java/bazel/rules/bazel_java_binary.bzl - rules_java - Git at Google

 # Copyright 2022 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.
 """Bazel java_binary rule"""

 load("@bazel_skylib//lib:paths.bzl", "paths")
 load("@rules_cc//cc:find_cc_toolchain.bzl", "use_cc_toolchain")
 load("//java/common:java_info.bzl", "JavaInfo")
 load("//java/common:java_semantics.bzl", "semantics")
 load(
     "//java/common/rules:android_lint.bzl",
     "android_lint_subrule",
 )
 load("//java/common/rules:java_binary.bzl", "BASIC_JAVA_BINARY_ATTRIBUTES")
 load("//java/common/rules:rule_util.bzl", "merge_attrs")
 load("//java/common/rules/impl:java_binary_deploy_jar.bzl", "create_deploy_archives")
 load("//java/common/rules/impl:java_binary_impl.bzl", "basic_java_binary")
 load("//java/common/rules/impl:java_helper.bzl", "helper")

 def _bazel_java_binary_impl(ctx):
     return bazel_base_binary_impl(ctx, is_test_rule_class = False) + helper.executable_providers(ctx)

 def bazel_base_binary_impl(ctx, is_test_rule_class):
     """Common implementation for binaries and tests

     Args:
         ctx: (RuleContext)
         is_test_rule_class: (bool)

     Returns:
         [Provider]
     """
     deps = _collect_all_targets_as_deps(ctx, classpath_type = "compile_only")
     runtime_deps = _collect_all_targets_as_deps(ctx)

     main_class = _check_and_get_main_class(ctx)
     coverage_main_class = main_class
     coverage_config = helper.get_coverage_config(ctx, _get_coverage_runner(ctx))
     if coverage_config:
         main_class = coverage_config.main_class

     launcher_info = _get_launcher_info(ctx)

     executable = _get_executable(ctx)

     feature_config = helper.get_feature_config(ctx)
     if feature_config:
         strip_as_default = helper.should_strip_as_default(ctx, feature_config)
     else:
         # No C++ toolchain available.
         strip_as_default = False

     providers, default_info, jvm_flags = basic_java_binary(
         ctx,
         deps,
         runtime_deps,
         ctx.files.resources,
         main_class,
         coverage_main_class,
         coverage_config,
         launcher_info,
         executable,
         strip_as_default,
         is_test_rule_class = is_test_rule_class,
     )

     if ctx.attr.use_testrunner:
         if semantics.find_java_runtime_toolchain(ctx).version >= 17:
             jvm_flags.append("-Djava.security.manager=allow")
         test_class = ctx.attr.test_class if hasattr(ctx.attr, "test_class") else ""
         if test_class == "":
             test_class = helper.primary_class(ctx)
         if test_class == None:
             fail("cannot determine test class. You might want to rename the " +
                  " rule or add a 'test_class' attribute.")
         jvm_flags.extend([
             "-ea",
             "-Dbazel.test_suite=" + helper.shell_escape(test_class),
         ])

     java_attrs = providers["InternalDeployJarInfo"].java_attrs

     if executable:
         _create_stub(ctx, java_attrs, launcher_info.launcher, executable, jvm_flags, main_class, coverage_main_class)

     runfiles = default_info.runfiles

     if executable:
         runtime_toolchain = semantics.find_java_runtime_toolchain(ctx)
         runfiles = runfiles.merge(ctx.runfiles(transitive_files = runtime_toolchain.files))

     test_support = helper.get_test_support(ctx)
     if test_support:
         runfiles = runfiles.merge(test_support[DefaultInfo].default_runfiles)

     providers["DefaultInfo"] = DefaultInfo(
         files = default_info.files,
         runfiles = runfiles,
         executable = default_info.executable,
     )

     info = providers.pop("InternalDeployJarInfo")
     create_deploy_archives(
         ctx,
         info.java_attrs,
         launcher_info,
         main_class,
         coverage_main_class,
         info.strip_as_default,
         add_exports = info.add_exports,
         add_opens = info.add_opens,
     )

     return providers.values()

 def _get_coverage_runner(ctx):
     if ctx.configuration.coverage_enabled and ctx.attr.create_executable:
         toolchain = semantics.find_java_toolchain(ctx)
         runner = toolchain.jacocorunner
         if not runner:
             fail("jacocorunner not set in java_toolchain: %s" % toolchain.label)
         runner_jar = runner.executable

