toolchains/bootclasspath.bzl - platform/external/bazelbuild-rules_java - Git at Google

 # Copyright 2024 The Bazel Authors. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 #    http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.

 """Rules for extracting a platform classpath from Java runtimes."""

 load("@bazel_skylib//rules:common_settings.bzl", "BuildSettingInfo")
 load("//java/common:java_common.bzl", "java_common")
 load(":utf8_environment.bzl", "Utf8EnvironmentInfo")

 visibility("private")

 # TODO: This provider and is only necessary since --java_{language,runtime}_version
 # are not available directly to Starlark.
 _JavaVersionsInfo = provider(
     "Exposes the --java_{language,runtime}_version value as extracted from a transition to a dependant.",
     fields = {
         "java_language_version": "The value of --java_language_version",
         "java_runtime_version": "The value of --java_runtime_version",
     },
 )

 def _language_version_bootstrap_runtime(ctx):
     providers = [
         _JavaVersionsInfo(
             java_language_version = ctx.attr.java_language_version[BuildSettingInfo].value,
             java_runtime_version = ctx.attr.java_runtime_version[BuildSettingInfo].value,
         ),
     ]

     bootstrap_runtime = ctx.toolchains["@bazel_tools//tools/jdk:bootstrap_runtime_toolchain_type"]
     if bootstrap_runtime:
         providers.append(bootstrap_runtime.java_runtime)

     return providers

 language_version_bootstrap_runtime = rule(
     implementation = _language_version_bootstrap_runtime,
     attrs = {
         "java_language_version": attr.label(
             providers = [BuildSettingInfo],
         ),
         "java_runtime_version": attr.label(
             providers = [BuildSettingInfo],
         ),
     },
     toolchains = [
         config_common.toolchain_type("@bazel_tools//tools/jdk:bootstrap_runtime_toolchain_type", mandatory = False),
     ],
 )

 def _get_bootstrap_runtime_version(*, java_language_version, java_runtime_version):
     """Returns the runtime version to use for bootstrapping the given language version.

     If the runtime version is not versioned, e.g. "local_jdk", it is used as is.
     Otherwise, the language version replaces the numeric part of the runtime version, e.g.,
     "remotejdk_17" becomes "remotejdk_8".
     """
     prefix, separator, version = java_runtime_version.rpartition("_")
     if version and version.isdigit():
         new_version = java_language_version
     else:
         # The runtime version is not versioned, e.g. "local_jdk". Use it as is.
         new_version = version

     return prefix + separator + new_version

 def _bootclasspath_transition_impl(settings, _):
     java_language_version = settings["//command_line_option:java_language_version"]
     java_runtime_version = settings["//command_line_option:java_runtime_version"]

     return {
         "//command_line_option:java_runtime_version": _get_bootstrap_runtime_version(
             java_language_version = java_language_version,
             java_runtime_version = java_runtime_version,
         ),
         "//toolchains:java_language_version": java_language_version,
         "//toolchains:java_runtime_version": java_runtime_version,
     }

 _bootclasspath_transition = transition(
     implementation = _bootclasspath_transition_impl,
     inputs = [
         "//command_line_option:java_language_version",
         "//command_line_option:java_runtime_version",
     ],
     outputs = [
         "//command_line_option:java_runtime_version",
         "//toolchains:java_language_version",
         "//toolchains:java_runtime_version",
     ],
 )

 _JAVA_BOOTSTRAP_RUNTIME_TOOLCHAIN_TYPE = Label("@bazel_tools//tools/jdk:bootstrap_runtime_toolchain_type")

 # Opt the Java bootstrap actions into path mapping:
 # https://github.com/bazelbuild/bazel/commit/a239ea84832f18ee8706682145e9595e71b39680
 _SUPPORTS_PATH_MAPPING = {"supports-path-mapping": "1"}

 def _java_home(java_executable):
     return java_executable.dirname[:-len("/bin")]

 def _bootclasspath_impl(ctx):
     exec_javabase = ctx.attr.java_runtime_alias[java_common.JavaRuntimeInfo]
     env = ctx.attr._utf8_environment[Utf8EnvironmentInfo].environment

     class_dir = ctx.actions.declare_directory("%s_classes" % ctx.label.name)

     args = ctx.actions.args()
     args.add("-source")
     args.add("8")
     args.add("-target")
     args.add("8")
     args.add("-Xlint:-options")
     args.add("-J-XX:-UsePerfData")
     args.add("-d")
     args.add_all([class_dir], expand_directories = False)
     args.add(ctx.file.src)

     ctx.actions.run(
         executable = "%s/bin/javac" % exec_javabase.java_home,
         mnemonic = "JavaToolchainCompileClasses",
         inputs = [ctx.file.src] + ctx.files.java_runtime_alias,
         outputs = [class_dir],
         arguments = [args],
         env = env,
         execution_requirements = _SUPPORTS_PATH_MAPPING,
     )

