java/builder.go - platform/build/soong - Git at Google

 // Copyright 2015 Google Inc. 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.

 package java

 // This file generates the final rules for compiling all Java.  All properties related to
 // compiling should have been translated into javaBuilderFlags or another argument to the Transform*
 // functions.

 import (
 	"path/filepath"
 	"strconv"
 	"strings"

 	"github.com/google/blueprint"

 	"android/soong/android"
 	"android/soong/java/config"
 )

 var (
 	pctx = android.NewPackageContext("android/soong/java")

 	// Compiling java is not conducive to proper dependency tracking.  The path-matches-class-name
 	// requirement leads to unpredictable generated source file names, and a single .java file
 	// will get compiled into multiple .class files if it contains inner classes.  To work around
 	// this, all java rules write into separate directories and then are combined into a .jar file
 	// (if the rule produces .class files) or a .srcjar file (if the rule produces .java files).
 	// .srcjar files are unzipped into a temporary directory when compiled with javac.
 	javac = pctx.AndroidGomaStaticRule("javac",
 		blueprint.RuleParams{
 			Command: `rm -rf "$outDir" "$annoDir" "$srcJarDir" && mkdir -p "$outDir" "$annoDir" "$srcJarDir" && ` +
 				`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
 				`${config.SoongJavacWrapper} ${config.JavacWrapper}${config.JavacCmd} ${config.JavacHeapFlags} ${config.CommonJdkFlags} ` +
 				`$javacFlags $bootClasspath $classpath ` +
 				`-source $javaVersion -target $javaVersion ` +
 				`-d $outDir -s $annoDir @$out.rsp @$srcJarDir/list && ` +
 				`${config.SoongZipCmd} -jar -o $out -C $outDir -D $outDir`,
 			CommandDeps: []string{
 				"${config.JavacCmd}",
 				"${config.SoongZipCmd}",
 				"${config.ZipSyncCmd}",
 			},
 			CommandOrderOnly: []string{"${config.SoongJavacWrapper}"},
 			Rspfile:          "$out.rsp",
 			RspfileContent:   "$in",
 		},
 		"javacFlags", "bootClasspath", "classpath", "srcJars", "srcJarDir",
 		"outDir", "annoDir", "javaVersion")

 	kotlinc = pctx.AndroidGomaStaticRule("kotlinc",
 		blueprint.RuleParams{
 			Command: `rm -rf "$outDir" "$srcJarDir" && mkdir -p "$outDir" "$srcJarDir" && ` +
 				`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
 				`${config.GenKotlinBuildFileCmd} $classpath $outDir $out.rsp $srcJarDir/list > $outDir/kotlinc-build.xml &&` +
 				`${config.KotlincCmd} $kotlincFlags ` +
 				`-jvm-target $kotlinJvmTarget -Xbuild-file=$outDir/kotlinc-build.xml && ` +
 				`${config.SoongZipCmd} -jar -o $out -C $outDir -D $outDir`,
 			CommandDeps: []string{
 				"${config.KotlincCmd}",
 				"${config.KotlinCompilerJar}",
 				"${config.GenKotlinBuildFileCmd}",
 				"${config.SoongZipCmd}",
 				"${config.ZipSyncCmd}",
 			},
 			Rspfile:        "$out.rsp",
 			RspfileContent: `$in`,
 		},
 		"kotlincFlags", "classpath", "srcJars", "srcJarDir", "outDir", "kotlinJvmTarget")

 	errorprone = pctx.AndroidStaticRule("errorprone",
 		blueprint.RuleParams{
 			Command: `rm -rf "$outDir" "$annoDir" "$srcJarDir" && mkdir -p "$outDir" "$annoDir" "$srcJarDir" && ` +
 				`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
 				`${config.SoongJavacWrapper} ${config.ErrorProneCmd} ` +
 				`$javacFlags $bootClasspath $classpath ` +
 				`-source $javaVersion -target $javaVersion ` +
 				`-d $outDir -s $annoDir @$out.rsp @$srcJarDir/list && ` +
 				`${config.SoongZipCmd} -jar -o $out -C $outDir -D $outDir`,
 			CommandDeps: []string{
 				"${config.JavaCmd}",
 				"${config.ErrorProneJavacJar}",
 				"${config.ErrorProneJar}",
 				"${config.SoongZipCmd}",
 				"${config.ZipSyncCmd}",
 			},
 			CommandOrderOnly: []string{"${config.SoongJavacWrapper}"},
 			Rspfile:          "$out.rsp",
 			RspfileContent:   "$in",
 		},
 		"javacFlags", "bootClasspath", "classpath", "srcJars", "srcJarDir",
 		"outDir", "annoDir", "javaVersion")