         # wrap the jar in JavaInfo so we can add it to deps for java_common.compile()
         return JavaInfo(output_jar = runner_jar, compile_jar = runner_jar)

     return None

 def _collect_all_targets_as_deps(ctx, classpath_type = "all"):
     deps = helper.collect_all_targets_as_deps(ctx, classpath_type = classpath_type)

     if classpath_type == "compile_only" and ctx.fragments.java.enforce_explicit_java_test_deps():
         return deps

     test_support = helper.get_test_support(ctx)
     if test_support:
         deps.append(test_support)
     return deps

 def _check_and_get_main_class(ctx):
     create_executable = ctx.attr.create_executable
     main_class = _get_main_class(ctx)

     if not create_executable and main_class:
         fail("main class must not be specified when executable is not created")
     if create_executable and not main_class:
         if not ctx.attr.srcs:
             fail("need at least one of 'main_class' or Java source files")
         main_class = helper.primary_class(ctx)
         if main_class == None:
             fail("main_class was not provided and cannot be inferred: " +
                  "source path doesn't include a known root (java, javatests, src, testsrc)")

     return _get_main_class(ctx)

 def _get_main_class(ctx):
     if not ctx.attr.create_executable:
         return None

     main_class = _get_main_class_from_rule(ctx)

     if main_class == "":
         main_class = helper.primary_class(ctx)
     return main_class

 def _get_main_class_from_rule(ctx):
     main_class = ctx.attr.main_class
     if main_class:
         return main_class
     if ctx.attr.use_testrunner:
         return "com.google.testing.junit.runner.BazelTestRunner"
     return main_class

 def _get_launcher_info(ctx):
     launcher = helper.launcher_artifact_for_target(ctx)
     return struct(
         launcher = launcher,
         unstripped_launcher = launcher,
         runfiles = [],
         runtime_jars = [],
         jvm_flags = [],
         classpath_resources = [],
     )

 def _get_executable(ctx):
     if not ctx.attr.create_executable:
         return None
     executable_name = ctx.label.name
     if helper.is_target_platform_windows(ctx):
         executable_name = executable_name + ".exe"

     return ctx.actions.declare_file(executable_name)

 def _create_stub(ctx, java_attrs, launcher, executable, jvm_flags, main_class, coverage_main_class):
     java_runtime_toolchain = semantics.find_java_runtime_toolchain(ctx)
     java_executable = helper.get_java_executable(ctx, java_runtime_toolchain, launcher)
     workspace_name = ctx.workspace_name
     workspace_prefix = workspace_name + ("/" if workspace_name else "")
     runfiles_enabled = helper.runfiles_enabled(ctx)
     coverage_enabled = ctx.configuration.coverage_enabled

     test_support = helper.get_test_support(ctx)
     test_support_jars = test_support[JavaInfo].transitive_runtime_jars if test_support else depset()
     classpath = depset(
         transitive = [
             java_attrs.runtime_classpath,
             test_support_jars if ctx.fragments.java.enforce_explicit_java_test_deps() else depset(),
         ],
     )

     if helper.is_target_platform_windows(ctx):
         jvm_flags_for_launcher = []
         for flag in jvm_flags:
             jvm_flags_for_launcher.extend(ctx.tokenize(flag))
         return _create_windows_exe_launcher(ctx, java_executable, classpath, main_class, jvm_flags_for_launcher, runfiles_enabled, executable)

     if runfiles_enabled:
         prefix = "" if helper.is_absolute_target_platform_path(ctx, java_executable) else "${JAVA_RUNFILES}/"
         java_bin = "JAVABIN=${JAVABIN:-" + prefix + java_executable + "}"
     else:
         java_bin = "JAVABIN=${JAVABIN:-$(rlocation " + java_executable + ")}"

     td = ctx.actions.template_dict()
     td.add_joined(
         "%classpath%",
         classpath,
         map_each = lambda file: _format_classpath_entry(runfiles_enabled, workspace_prefix, file),
         join_with = ctx.configuration.host_path_separator,
         format_joined = "\"%s\"",
         allow_closure = True,
     )