     bootclasspath = ctx.outputs.output_jar

     args = ctx.actions.args()
     args.add("-XX:+IgnoreUnrecognizedVMOptions")
     args.add("-XX:-UsePerfData")
     args.add("--add-exports=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED")
     args.add("--add-exports=jdk.compiler/com.sun.tools.javac.platform=ALL-UNNAMED")
     args.add("--add-exports=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED")
     args.add_all("-cp", [class_dir], expand_directories = False)
     args.add("DumpPlatformClassPath")
     args.add(bootclasspath)

     if ctx.attr.language_version_bootstrap_runtime:
         # The attribute is subject to a split transition.
         language_version_bootstrap_runtime = ctx.attr.language_version_bootstrap_runtime[0]
         if java_common.JavaRuntimeInfo in language_version_bootstrap_runtime:
             any_javabase = language_version_bootstrap_runtime[java_common.JavaRuntimeInfo]
         else:
             java_versions_info = language_version_bootstrap_runtime[_JavaVersionsInfo]
             bootstrap_runtime_version = _get_bootstrap_runtime_version(
                 java_language_version = java_versions_info.java_language_version,
                 java_runtime_version = java_versions_info.java_runtime_version,
             )
             is_exec = "-exec" in ctx.bin_dir.path
             tool_prefix = "tool_" if is_exec else ""
             fail("""
 No Java runtime found to extract the bootclasspath from for --{tool_prefix}java_language_version={language_version} and --{tool_prefix}java_runtime_version={runtime_version}.
 You can:

     * register a Java runtime with name "{bootstrap_runtime_version}" to provide the bootclasspath or
     * set --java_language_version to the Java version of an available runtime.

 Rerun with --toolchain_resolution_debug='@bazel_tools//tools/jdk:bootstrap_runtime_toolchain_type' to see more details about toolchain resolution.
 """.format(
                 language_version = java_versions_info.java_language_version,
                 runtime_version = java_versions_info.java_runtime_version,
                 bootstrap_runtime_version = bootstrap_runtime_version,
                 tool_prefix = tool_prefix,
             ))
     else:
         any_javabase = ctx.toolchains[_JAVA_BOOTSTRAP_RUNTIME_TOOLCHAIN_TYPE].java_runtime
     any_javabase_files = any_javabase.files.to_list()

     # If possible, add the Java executable to the command line as a File so that it can be path
     # mapped.
     java_executable = [f for f in any_javabase_files if f.path == any_javabase.java_executable_exec_path]
     if len(java_executable) == 1:
         args.add_all(java_executable, map_each = _java_home)
     else:
         args.add(any_javabase.java_home)

     system_files = ("release", "modules", "jrt-fs.jar")
     system = [f for f in any_javabase_files if f.basename in system_files]
     if len(system) != len(system_files):
         system = None

     inputs = depset([class_dir] + ctx.files.java_runtime_alias, transitive = [any_javabase.files])
     ctx.actions.run(
         executable = str(exec_javabase.java_executable_exec_path),
         mnemonic = "JavaToolchainCompileBootClasspath",
         inputs = inputs,
         outputs = [bootclasspath],
         arguments = [args],
         env = env,
         execution_requirements = _SUPPORTS_PATH_MAPPING,
     )
     return [
         DefaultInfo(files = depset([bootclasspath])),
         java_common.BootClassPathInfo(
             bootclasspath = [bootclasspath],
             system = system,
         ),
         OutputGroupInfo(jar = [bootclasspath]),
     ]

 _bootclasspath = rule(
     implementation = _bootclasspath_impl,
     attrs = {
         "java_runtime_alias": attr.label(
             cfg = "exec",
             providers = [java_common.JavaRuntimeInfo],
         ),
         "language_version_bootstrap_runtime": attr.label(
             cfg = _bootclasspath_transition,
         ),
         "output_jar": attr.output(mandatory = True),
         "src": attr.label(
             cfg = "exec",
             allow_single_file = True,
         ),
         "_allowlist_function_transition": attr.label(
             default = "@bazel_tools//tools/allowlists/function_transition_allowlist",
         ),
         "_utf8_environment": attr.label(
             default = ":utf8_environment",
             cfg = "exec",
         ),
     },
     toolchains = [_JAVA_BOOTSTRAP_RUNTIME_TOOLCHAIN_TYPE],
 )

 def bootclasspath(name, **kwargs):
     _bootclasspath(
         name = name,
         output_jar = name + ".jar",
         **kwargs
     )
	# Copyright 2024 The Bazel Authors. All rights reserved.
	#
	# Licensed under the Apache License, Version 2.0 (the "License");
	# you may not use this file except in compliance with the License.
	# You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#
	# Unless required by applicable law or agreed to in writing, software
	# distributed under the License is distributed on an "AS IS" BASIS,
	# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	# See the License for the specific language governing permissions and
	# limitations under the License.