 	turbine = pctx.AndroidStaticRule("turbine",
 		blueprint.RuleParams{
 			Command: `rm -rf "$outDir" && mkdir -p "$outDir" && ` +
 				`${config.JavaCmd} -jar ${config.TurbineJar} --output $out.tmp ` +
 				`--temp_dir "$outDir" --sources @$out.rsp  --source_jars $srcJars ` +
 				`--javacopts ${config.CommonJdkFlags} ` +
 				`$javacFlags -source $javaVersion -target $javaVersion $bootClasspath $classpath && ` +
 				`${config.Ziptime} $out.tmp && ` +
 				`(if cmp -s $out.tmp $out ; then rm $out.tmp ; else mv $out.tmp $out ; fi )`,
 			CommandDeps: []string{
 				"${config.TurbineJar}",
 				"${config.JavaCmd}",
 				"${config.Ziptime}",
 			},
 			Rspfile:        "$out.rsp",
 			RspfileContent: "$in",
 			Restat:         true,
 		},
 		"javacFlags", "bootClasspath", "classpath", "srcJars", "outDir", "javaVersion")

 	jar = pctx.AndroidStaticRule("jar",
 		blueprint.RuleParams{
 			Command:        `${config.SoongZipCmd} -jar -o $out @$out.rsp`,
 			CommandDeps:    []string{"${config.SoongZipCmd}"},
 			Rspfile:        "$out.rsp",
 			RspfileContent: "$jarArgs",
 		},
 		"jarArgs")

 	combineJar = pctx.AndroidStaticRule("combineJar",
 		blueprint.RuleParams{
 			Command:     `${config.MergeZipsCmd} --ignore-duplicates -j $jarArgs $out $in`,
 			CommandDeps: []string{"${config.MergeZipsCmd}"},
 		},
 		"jarArgs")

 	jarjar = pctx.AndroidStaticRule("jarjar",
 		blueprint.RuleParams{
 			Command:     "${config.JavaCmd} -jar ${config.JarjarCmd} process $rulesFile $in $out",
 			CommandDeps: []string{"${config.JavaCmd}", "${config.JarjarCmd}", "$rulesFile"},
 		},
 		"rulesFile")
 )

 func init() {
 	pctx.Import("android/soong/java/config")
 }

 type javaBuilderFlags struct {
 	javacFlags    string
 	bootClasspath classpath
 	classpath     classpath
 	systemModules classpath
 	aidlFlags     string
 	javaVersion   string

 	errorProneExtraJavacFlags string

 	kotlincFlags     string
 	kotlincClasspath classpath

 	protoFlags       []string
 	protoOutTypeFlag string // The flag itself: --java_out
 	protoOutParams   string // Parameters to that flag: --java_out=$protoOutParams:$outDir
 	protoRoot        bool
 }

 func TransformKotlinToClasses(ctx android.ModuleContext, outputFile android.WritablePath,
 	srcFiles, srcJars android.Paths,
 	flags javaBuilderFlags) {

 	inputs := append(android.Paths(nil), srcFiles...)

 	var deps android.Paths
 	deps = append(deps, flags.kotlincClasspath...)
 	deps = append(deps, srcJars...)

 	ctx.Build(pctx, android.BuildParams{
 		Rule:        kotlinc,
 		Description: "kotlinc",
 		Output:      outputFile,
 		Inputs:      inputs,
 		Implicits:   deps,
 		Args: map[string]string{
 			"classpath":    flags.kotlincClasspath.FormJavaClassPath("-classpath"),
 			"kotlincFlags": flags.kotlincFlags,
 			"srcJars":      strings.Join(srcJars.Strings(), " "),
 			"outDir":       android.PathForModuleOut(ctx, "kotlinc", "classes").String(),
 			"srcJarDir":    android.PathForModuleOut(ctx, "kotlinc", "srcJars").String(),
 			// http://b/69160377 kotlinc only supports -jvm-target 1.6 and 1.8
 			"kotlinJvmTarget": "1.8",
 		},
 	})
 }

 func TransformJavaToClasses(ctx android.ModuleContext, outputFile android.WritablePath, shardIdx int,
 	srcFiles, srcJars android.Paths, flags javaBuilderFlags, deps android.Paths) {