     ctx.actions.expand_template(
         template = ctx.file._stub_template,
         output = executable,
         substitutions = {
             "%runfiles_manifest_only%": "" if runfiles_enabled else "1",
             "%workspace_prefix%": workspace_prefix,
             "%javabin%": java_bin,
             "%needs_runfiles%": "0" if helper.is_absolute_target_platform_path(ctx, java_runtime_toolchain.java_executable_exec_path) else "1",
             "%set_jacoco_metadata%": "",
             "%set_jacoco_main_class%": "export JACOCO_MAIN_CLASS=" + coverage_main_class if coverage_enabled else "",
             "%set_jacoco_java_runfiles_root%": "export JACOCO_JAVA_RUNFILES_ROOT=${JAVA_RUNFILES}/" + workspace_prefix if coverage_enabled else "",
             "%java_start_class%": helper.shell_escape(main_class),
             "%jvm_flags%": " ".join(jvm_flags),
         },
         computed_substitutions = td,
         is_executable = True,
     )
     return executable

 def _format_classpath_entry(runfiles_enabled, workspace_prefix, file):
     if runfiles_enabled:
         return "${RUNPATH}" + file.short_path

     return "$(rlocation " + paths.normalize(workspace_prefix + file.short_path) + ")"

 def _create_windows_exe_launcher(ctx, java_executable, classpath, main_class, jvm_flags_for_launcher, runfiles_enabled, executable):
     launch_info = ctx.actions.args().use_param_file("%s", use_always = True).set_param_file_format("multiline")
     launch_info.add("binary_type=Java")
     launch_info.add(ctx.workspace_name, format = "workspace_name=%s")
     launch_info.add("1" if runfiles_enabled else "0", format = "symlink_runfiles_enabled=%s")
     launch_info.add(java_executable, format = "java_bin_path=%s")
     launch_info.add(main_class, format = "java_start_class=%s")
     launch_info.add_joined(classpath, map_each = _short_path, join_with = ";", format_joined = "classpath=%s", omit_if_empty = False)
     launch_info.add_joined(jvm_flags_for_launcher, join_with = "\t", format_joined = "jvm_flags=%s", omit_if_empty = False)
     launch_info.add(semantics.find_java_runtime_toolchain(ctx).java_home_runfiles_path, format = "jar_bin_path=%s/bin/jar.exe")

     # TODO(b/295221112): Change to use the "launcher" attribute (only windows use a fixed _launcher attribute)
     launcher_artifact = ctx.executable._launcher
     ctx.actions.run(
         executable = ctx.executable._windows_launcher_maker,
         inputs = [launcher_artifact],
         outputs = [executable],
         arguments = [launcher_artifact.path, launch_info, executable.path],
         use_default_shell_env = True,
     )
     return executable

 def _short_path(file):
     return file.short_path

 def _compute_test_support(use_testrunner):
     return Label(semantics.JAVA_TEST_RUNNER_LABEL) if use_testrunner else None

 def make_binary_rule(implementation, *, doc, attrs, executable = False, test = False, initializer = None):
     return rule(
         implementation = implementation,
         initializer = initializer,
         doc = doc,
         attrs = attrs,
         executable = executable,
         test = test,
         fragments = ["cpp", "java"],
         provides = [JavaInfo],
         toolchains = [semantics.JAVA_TOOLCHAIN] + use_cc_toolchain() + (
             [semantics.JAVA_RUNTIME_TOOLCHAIN] if executable or test else []
         ),
         # TODO(hvd): replace with filegroups?
         outputs = {
             "classjar": "%{name}.jar",
             "sourcejar": "%{name}-src.jar",
             "deploysrcjar": "%{name}_deploy-src.jar",
             "deployjar": "%{name}_deploy.jar",
             "unstrippeddeployjar": "%{name}_deploy.jar.unstripped",
         },
         exec_groups = {
             "cpp_link": exec_group(toolchains = use_cc_toolchain()),
         },
         subrules = [android_lint_subrule],
     )

 BASE_BINARY_ATTRS = merge_attrs(
     BASIC_JAVA_BINARY_ATTRIBUTES,
     {
         "resource_strip_prefix": attr.string(
             doc = """
 The path prefix to strip from Java resources.
 <p>
 If specified, this path prefix is stripped from every file in the <code>resources</code>
 attribute. It is an error for a resource file not to be under this directory. If not
 specified (the default), the path of resource file is determined according to the same
 logic as the Java package of source files. For example, a source file at
 <code>stuff/java/foo/bar/a.txt</code> will be located at <code>foo/bar/a.txt</code>.
 </p>
             """,
         ),
         "_test_support": attr.label(default = _compute_test_support),
         "_launcher": attr.label(
             cfg = "exec",
             executable = True,
             default = "@bazel_tools//tools/launcher:launcher",
         ),
         "_windows_launcher_maker": attr.label(
             default = "@bazel_tools//tools/launcher:launcher_maker",
             cfg = "exec",
             executable = True,
         ),
     },
 )