	"""Rules for extracting a platform classpath from Java runtimes."""

	load("@bazel_skylib//rules:common_settings.bzl", "BuildSettingInfo")
	load("//java/common:java_common.bzl", "java_common")
	load(":utf8_environment.bzl", "Utf8EnvironmentInfo")

	visibility("private")

	# TODO: This provider and is only necessary since --java_{language,runtime}_version
	# are not available directly to Starlark.
	_JavaVersionsInfo = provider(
	"Exposes the --java_{language,runtime}_version value as extracted from a transition to a dependant.",
	fields = {
	"java_language_version": "The value of --java_language_version",
	"java_runtime_version": "The value of --java_runtime_version",
	},
	)

	def _language_version_bootstrap_runtime(ctx):
	providers = [
	_JavaVersionsInfo(
	java_language_version = ctx.attr.java_language_version[BuildSettingInfo].value,
	java_runtime_version = ctx.attr.java_runtime_version[BuildSettingInfo].value,
	),
	]

	bootstrap_runtime = ctx.toolchains["@bazel_tools//tools/jdk:bootstrap_runtime_toolchain_type"]
	if bootstrap_runtime:
	providers.append(bootstrap_runtime.java_runtime)

	return providers

	language_version_bootstrap_runtime = rule(
	implementation = _language_version_bootstrap_runtime,
	attrs = {
	"java_language_version": attr.label(
	providers = [BuildSettingInfo],
	),
	"java_runtime_version": attr.label(
	providers = [BuildSettingInfo],
	),
	},
	toolchains = [
	config_common.toolchain_type("@bazel_tools//tools/jdk:bootstrap_runtime_toolchain_type", mandatory = False),
	],
	)

	def _get_bootstrap_runtime_version(*, java_language_version, java_runtime_version):
	"""Returns the runtime version to use for bootstrapping the given language version.

	If the runtime version is not versioned, e.g. "local_jdk", it is used as is.
	Otherwise, the language version replaces the numeric part of the runtime version, e.g.,
	"remotejdk_17" becomes "remotejdk_8".
	"""
	prefix, separator, version = java_runtime_version.rpartition("_")
	if version and version.isdigit():
	new_version = java_language_version
	else:
	# The runtime version is not versioned, e.g. "local_jdk". Use it as is.
	new_version = version

	return prefix + separator + new_version

	def _bootclasspath_transition_impl(settings, _):
	java_language_version = settings["//command_line_option:java_language_version"]
	java_runtime_version = settings["//command_line_option:java_runtime_version"]

	return {
	"//command_line_option:java_runtime_version": _get_bootstrap_runtime_version(
	java_language_version = java_language_version,
	java_runtime_version = java_runtime_version,
	),
	"//toolchains:java_language_version": java_language_version,
	"//toolchains:java_runtime_version": java_runtime_version,
	}

	_bootclasspath_transition = transition(
	implementation = _bootclasspath_transition_impl,
	inputs = [
	"//command_line_option:java_language_version",
	"//command_line_option:java_runtime_version",
	],
	outputs = [
	"//command_line_option:java_runtime_version",
	"//toolchains:java_language_version",
	"//toolchains:java_runtime_version",
	],
	)

	_JAVA_BOOTSTRAP_RUNTIME_TOOLCHAIN_TYPE = Label("@bazel_tools//tools/jdk:bootstrap_runtime_toolchain_type")

	# Opt the Java bootstrap actions into path mapping:
	# https://github.com/bazelbuild/bazel/commit/a239ea84832f18ee8706682145e9595e71b39680
	_SUPPORTS_PATH_MAPPING = {"supports-path-mapping": "1"}

	def _java_home(java_executable):
	return java_executable.dirname[:-len("/bin")]

	def _bootclasspath_impl(ctx):
	exec_javabase = ctx.attr.java_runtime_alias[java_common.JavaRuntimeInfo]
	env = ctx.attr._utf8_environment[Utf8EnvironmentInfo].environment

	class_dir = ctx.actions.declare_directory("%s_classes" % ctx.label.name)

	args = ctx.actions.args()
	args.add("-source")
	args.add("8")
	args.add("-target")
	args.add("8")
	args.add("-Xlint:-options")
	args.add("-J-XX:-UsePerfData")
	args.add("-d")
	args.add_all([class_dir], expand_directories = False)
	args.add(ctx.file.src)