 	// Compile java sources into .class files
 	desc := "javac"
 	if shardIdx >= 0 {
 		desc += strconv.Itoa(shardIdx)
 	}

 	transformJavaToClasses(ctx, outputFile, shardIdx, srcFiles, srcJars, flags, deps, "javac", desc, javac)
 }

 func RunErrorProne(ctx android.ModuleContext, outputFile android.WritablePath,
 	srcFiles, srcJars android.Paths, flags javaBuilderFlags) {

 	if config.ErrorProneJar == "" {
 		ctx.ModuleErrorf("cannot build with Error Prone, missing external/error_prone?")
 	}

 	if len(flags.errorProneExtraJavacFlags) > 0 {
 		if len(flags.javacFlags) > 0 {
 			flags.javacFlags = flags.errorProneExtraJavacFlags + " " + flags.javacFlags
 		} else {
 			flags.javacFlags = flags.errorProneExtraJavacFlags
 		}
 	}

 	transformJavaToClasses(ctx, outputFile, -1, srcFiles, srcJars, flags, nil,
 		"errorprone", "errorprone", errorprone)
 }

 func TransformJavaToHeaderClasses(ctx android.ModuleContext, outputFile android.WritablePath,
 	srcFiles, srcJars android.Paths, flags javaBuilderFlags) {

 	var deps android.Paths
 	deps = append(deps, srcJars...)
 	deps = append(deps, flags.bootClasspath...)
 	deps = append(deps, flags.classpath...)

 	var bootClasspath string
 	if len(flags.bootClasspath) == 0 && ctx.Device() {
 		// explicitly specify -bootclasspath "" if the bootclasspath is empty to
 		// ensure java does not fall back to the default bootclasspath.
 		bootClasspath = `--bootclasspath ""`
 	} else {
 		bootClasspath = flags.bootClasspath.FormJavaClassPath("--bootclasspath")
 	}

 	ctx.Build(pctx, android.BuildParams{
 		Rule:        turbine,
 		Description: "turbine",
 		Output:      outputFile,
 		Inputs:      srcFiles,
 		Implicits:   deps,
 		Args: map[string]string{
 			"javacFlags":    flags.javacFlags,
 			"bootClasspath": bootClasspath,
 			"srcJars":       strings.Join(srcJars.Strings(), " "),
 			"classpath":     flags.classpath.FormJavaClassPath("--classpath"),
 			"outDir":        android.PathForModuleOut(ctx, "turbine", "classes").String(),
 			"javaVersion":   flags.javaVersion,
 		},
 	})
 }

 // transformJavaToClasses takes source files and converts them to a jar containing .class files.
 // srcFiles is a list of paths to sources, srcJars is a list of paths to jar files that contain
 // sources.  flags contains various command line flags to be passed to the compiler.
 //
 // This method may be used for different compilers, including javac and Error Prone.  The rule
 // argument specifies which command line to use and desc sets the description of the rule that will
 // be printed at build time.  The stem argument provides the file name of the output jar, and
 // suffix will be appended to various intermediate files and directories to avoid collisions when
 // this function is called twice in the same module directory.
 func transformJavaToClasses(ctx android.ModuleContext, outputFile android.WritablePath,
 	shardIdx int, srcFiles, srcJars android.Paths,
 	flags javaBuilderFlags, deps android.Paths,
 	intermediatesDir, desc string, rule blueprint.Rule) {

 	deps = append(deps, srcJars...)

 	var bootClasspath string
 	if flags.javaVersion == "1.9" {
 		deps = append(deps, flags.systemModules...)
 		bootClasspath = flags.systemModules.FormJavaSystemModulesPath("--system=", ctx.Device())
 	} else {
 		deps = append(deps, flags.bootClasspath...)
 		if len(flags.bootClasspath) == 0 && ctx.Device() {
 			// explicitly specify -bootclasspath "" if the bootclasspath is empty to
 			// ensure java does not fall back to the default bootclasspath.
 			bootClasspath = `-bootclasspath ""`
 		} else {
 			bootClasspath = flags.bootClasspath.FormJavaClassPath("-bootclasspath")
 		}
 	}

 	deps = append(deps, flags.classpath...)