 def make_java_binary(executable):
     return make_binary_rule(
         _bazel_java_binary_impl,
         doc = """
 <p>
   Builds a Java archive ("jar file"), plus a wrapper shell script with the same name as the rule.
   The wrapper shell script uses a classpath that includes, among other things, a jar file for each
   library on which the binary depends. When running the wrapper shell script, any nonempty
   <code>JAVABIN</code> environment variable will take precedence over the version specified via
   Bazel's <code>--java_runtime_version</code> flag.
 </p>
 <p>
   The wrapper script accepts several unique flags. Refer to
   <code>//src/main/java/com/google/devtools/build/lib/bazel/rules/java/java_stub_template.txt</code>
   for a list of configurable flags and environment variables accepted by the wrapper.
 </p>

 <h4 id="java_binary_implicit_outputs">Implicit output targets</h4>
 <ul>
   <li><code><var>name</var>.jar</code>: A Java archive, containing the class files and other
     resources corresponding to the binary's direct dependencies.</li>
   <li><code><var>name</var>-src.jar</code>: An archive containing the sources ("source
     jar").</li>
   <li><code><var>name</var>_deploy.jar</code>: A Java archive suitable for deployment (only
     built if explicitly requested).
     <p>
       Building the <code>&lt;<var>name</var>&gt;_deploy.jar</code> target for your rule
       creates a self-contained jar file with a manifest that allows it to be run with the
       <code>java -jar</code> command or with the wrapper script's <code>--singlejar</code>
       option. Using the wrapper script is preferred to <code>java -jar</code> because it
       also passes the <a href="#java_binary-jvm_flags">JVM flags</a> and the options
       to load native libraries.
     </p>
     <p>
       The deploy jar contains all the classes that would be found by a classloader that
       searched the classpath from the binary's wrapper script from beginning to end. It also
       contains the native libraries needed for dependencies. These are automatically loaded
       into the JVM at runtime.
     </p>
     <p>If your target specifies a <a href="#java_binary.launcher">launcher</a>
       attribute, then instead of being a normal JAR file, the _deploy.jar will be a
       native binary. This will contain the launcher plus any native (C++) dependencies of
       your rule, all linked into a static binary. The actual jar file's bytes will be
       appended to that native binary, creating a single binary blob containing both the
       executable and the Java code. You can execute the resulting jar file directly
       like you would execute any native binary.</p>
   </li>
   <li><code><var>name</var>_deploy-src.jar</code>: An archive containing the sources
     collected from the transitive closure of the target. These will match the classes in the
     <code>deploy.jar</code> except where jars have no matching source jar.</li>
 </ul>

 <p>
 It is good practice to use the name of the source file that is the main entry point of the
 application (minus the extension). For example, if your entry point is called
 <code>Main.java</code>, then your name could be <code>Main</code>.
 </p>

 <p>
   A <code>deps</code> attribute is not allowed in a <code>java_binary</code> rule without
   <a href="#java_binary-srcs"><code>srcs</code></a>; such a rule requires a
   <a href="#java_binary-main_class"><code>main_class</code></a> provided by
   <a href="#java_binary-runtime_deps"><code>runtime_deps</code></a>.
 </p>

 <p>The following code snippet illustrates a common mistake:</p>

 <pre class="code">
 <code class="lang-starlark">
 java_binary(
     name = "DontDoThis",
     srcs = [
         <var>...</var>,
         <code class="deprecated">"GeneratedJavaFile.java"</code>,  # a generated .java file
     ],
     deps = [<code class="deprecated">":generating_rule",</code>],  # rule that generates that file
 )
 </code>
 </pre>