	ctx.actions.run(
	executable = "%s/bin/javac" % exec_javabase.java_home,
	mnemonic = "JavaToolchainCompileClasses",
	inputs = [ctx.file.src] + ctx.files.java_runtime_alias,
	outputs = [class_dir],
	arguments = [args],
	env = env,
	execution_requirements = _SUPPORTS_PATH_MAPPING,
	)

	bootclasspath = ctx.outputs.output_jar

	args = ctx.actions.args()
	args.add("-XX:+IgnoreUnrecognizedVMOptions")
	args.add("-XX:-UsePerfData")
	args.add("--add-exports=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED")
	args.add("--add-exports=jdk.compiler/com.sun.tools.javac.platform=ALL-UNNAMED")
	args.add("--add-exports=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED")
	args.add_all("-cp", [class_dir], expand_directories = False)
	args.add("DumpPlatformClassPath")
	args.add(bootclasspath)

	if ctx.attr.language_version_bootstrap_runtime:
	# The attribute is subject to a split transition.
	language_version_bootstrap_runtime = ctx.attr.language_version_bootstrap_runtime[0]
	if java_common.JavaRuntimeInfo in language_version_bootstrap_runtime:
	any_javabase = language_version_bootstrap_runtime[java_common.JavaRuntimeInfo]
	else:
	java_versions_info = language_version_bootstrap_runtime[_JavaVersionsInfo]
	bootstrap_runtime_version = _get_bootstrap_runtime_version(
	java_language_version = java_versions_info.java_language_version,
	java_runtime_version = java_versions_info.java_runtime_version,
	)
	is_exec = "-exec" in ctx.bin_dir.path
	tool_prefix = "tool_" if is_exec else ""
	fail("""
	No Java runtime found to extract the bootclasspath from for --{tool_prefix}java_language_version={language_version} and --{tool_prefix}java_runtime_version={runtime_version}.
	You can:

	* register a Java runtime with name "{bootstrap_runtime_version}" to provide the bootclasspath or
	* set --java_language_version to the Java version of an available runtime.

	Rerun with --toolchain_resolution_debug='@bazel_tools//tools/jdk:bootstrap_runtime_toolchain_type' to see more details about toolchain resolution.
	""".format(
	language_version = java_versions_info.java_language_version,
	runtime_version = java_versions_info.java_runtime_version,
	bootstrap_runtime_version = bootstrap_runtime_version,
	tool_prefix = tool_prefix,
	))
	else:
	any_javabase = ctx.toolchains[_JAVA_BOOTSTRAP_RUNTIME_TOOLCHAIN_TYPE].java_runtime
	any_javabase_files = any_javabase.files.to_list()

	# If possible, add the Java executable to the command line as a File so that it can be path
	# mapped.
	java_executable = [f for f in any_javabase_files if f.path == any_javabase.java_executable_exec_path]
	if len(java_executable) == 1:
	args.add_all(java_executable, map_each = _java_home)
	else:
	args.add(any_javabase.java_home)

	system_files = ("release", "modules", "jrt-fs.jar")
	system = [f for f in any_javabase_files if f.basename in system_files]
	if len(system) != len(system_files):
	system = None

	inputs = depset([class_dir] + ctx.files.java_runtime_alias, transitive = [any_javabase.files])
	ctx.actions.run(
	executable = str(exec_javabase.java_executable_exec_path),
	mnemonic = "JavaToolchainCompileBootClasspath",
	inputs = inputs,
	outputs = [bootclasspath],
	arguments = [args],
	env = env,
	execution_requirements = _SUPPORTS_PATH_MAPPING,
	)
	return [
	DefaultInfo(files = depset([bootclasspath])),
	java_common.BootClassPathInfo(
	bootclasspath = [bootclasspath],
	system = system,
	),
	OutputGroupInfo(jar = [bootclasspath]),
	]

	_bootclasspath = rule(
	implementation = _bootclasspath_impl,
	attrs = {
	"java_runtime_alias": attr.label(
	cfg = "exec",
	providers = [java_common.JavaRuntimeInfo],
	),
	"language_version_bootstrap_runtime": attr.label(
	cfg = _bootclasspath_transition,
	),
	"output_jar": attr.output(mandatory = True),
	"src": attr.label(
	cfg = "exec",
	allow_single_file = True,
	),
	"_allowlist_function_transition": attr.label(
	default = "@bazel_tools//tools/allowlists/function_transition_allowlist",
	),
	"_utf8_environment": attr.label(
	default = ":utf8_environment",
	cfg = "exec",
	),
	},
	toolchains = [_JAVA_BOOTSTRAP_RUNTIME_TOOLCHAIN_TYPE],
	)

	def bootclasspath(name, **kwargs):
	_bootclasspath(
	name = name,
	output_jar = name + ".jar",
	**kwargs
	)