 	srcJarDir := "srcjars"
 	outDir := "classes"
 	annoDir := "anno"
 	if shardIdx >= 0 {
 		shardDir := "shard" + strconv.Itoa(shardIdx)
 		srcJarDir = filepath.Join(shardDir, srcJarDir)
 		outDir = filepath.Join(shardDir, outDir)
 		annoDir = filepath.Join(shardDir, annoDir)
 	}
 	ctx.Build(pctx, android.BuildParams{
 		Rule:        rule,
 		Description: desc,
 		Output:      outputFile,
 		Inputs:      srcFiles,
 		Implicits:   deps,
 		Args: map[string]string{
 			"javacFlags":    flags.javacFlags,
 			"bootClasspath": bootClasspath,
 			"classpath":     flags.classpath.FormJavaClassPath("-classpath"),
 			"srcJars":       strings.Join(srcJars.Strings(), " "),
 			"srcJarDir":     android.PathForModuleOut(ctx, intermediatesDir, srcJarDir).String(),
 			"outDir":        android.PathForModuleOut(ctx, intermediatesDir, outDir).String(),
 			"annoDir":       android.PathForModuleOut(ctx, intermediatesDir, annoDir).String(),
 			"javaVersion":   flags.javaVersion,
 		},
 	})
 }

 func TransformResourcesToJar(ctx android.ModuleContext, outputFile android.WritablePath,
 	jarArgs []string, deps android.Paths) {

 	ctx.Build(pctx, android.BuildParams{
 		Rule:        jar,
 		Description: "jar",
 		Output:      outputFile,
 		Implicits:   deps,
 		Args: map[string]string{
 			"jarArgs": strings.Join(jarArgs, " "),
 		},
 	})
 }

 func TransformJarsToJar(ctx android.ModuleContext, outputFile android.WritablePath, desc string,
 	jars android.Paths, manifest android.OptionalPath, stripDirs bool, dirsToStrip []string) {

 	var deps android.Paths

 	var jarArgs []string
 	if manifest.Valid() {
 		jarArgs = append(jarArgs, "-m ", manifest.String())
 		deps = append(deps, manifest.Path())
 	}

 	if dirsToStrip != nil {
 		for _, dir := range dirsToStrip {
 			jarArgs = append(jarArgs, "-stripDir ", dir)
 		}
 	}

 	// Remove any module-info.class files that may have come from prebuilt jars, they cause problems
 	// for downstream tools like desugar.
 	jarArgs = append(jarArgs, "-stripFile module-info.class")

 	if stripDirs {
 		jarArgs = append(jarArgs, "-D")
 	}

 	ctx.Build(pctx, android.BuildParams{
 		Rule:        combineJar,
 		Description: desc,
 		Output:      outputFile,
 		Inputs:      jars,
 		Implicits:   deps,
 		Args: map[string]string{
 			"jarArgs": strings.Join(jarArgs, " "),
 		},
 	})
 }

 func TransformJarJar(ctx android.ModuleContext, outputFile android.WritablePath,
 	classesJar android.Path, rulesFile android.Path) {
 	ctx.Build(pctx, android.BuildParams{
 		Rule:        jarjar,
 		Description: "jarjar",
 		Output:      outputFile,
 		Input:       classesJar,
 		Implicit:    rulesFile,
 		Args: map[string]string{
 			"rulesFile": rulesFile.String(),
 		},
 	})
 }

 type classpath []android.Path

 func (x *classpath) FormJavaClassPath(optName string) string {
 	if len(*x) > 0 {
 		return optName + " " + strings.Join(x.Strings(), ":")
 	} else {
 		return ""
 	}
 }

 // Returns a --system argument in the form javac expects with -source 1.9.  If forceEmpty is true,
 // returns --system=none if the list is empty to ensure javac does not fall back to the default
 // system modules.
 func (x *classpath) FormJavaSystemModulesPath(optName string, forceEmpty bool) string {
 	if len(*x) > 1 {
 		panic("more than one system module")
 	} else if len(*x) == 1 {
 		return optName + strings.TrimSuffix((*x)[0].String(), "lib/modules")
 	} else if forceEmpty {
 		return optName + "none"
 	} else {
 		return ""
 	}
 }

 func (x *classpath) FormDesugarClasspath(optName string) []string {
 	if x == nil || *x == nil {
 		return nil
 	}
 	flags := make([]string, len(*x))
 	for i, v := range *x {
 		flags[i] = optName + " " + v.String()
 	}

 	return flags
 }

 // Convert a classpath to an android.Paths
 func (x *classpath) Paths() android.Paths {
 	return append(android.Paths(nil), (*x)...)
 }

 func (x *classpath) Strings() []string {
 	if x == nil {
 		return nil
 	}
 	ret := make([]string, len(*x))
 	for i, path := range *x {
 		ret[i] = path.String()
 	}
 	return ret
 }
	// Copyright 2015 Google Inc. 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.