 <p>Do this instead:</p>

 <pre class="code">
 <code class="lang-starlark">
 java_binary(
     name = "DoThisInstead",
     srcs = [
         <var>...</var>,
         ":generating_rule",
     ],
 )
 </code>
 </pre>
         """,
         attrs = merge_attrs(
             BASE_BINARY_ATTRS,
             ({} if executable else {
                 "args": attr.string_list(),
                 "output_licenses": attr.string_list(),
             }),
         ),
         executable = executable,
     )

 java_binary = make_java_binary(executable = True)
	# Copyright 2022 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.
	"""Bazel java_binary rule"""

	load("@bazel_skylib//lib:paths.bzl", "paths")
	load("@rules_cc//cc:find_cc_toolchain.bzl", "use_cc_toolchain")
	load("//java/common:java_info.bzl", "JavaInfo")
	load("//java/common:java_semantics.bzl", "semantics")
	load(
	"//java/common/rules:android_lint.bzl",
	"android_lint_subrule",
	)
	load("//java/common/rules:java_binary.bzl", "BASIC_JAVA_BINARY_ATTRIBUTES")
	load("//java/common/rules:rule_util.bzl", "merge_attrs")
	load("//java/common/rules/impl:java_binary_deploy_jar.bzl", "create_deploy_archives")
	load("//java/common/rules/impl:java_binary_impl.bzl", "basic_java_binary")
	load("//java/common/rules/impl:java_helper.bzl", "helper")

	def _bazel_java_binary_impl(ctx):
	return bazel_base_binary_impl(ctx, is_test_rule_class = False) + helper.executable_providers(ctx)

	def bazel_base_binary_impl(ctx, is_test_rule_class):
	"""Common implementation for binaries and tests

	Args:
	ctx: (RuleContext)
	is_test_rule_class: (bool)

	Returns:
	[Provider]
	"""
	deps = _collect_all_targets_as_deps(ctx, classpath_type = "compile_only")
	runtime_deps = _collect_all_targets_as_deps(ctx)

	main_class = _check_and_get_main_class(ctx)
	coverage_main_class = main_class
	coverage_config = helper.get_coverage_config(ctx, _get_coverage_runner(ctx))
	if coverage_config:
	main_class = coverage_config.main_class

	launcher_info = _get_launcher_info(ctx)

	executable = _get_executable(ctx)

	feature_config = helper.get_feature_config(ctx)
	if feature_config:
	strip_as_default = helper.should_strip_as_default(ctx, feature_config)
	else:
	# No C++ toolchain available.
	strip_as_default = False

	providers, default_info, jvm_flags = basic_java_binary(
	ctx,
	deps,
	runtime_deps,
	ctx.files.resources,
	main_class,
	coverage_main_class,
	coverage_config,
	launcher_info,
	executable,
	strip_as_default,
	is_test_rule_class = is_test_rule_class,
	)

	if ctx.attr.use_testrunner:
	if semantics.find_java_runtime_toolchain(ctx).version >= 17:
	jvm_flags.append("-Djava.security.manager=allow")
	test_class = ctx.attr.test_class if hasattr(ctx.attr, "test_class") else ""
	if test_class == "":
	test_class = helper.primary_class(ctx)
	if test_class == None:
	fail("cannot determine test class. You might want to rename the " +
	" rule or add a 'test_class' attribute.")
	jvm_flags.extend([
	"-ea",
	"-Dbazel.test_suite=" + helper.shell_escape(test_class),
	])

	java_attrs = providers["InternalDeployJarInfo"].java_attrs

	if executable:
	_create_stub(ctx, java_attrs, launcher_info.launcher, executable, jvm_flags, main_class, coverage_main_class)

	runfiles = default_info.runfiles

	if executable:
	runtime_toolchain = semantics.find_java_runtime_toolchain(ctx)
	runfiles = runfiles.merge(ctx.runfiles(transitive_files = runtime_toolchain.files))

	test_support = helper.get_test_support(ctx)
	if test_support:
	runfiles = runfiles.merge(test_support[DefaultInfo].default_runfiles)

	providers["DefaultInfo"] = DefaultInfo(
	files = default_info.files,
	runfiles = runfiles,
	executable = default_info.executable,
	)

	info = providers.pop("InternalDeployJarInfo")
	create_deploy_archives(
	ctx,
	info.java_attrs,
	launcher_info,
	main_class,
	coverage_main_class,
	info.strip_as_default,
	add_exports = info.add_exports,
	add_opens = info.add_opens,
	)

	return providers.values()

	def _get_coverage_runner(ctx):
	if ctx.configuration.coverage_enabled and ctx.attr.create_executable:
	toolchain = semantics.find_java_toolchain(ctx)
	runner = toolchain.jacocorunner
	if not runner:
	fail("jacocorunner not set in java_toolchain: %s" % toolchain.label)
	runner_jar = runner.executable

