the return value.
inline bool Klass::is_loader_alive() const {
  return class_loader_data()->is_alive();
}

inline oop Klass::java_mirror() const {
  return _java_mirror.resolve();
}

inline oop Klass::java_mirror_no_keepalive() const {
  return _java_mirror.peek();
}

inline klassVtable Klass::vtable() const {
  return klassVtable(const_cast<Klass*>(this), start_of_vtable(), vtable_length() / vtableEntry::size());
}

inline oop Klass::class_loader() const {
  return class_loader_data()->class_loader();
}

inline vtableEntry* Klass::start_of_vtable() const {
  return (vtableEntry*) ((address)this + in_bytes(vtable_start_offset()));
}

inline ByteSize Klass::vtable_start_offset() {
  return in_ByteSize(InstanceKlass::header_size() * wordSize);
}

#endif // SHARE_OOPS_KLASS_INLINE_HPP