	package java

	// This file generates the final rules for compiling all Java. All properties related to
	// compiling should have been translated into javaBuilderFlags or another argument to the Transform*
	// functions.

	import (
	"path/filepath"
	"strconv"
	"strings"

	"github.com/google/blueprint"

	"android/soong/android"
	"android/soong/java/config"
	)

	var (
	pctx = android.NewPackageContext("android/soong/java")

	// Compiling java is not conducive to proper dependency tracking. The path-matches-class-name
	// requirement leads to unpredictable generated source file names, and a single .java file
	// will get compiled into multiple .class files if it contains inner classes. To work around
	// this, all java rules write into separate directories and then are combined into a .jar file
	// (if the rule produces .class files) or a .srcjar file (if the rule produces .java files).
	// .srcjar files are unzipped into a temporary directory when compiled with javac.
	javac = pctx.AndroidGomaStaticRule("javac",
	blueprint.RuleParams{
	Command: `rm -rf "$outDir" "$annoDir" "$srcJarDir" && mkdir -p "$outDir" "$annoDir" "$srcJarDir" && ` +
	`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
	`${config.SoongJavacWrapper} ${config.JavacWrapper}${config.JavacCmd} ${config.JavacHeapFlags} ${config.CommonJdkFlags} ` +
	`$javacFlags $bootClasspath $classpath ` +
	`-source $javaVersion -target $javaVersion ` +
	`-d $outDir -s $annoDir @$out.rsp @$srcJarDir/list && ` +
	`${config.SoongZipCmd} -jar -o $out -C $outDir -D $outDir`,
	CommandDeps: []string{
	"${config.JavacCmd}",
	"${config.SoongZipCmd}",
	"${config.ZipSyncCmd}",
	},
	CommandOrderOnly: []string{"${config.SoongJavacWrapper}"},
	Rspfile: "$out.rsp",
	RspfileContent: "$in",
	},
	"javacFlags", "bootClasspath", "classpath", "srcJars", "srcJarDir",
	"outDir", "annoDir", "javaVersion")

	kotlinc = pctx.AndroidGomaStaticRule("kotlinc",
	blueprint.RuleParams{
	Command: `rm -rf "$outDir" "$srcJarDir" && mkdir -p "$outDir" "$srcJarDir" && ` +
	`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
	`${config.GenKotlinBuildFileCmd} $classpath $outDir $out.rsp $srcJarDir/list > $outDir/kotlinc-build.xml &&` +
	`${config.KotlincCmd} $kotlincFlags ` +
	`-jvm-target $kotlinJvmTarget -Xbuild-file=$outDir/kotlinc-build.xml && ` +
	`${config.SoongZipCmd} -jar -o $out -C $outDir -D $outDir`,
	CommandDeps: []string{
	"${config.KotlincCmd}",
	"${config.KotlinCompilerJar}",
	"${config.GenKotlinBuildFileCmd}",
	"${config.SoongZipCmd}",
	"${config.ZipSyncCmd}",
	},
	Rspfile: "$out.rsp",
	RspfileContent: `$in`,
	},
	"kotlincFlags", "classpath", "srcJars", "srcJarDir", "outDir", "kotlinJvmTarget")

	errorprone = pctx.AndroidStaticRule("errorprone",
	blueprint.RuleParams{
	Command: `rm -rf "$outDir" "$annoDir" "$srcJarDir" && mkdir -p "$outDir" "$annoDir" "$srcJarDir" && ` +
	`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
	`${config.SoongJavacWrapper} ${config.ErrorProneCmd} ` +
	`$javacFlags $bootClasspath $classpath ` +
	`-source $javaVersion -target $javaVersion ` +
	`-d $outDir -s $annoDir @$out.rsp @$srcJarDir/list && ` +
	`${config.SoongZipCmd} -jar -o $out -C $outDir -D $outDir`,
	CommandDeps: []string{
	"${config.JavaCmd}",
	"${config.ErrorProneJavacJar}",
	"${config.ErrorProneJar}",
	"${config.SoongZipCmd}",
	"${config.ZipSyncCmd}",
	},
	CommandOrderOnly: []string{"${config.SoongJavacWrapper}"},
	Rspfile: "$out.rsp",
	RspfileContent: "$in",
	},
	"javacFlags", "bootClasspath", "classpath", "srcJars", "srcJarDir",
	"outDir", "annoDir", "javaVersion")