	# wrap the jar in JavaInfo so we can add it to deps for java_common.compile()
	return JavaInfo(output_jar = runner_jar, compile_jar = runner_jar)

	return None

	def _collect_all_targets_as_deps(ctx, classpath_type = "all"):
	deps = helper.collect_all_targets_as_deps(ctx, classpath_type = classpath_type)

	if classpath_type == "compile_only" and ctx.fragments.java.enforce_explicit_java_test_deps():
	return deps

	test_support = helper.get_test_support(ctx)
	if test_support:
	deps.append(test_support)
	return deps

	def _check_and_get_main_class(ctx):
	create_executable = ctx.attr.create_executable
	main_class = _get_main_class(ctx)

	if not create_executable and main_class:
	fail("main class must not be specified when executable is not created")
	if create_executable and not main_class:
	if not ctx.attr.srcs:
	fail("need at least one of 'main_class' or Java source files")
	main_class = helper.primary_class(ctx)
	if main_class == None:
	fail("main_class was not provided and cannot be inferred: " +
	"source path doesn't include a known root (java, javatests, src, testsrc)")

	return _get_main_class(ctx)

	def _get_main_class(ctx):
	if not ctx.attr.create_executable:
	return None

	main_class = _get_main_class_from_rule(ctx)

	if main_class == "":
	main_class = helper.primary_class(ctx)
	return main_class

	def _get_main_class_from_rule(ctx):
	main_class = ctx.attr.main_class
	if main_class:
	return main_class
	if ctx.attr.use_testrunner:
	return "com.google.testing.junit.runner.BazelTestRunner"
	return main_class

	def _get_launcher_info(ctx):
	launcher = helper.launcher_artifact_for_target(ctx)
	return struct(
	launcher = launcher,
	unstripped_launcher = launcher,
	runfiles = [],
	runtime_jars = [],
	jvm_flags = [],
	classpath_resources = [],
	)

	def _get_executable(ctx):
	if not ctx.attr.create_executable:
	return None
	executable_name = ctx.label.name
	if helper.is_target_platform_windows(ctx):
	executable_name = executable_name + ".exe"

	return ctx.actions.declare_file(executable_name)

	def _create_stub(ctx, java_attrs, launcher, executable, jvm_flags, main_class, coverage_main_class):
	java_runtime_toolchain = semantics.find_java_runtime_toolchain(ctx)
	java_executable = helper.get_java_executable(ctx, java_runtime_toolchain, launcher)
	workspace_name = ctx.workspace_name
	workspace_prefix = workspace_name + ("/" if workspace_name else "")
	runfiles_enabled = helper.runfiles_enabled(ctx)
	coverage_enabled = ctx.configuration.coverage_enabled

	test_support = helper.get_test_support(ctx)
	test_support_jars = test_support[JavaInfo].transitive_runtime_jars if test_support else depset()
	classpath = depset(
	transitive = [
	java_attrs.runtime_classpath,
	test_support_jars if ctx.fragments.java.enforce_explicit_java_test_deps() else depset(),
	],
	)

	if helper.is_target_platform_windows(ctx):
	jvm_flags_for_launcher = []
	for flag in jvm_flags:
	jvm_flags_for_launcher.extend(ctx.tokenize(flag))
	return _create_windows_exe_launcher(ctx, java_executable, classpath, main_class, jvm_flags_for_launcher, runfiles_enabled, executable)

	if runfiles_enabled:
	prefix = "" if helper.is_absolute_target_platform_path(ctx, java_executable) else "${JAVA_RUNFILES}/"
	java_bin = "JAVABIN=${JAVABIN:-" + prefix + java_executable + "}"
	else:
	java_bin = "JAVABIN=${JAVABIN:-$(rlocation " + java_executable + ")}"

	td = ctx.actions.template_dict()
	td.add_joined(
	"%classpath%",
	classpath,
	map_each = lambda file: _format_classpath_entry(runfiles_enabled, workspace_prefix, file),
	join_with = ctx.configuration.host_path_separator,
	format_joined = "\"%s\"",
	allow_closure = True,
	)