	turbine = pctx.AndroidStaticRule("turbine",
	blueprint.RuleParams{
	Command: `rm -rf "$outDir" && mkdir -p "$outDir" && ` +
	`${config.JavaCmd} -jar ${config.TurbineJar} --output $out.tmp ` +
	`--temp_dir "$outDir" --sources @$out.rsp --source_jars $srcJars ` +
	`--javacopts ${config.CommonJdkFlags} ` +
	`$javacFlags -source $javaVersion -target $javaVersion $bootClasspath $classpath && ` +
	`${config.Ziptime} $out.tmp && ` +
	`(if cmp -s $out.tmp $out ; then rm $out.tmp ; else mv $out.tmp $out ; fi )`,
	CommandDeps: []string{
	"${config.TurbineJar}",
	"${config.JavaCmd}",
	"${config.Ziptime}",
	},
	Rspfile: "$out.rsp",
	RspfileContent: "$in",
	Restat: true,
	},
	"javacFlags", "bootClasspath", "classpath", "srcJars", "outDir", "javaVersion")

	jar = pctx.AndroidStaticRule("jar",
	blueprint.RuleParams{
	Command: `${config.SoongZipCmd} -jar -o $out @$out.rsp`,
	CommandDeps: []string{"${config.SoongZipCmd}"},
	Rspfile: "$out.rsp",
	RspfileContent: "$jarArgs",
	},
	"jarArgs")

	combineJar = pctx.AndroidStaticRule("combineJar",
	blueprint.RuleParams{
	Command: `${config.MergeZipsCmd} --ignore-duplicates -j $jarArgs $out $in`,
	CommandDeps: []string{"${config.MergeZipsCmd}"},
	},
	"jarArgs")

	jarjar = pctx.AndroidStaticRule("jarjar",
	blueprint.RuleParams{
	Command: "${config.JavaCmd} -jar ${config.JarjarCmd} process $rulesFile $in $out",
	CommandDeps: []string{"${config.JavaCmd}", "${config.JarjarCmd}", "$rulesFile"},
	},
	"rulesFile")
	)

	func init() {
	pctx.Import("android/soong/java/config")
	}

	type javaBuilderFlags struct {
	javacFlags string
	bootClasspath classpath
	classpath classpath
	systemModules classpath
	aidlFlags string
	javaVersion string

	errorProneExtraJavacFlags string

	kotlincFlags string
	kotlincClasspath classpath

	protoFlags []string
	protoOutTypeFlag string // The flag itself: --java_out
	protoOutParams string // Parameters to that flag: --java_out=$protoOutParams:$outDir
	protoRoot bool
	}

	func TransformKotlinToClasses(ctx android.ModuleContext, outputFile android.WritablePath,
	srcFiles, srcJars android.Paths,
	flags javaBuilderFlags) {

	inputs := append(android.Paths(nil), srcFiles...)

	var deps android.Paths
	deps = append(deps, flags.kotlincClasspath...)
	deps = append(deps, srcJars...)

	ctx.Build(pctx, android.BuildParams{
	Rule: kotlinc,
	Description: "kotlinc",
	Output: outputFile,
	Inputs: inputs,
	Implicits: deps,
	Args: map[string]string{
	"classpath": flags.kotlincClasspath.FormJavaClassPath("-classpath"),
	"kotlincFlags": flags.kotlincFlags,
	"srcJars": strings.Join(srcJars.Strings(), " "),
	"outDir": android.PathForModuleOut(ctx, "kotlinc", "classes").String(),
	"srcJarDir": android.PathForModuleOut(ctx, "kotlinc", "srcJars").String(),
	// http://b/69160377 kotlinc only supports -jvm-target 1.6 and 1.8
	"kotlinJvmTarget": "1.8",
	},
	})
	}

	func TransformJavaToClasses(ctx android.ModuleContext, outputFile android.WritablePath, shardIdx int,
	srcFiles, srcJars android.Paths, flags javaBuilderFlags, deps android.Paths) {

	// Compile java sources into .class files
	desc := "javac"
	if shardIdx >= 0 {
	desc += strconv.Itoa(shardIdx)
	}

	transformJavaToClasses(ctx, outputFile, shardIdx, srcFiles, srcJars, flags, deps, "javac", desc, javac)
	}

	func RunErrorProne(ctx android.ModuleContext, outputFile android.WritablePath,
	srcFiles, srcJars android.Paths, flags javaBuilderFlags) {

	if config.ErrorProneJar == "" {
	ctx.ModuleErrorf("cannot build with Error Prone, missing external/error_prone?")
	}

	if len(flags.errorProneExtraJavacFlags) > 0 {
	if len(flags.javacFlags) > 0 {
	flags.javacFlags = flags.errorProneExtraJavacFlags + " " + flags.javacFlags
	} else {
	flags.javacFlags = flags.errorProneExtraJavacFlags
	}
	}

	transformJavaToClasses(ctx, outputFile, -1, srcFiles, srcJars, flags, nil,
	"errorprone", "errorprone", errorprone)
	}

	func TransformJavaToHeaderClasses(ctx android.ModuleContext, outputFile android.WritablePath,
	srcFiles, srcJars android.Paths, flags javaBuilderFlags) {

	var deps android.Paths
	deps = append(deps, srcJars...)
	deps = append(deps, flags.bootClasspath...)
	deps = append(deps, flags.classpath...)

	var bootClasspath string
	if len(flags.bootClasspath) == 0 && ctx.Device() {
	// explicitly specify -bootclasspath "" if the bootclasspath is empty to
	// ensure java does not fall back to the default bootclasspath.
	bootClasspath = `--bootclasspath ""`
	} else {
	bootClasspath = flags.bootClasspath.FormJavaClassPath("--bootclasspath")
	}

	ctx.Build(pctx, android.BuildParams{
	Rule: turbine,
	Description: "turbine",
	Output: outputFile,
	Inputs: srcFiles,
	Implicits: deps,
	Args: map[string]string{
	"javacFlags": flags.javacFlags,
	"bootClasspath": bootClasspath,
	"srcJars": strings.Join(srcJars.Strings(), " "),
	"classpath": flags.classpath.FormJavaClassPath("--classpath"),
	"outDir": android.PathForModuleOut(ctx, "turbine", "classes").String(),
	"javaVersion": flags.javaVersion,
	},
	})
	}

	// transformJavaToClasses takes source files and converts them to a jar containing .class files.
	// srcFiles is a list of paths to sources, srcJars is a list of paths to jar files that contain
	// sources. flags contains various command line flags to be passed to the compiler.
	//
	// This method may be used for different compilers, including javac and Error Prone. The rule
	// argument specifies which command line to use and desc sets the description of the rule that will
	// be printed at build time. The stem argument provides the file name of the output jar, and
	// suffix will be appended to various intermediate files and directories to avoid collisions when
	// this function is called twice in the same module directory.
	func transformJavaToClasses(ctx android.ModuleContext, outputFile android.WritablePath,
	shardIdx int, srcFiles, srcJars android.Paths,
	flags javaBuilderFlags, deps android.Paths,
	intermediatesDir, desc string, rule blueprint.Rule) {

	deps = append(deps, srcJars...)

	var bootClasspath string
	if flags.javaVersion == "1.9" {
	deps = append(deps, flags.systemModules...)
	bootClasspath = flags.systemModules.FormJavaSystemModulesPath("--system=", ctx.Device())
	} else {
	deps = append(deps, flags.bootClasspath...)
	if len(flags.bootClasspath) == 0 && ctx.Device() {
	// explicitly specify -bootclasspath "" if the bootclasspath is empty to
	// ensure java does not fall back to the default bootclasspath.
	bootClasspath = `-bootclasspath ""`
	} else {
	bootClasspath = flags.bootClasspath.FormJavaClassPath("-bootclasspath")
	}
	}

	deps = append(deps, flags.classpath...)