	ctx.actions.expand_template(
	template = ctx.file._stub_template,
	output = executable,
	substitutions = {
	"%runfiles_manifest_only%": "" if runfiles_enabled else "1",
	"%workspace_prefix%": workspace_prefix,
	"%javabin%": java_bin,
	"%needs_runfiles%": "0" if helper.is_absolute_target_platform_path(ctx, java_runtime_toolchain.java_executable_exec_path) else "1",
	"%set_jacoco_metadata%": "",
	"%set_jacoco_main_class%": "export JACOCO_MAIN_CLASS=" + coverage_main_class if coverage_enabled else "",
	"%set_jacoco_java_runfiles_root%": "export JACOCO_JAVA_RUNFILES_ROOT=${JAVA_RUNFILES}/" + workspace_prefix if coverage_enabled else "",
	"%java_start_class%": helper.shell_escape(main_class),
	"%jvm_flags%": " ".join(jvm_flags),
	},
	computed_substitutions = td,
	is_executable = True,
	)
	return executable

	def _format_classpath_entry(runfiles_enabled, workspace_prefix, file):
	if runfiles_enabled:
	return "${RUNPATH}" + file.short_path

	return "$(rlocation " + paths.normalize(workspace_prefix + file.short_path) + ")"

	def _create_windows_exe_launcher(ctx, java_executable, classpath, main_class, jvm_flags_for_launcher, runfiles_enabled, executable):
	launch_info = ctx.actions.args().use_param_file("%s", use_always = True).set_param_file_format("multiline")
	launch_info.add("binary_type=Java")
	launch_info.add(ctx.workspace_name, format = "workspace_name=%s")
	launch_info.add("1" if runfiles_enabled else "0", format = "symlink_runfiles_enabled=%s")
	launch_info.add(java_executable, format = "java_bin_path=%s")
	launch_info.add(main_class, format = "java_start_class=%s")
	launch_info.add_joined(classpath, map_each = _short_path, join_with = ";", format_joined = "classpath=%s", omit_if_empty = False)
	launch_info.add_joined(jvm_flags_for_launcher, join_with = "\t", format_joined = "jvm_flags=%s", omit_if_empty = False)
	launch_info.add(semantics.find_java_runtime_toolchain(ctx).java_home_runfiles_path, format = "jar_bin_path=%s/bin/jar.exe")

	# TODO(b/295221112): Change to use the "launcher" attribute (only windows use a fixed _launcher attribute)
	launcher_artifact = ctx.executable._launcher
	ctx.actions.run(
	executable = ctx.executable._windows_launcher_maker,
	inputs = [launcher_artifact],
	outputs = [executable],
	arguments = [launcher_artifact.path, launch_info, executable.path],
	use_default_shell_env = True,
	)
	return executable

	def _short_path(file):
	return file.short_path

	def _compute_test_support(use_testrunner):
	return Label(semantics.JAVA_TEST_RUNNER_LABEL) if use_testrunner else None

	def make_binary_rule(implementation, *, doc, attrs, executable = False, test = False, initializer = None):
	return rule(
	implementation = implementation,
	initializer = initializer,
	doc = doc,
	attrs = attrs,
	executable = executable,
	test = test,
	fragments = ["cpp", "java"],
	provides = [JavaInfo],
	toolchains = [semantics.JAVA_TOOLCHAIN] + use_cc_toolchain() + (
	[semantics.JAVA_RUNTIME_TOOLCHAIN] if executable or test else []
	),
	# TODO(hvd): replace with filegroups?
	outputs = {
	"classjar": "%{name}.jar",
	"sourcejar": "%{name}-src.jar",
	"deploysrcjar": "%{name}_deploy-src.jar",
	"deployjar": "%{name}_deploy.jar",
	"unstrippeddeployjar": "%{name}_deploy.jar.unstripped",
	},
	exec_groups = {
	"cpp_link": exec_group(toolchains = use_cc_toolchain()),
	},
	subrules = [android_lint_subrule],
	)

	BASE_BINARY_ATTRS = merge_attrs(
	BASIC_JAVA_BINARY_ATTRIBUTES,
	{
	"resource_strip_prefix": attr.string(
	doc = """
	The path prefix to strip from Java resources.
	<p>
	If specified, this path prefix is stripped from every file in the <code>resources</code>
	attribute. It is an error for a resource file not to be under this directory. If not
	specified (the default), the path of resource file is determined according to the same
	logic as the Java package of source files. For example, a source file at
	<code>stuff/java/foo/bar/a.txt</code> will be located at <code>foo/bar/a.txt</code>.
	</p>
	""",
	),
	"_test_support": attr.label(default = _compute_test_support),
	"_launcher": attr.label(
	cfg = "exec",
	executable = True,
	default = "@bazel_tools//tools/launcher:launcher",
	),
	"_windows_launcher_maker": attr.label(
	default = "@bazel_tools//tools/launcher:launcher_maker",
	cfg = "exec",
	executable = True,
	),
	},
	)