	srcJarDir := "srcjars"
	outDir := "classes"
	annoDir := "anno"
	if shardIdx >= 0 {
	shardDir := "shard" + strconv.Itoa(shardIdx)
	srcJarDir = filepath.Join(shardDir, srcJarDir)
	outDir = filepath.Join(shardDir, outDir)
	annoDir = filepath.Join(shardDir, annoDir)
	}
	ctx.Build(pctx, android.BuildParams{
	Rule: rule,
	Description: desc,
	Output: outputFile,
	Inputs: srcFiles,
	Implicits: deps,
	Args: map[string]string{
	"javacFlags": flags.javacFlags,
	"bootClasspath": bootClasspath,
	"classpath": flags.classpath.FormJavaClassPath("-classpath"),
	"srcJars": strings.Join(srcJars.Strings(), " "),
	"srcJarDir": android.PathForModuleOut(ctx, intermediatesDir, srcJarDir).String(),
	"outDir": android.PathForModuleOut(ctx, intermediatesDir, outDir).String(),
	"annoDir": android.PathForModuleOut(ctx, intermediatesDir, annoDir).String(),
	"javaVersion": flags.javaVersion,
	},
	})
	}

	func TransformResourcesToJar(ctx android.ModuleContext, outputFile android.WritablePath,
	jarArgs []string, deps android.Paths) {

	ctx.Build(pctx, android.BuildParams{
	Rule: jar,
	Description: "jar",
	Output: outputFile,
	Implicits: deps,
	Args: map[string]string{
	"jarArgs": strings.Join(jarArgs, " "),
	},
	})
	}

	func TransformJarsToJar(ctx android.ModuleContext, outputFile android.WritablePath, desc string,
	jars android.Paths, manifest android.OptionalPath, stripDirs bool, dirsToStrip []string) {

	var deps android.Paths

	var jarArgs []string
	if manifest.Valid() {
	jarArgs = append(jarArgs, "-m ", manifest.String())
	deps = append(deps, manifest.Path())
	}

	if dirsToStrip != nil {
	for _, dir := range dirsToStrip {
	jarArgs = append(jarArgs, "-stripDir ", dir)
	}
	}

	// Remove any module-info.class files that may have come from prebuilt jars, they cause problems
	// for downstream tools like desugar.
	jarArgs = append(jarArgs, "-stripFile module-info.class")

	if stripDirs {
	jarArgs = append(jarArgs, "-D")
	}

	ctx.Build(pctx, android.BuildParams{
	Rule: combineJar,
	Description: desc,
	Output: outputFile,
	Inputs: jars,
	Implicits: deps,
	Args: map[string]string{
	"jarArgs": strings.Join(jarArgs, " "),
	},
	})
	}

	func TransformJarJar(ctx android.ModuleContext, outputFile android.WritablePath,
	classesJar android.Path, rulesFile android.Path) {
	ctx.Build(pctx, android.BuildParams{
	Rule: jarjar,
	Description: "jarjar",
	Output: outputFile,
	Input: classesJar,
	Implicit: rulesFile,
	Args: map[string]string{
	"rulesFile": rulesFile.String(),
	},
	})
	}

	type classpath []android.Path

	func (x *classpath) FormJavaClassPath(optName string) string {
	if len(*x) > 0 {
	return optName + " " + strings.Join(x.Strings(), ":")
	} else {
	return ""
	}
	}

	// Returns a --system argument in the form javac expects with -source 1.9. If forceEmpty is true,
	// returns --system=none if the list is empty to ensure javac does not fall back to the default
	// system modules.
	func (x *classpath) FormJavaSystemModulesPath(optName string, forceEmpty bool) string {
	if len(*x) > 1 {
	panic("more than one system module")
	} else if len(*x) == 1 {
	return optName + strings.TrimSuffix((*x)[0].String(), "lib/modules")
	} else if forceEmpty {
	return optName + "none"
	} else {
	return ""
	}
	}

	func (x *classpath) FormDesugarClasspath(optName string) []string {
	if x == nil \|\| *x == nil {
	return nil
	}
	flags := make([]string, len(*x))
	for i, v := range *x {
	flags[i] = optName + " " + v.String()
	}

	return flags
	}

	// Convert a classpath to an android.Paths
	func (x *classpath) Paths() android.Paths {
	return append(android.Paths(nil), (*x)...)
	}

	func (x *classpath) Strings() []string {
	if x == nil {
	return nil
	}
	ret := make([]string, len(*x))
	for i, path := range *x {
	ret[i] = path.String()
	}
	return ret
	}