	def make_java_binary(executable):
	return make_binary_rule(
	_bazel_java_binary_impl,
	doc = """
	<p>
	Builds a Java archive ("jar file"), plus a wrapper shell script with the same name as the rule.
	The wrapper shell script uses a classpath that includes, among other things, a jar file for each
	library on which the binary depends. When running the wrapper shell script, any nonempty
	<code>JAVABIN</code> environment variable will take precedence over the version specified via
	Bazel's <code>--java_runtime_version</code> flag.
	</p>
	<p>
	The wrapper script accepts several unique flags. Refer to
	<code>//src/main/java/com/google/devtools/build/lib/bazel/rules/java/java_stub_template.txt</code>
	for a list of configurable flags and environment variables accepted by the wrapper.
	</p>

	<h4 id="java_binary_implicit_outputs">Implicit output targets</h4>
	<ul>
	<li><code><var>name</var>.jar</code>: A Java archive, containing the class files and other
	resources corresponding to the binary's direct dependencies.</li>
	<li><code><var>name</var>-src.jar</code>: An archive containing the sources ("source
	jar").</li>
	<li><code><var>name</var>_deploy.jar</code>: A Java archive suitable for deployment (only
	built if explicitly requested).
	<p>
	Building the <code><<var>name</var>>_deploy.jar</code> target for your rule
	creates a self-contained jar file with a manifest that allows it to be run with the
	<code>java -jar</code> command or with the wrapper script's <code>--singlejar</code>
	option. Using the wrapper script is preferred to <code>java -jar</code> because it
	also passes the <a href="#java_binary-jvm_flags">JVM flags</a> and the options
	to load native libraries.
	</p>
	<p>
	The deploy jar contains all the classes that would be found by a classloader that
	searched the classpath from the binary's wrapper script from beginning to end. It also
	contains the native libraries needed for dependencies. These are automatically loaded
	into the JVM at runtime.
	</p>
	<p>If your target specifies a <a href="#java_binary.launcher">launcher</a>
	attribute, then instead of being a normal JAR file, the _deploy.jar will be a
	native binary. This will contain the launcher plus any native (C++) dependencies of
	your rule, all linked into a static binary. The actual jar file's bytes will be
	appended to that native binary, creating a single binary blob containing both the
	executable and the Java code. You can execute the resulting jar file directly
	like you would execute any native binary.</p>
	</li>
	<li><code><var>name</var>_deploy-src.jar</code>: An archive containing the sources
	collected from the transitive closure of the target. These will match the classes in the
	<code>deploy.jar</code> except where jars have no matching source jar.</li>
	</ul>

	<p>
	It is good practice to use the name of the source file that is the main entry point of the
	application (minus the extension). For example, if your entry point is called
	<code>Main.java</code>, then your name could be <code>Main</code>.
	</p>

	<p>
	A <code>deps</code> attribute is not allowed in a <code>java_binary</code> rule without
	<a href="#java_binary-srcs"><code>srcs</code></a>; such a rule requires a
	<a href="#java_binary-main_class"><code>main_class</code></a> provided by
	<a href="#java_binary-runtime_deps"><code>runtime_deps</code></a>.
	</p>

	<p>The following code snippet illustrates a common mistake:</p>

	<pre class="code">
	<code class="lang-starlark">
	java_binary(
	name = "DontDoThis",
	srcs = [
	<var>...</var>,
	<code class="deprecated">"GeneratedJavaFile.java"</code>, # a generated .java file
	],
	deps = [<code class="deprecated">":generating_rule",</code>], # rule that generates that file
	)
	</code>
	</pre>

	<p>Do this instead:</p>

	<pre class="code">
	<code class="lang-starlark">
	java_binary(
	name = "DoThisInstead",
	srcs = [
	<var>...</var>,
	":generating_rule",
	],
	)
	</code>
	</pre>
	""",
	attrs = merge_attrs(
	BASE_BINARY_ATTRS,
	({} if executable else {
	"args": attr.string_list(),
	"output_licenses": attr.string_list(),
	}),
	),
	executable = executable,
	)

	java_binary = make_java_binary(executable = True)