cmd/pom2mk/pom2mk.go - platform/build/soong - Git at Google

 // Copyright 2017 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 main

 import (
 	"bufio"
 	"bytes"
 	"encoding/xml"
 	"flag"
 	"fmt"
 	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"regexp"
 	"sort"
 	"strings"
 	"text/template"

 	"github.com/google/blueprint/proptools"
 )

 type RewriteNames []RewriteName
 type RewriteName struct {
 	regexp *regexp.Regexp
 	repl   string
 }

 func (r *RewriteNames) String() string {
 	return ""
 }

 func (r *RewriteNames) Set(v string) error {
 	split := strings.SplitN(v, "=", 2)
 	if len(split) != 2 {
 		return fmt.Errorf("Must be in the form of <regex>=<replace>")
 	}
 	regex, err := regexp.Compile(split[0])
 	if err != nil {
 		return nil
 	}
 	*r = append(*r, RewriteName{
 		regexp: regex,
 		repl:   split[1],
 	})
 	return nil
 }

 func (r *RewriteNames) MavenToMk(groupId string, artifactId string) string {
 	for _, r := range *r {
 		if r.regexp.MatchString(groupId + ":" + artifactId) {
 			return r.regexp.ReplaceAllString(groupId+":"+artifactId, r.repl)
 		} else if r.regexp.MatchString(artifactId) {
 			return r.regexp.ReplaceAllString(artifactId, r.repl)
 		}
 	}
 	return artifactId
 }

 var rewriteNames = RewriteNames{}

 type ExtraDeps map[string][]string

 func (d ExtraDeps) String() string {
 	return ""
 }

 func (d ExtraDeps) Set(v string) error {
 	split := strings.SplitN(v, "=", 2)
 	if len(split) != 2 {
 		return fmt.Errorf("Must be in the form of <module>=<module>[,<module>]")
 	}
 	d[split[0]] = strings.Split(split[1], ",")
 	return nil
 }

 var extraDeps = make(ExtraDeps)

 type Exclude map[string]bool

 func (e Exclude) String() string {
 	return ""
 }

 func (e Exclude) Set(v string) error {
 	e[v] = true
 	return nil
 }

 var excludes = make(Exclude)

 var sdkVersion string
 var useVersion string
 var staticDeps bool

 func InList(s string, list []string) bool {
 	for _, l := range list {
 		if l == s {
 			return true
 		}
 	}

 	return false
 }

 type Dependency struct {
 	XMLName xml.Name `xml:"dependency"`

 	MakeTarget string `xml:"-"`

 	GroupId    string `xml:"groupId"`
 	ArtifactId string `xml:"artifactId"`
 	Version    string `xml:"version"`
 	Type       string `xml:"type"`
 	Scope      string `xml:"scope"`
 }

 func (d Dependency) MkName() string {
 	if d.MakeTarget == "" {
 		d.MakeTarget = rewriteNames.MavenToMk(d.GroupId, d.ArtifactId)
 	}
 	return d.MakeTarget
 }

 type Pom struct {
 	XMLName xml.Name `xml:"http://maven.apache.org/POM/4.0.0 project"`

 	PomFile      string `xml:"-"`
 	ArtifactFile string `xml:"-"`
 	MakeTarget   string `xml:"-"`

 	GroupId    string `xml:"groupId"`
 	ArtifactId string `xml:"artifactId"`
 	Version    string `xml:"version"`
 	Packaging  string `xml:"packaging"`

 	Dependencies []*Dependency `xml:"dependencies>dependency"`
 }

 func (p Pom) IsAar() bool {
 	return p.Packaging == "aar"
 }

 func (p Pom) IsJar() bool {
 	return p.Packaging == "jar"
 }

 func (p Pom) MkName() string {
 	if p.MakeTarget == "" {
 		p.MakeTarget = rewriteNames.MavenToMk(p.GroupId, p.ArtifactId)
 	}
 	return p.MakeTarget
 }

 func (p Pom) MkJarDeps() []string {
 	return p.MkDeps("jar", []string{"compile", "runtime"})
 }

 func (p Pom) MkAarDeps() []string {
 	return p.MkDeps("aar", []string{"compile", "runtime"})
 }

 // MkDeps obtains dependencies filtered by type and scope. The results of this
 // method are formatted as Make targets, e.g. run through MavenToMk rules.
 func (p Pom) MkDeps(typeExt string, scopes []string) []string {
 	var ret []string
 	if typeExt == "jar" {
 		// all top-level extra deps are assumed to be of type "jar" until we add syntax to specify other types
 		ret = append(ret, extraDeps[p.MkName()]...)
 	}
 	for _, d := range p.Dependencies {
 		if d.Type != typeExt || !InList(d.Scope, scopes) {
 			continue
 		}
 		name := rewriteNames.MavenToMk(d.GroupId, d.ArtifactId)
 		ret = append(ret, name)
 		ret = append(ret, extraDeps[name]...)
 	}
 	return ret
 }

 func (p Pom) SdkVersion() string {
 	return sdkVersion
 }

 func (p *Pom) FixDeps(modules map[string]*Pom) {
 	for _, d := range p.Dependencies {
 		if d.Type == "" {
 			if depPom, ok := modules[d.MkName()]; ok {
 				// We've seen the POM for this dependency, use its packaging
 				// as the dependency type rather than Maven spec default.
 				d.Type = depPom.Packaging
 			} else {
 				// Dependency type was not specified and we don't have the POM
 				// for this artifact, use the default from Maven spec.
 				d.Type = "jar"
 			}
 		}
 		if d.Scope == "" {
 			// Scope was not specified, use the default from Maven spec.
 			d.Scope = "compile"
 		}
 	}
 }

 var mkTemplate = template.Must(template.New("mk").Parse(`
 include $(CLEAR_VARS)
 LOCAL_MODULE := {{.MkName}}
 LOCAL_MODULE_CLASS := JAVA_LIBRARIES
 LOCAL_UNINSTALLABLE_MODULE := true
 LOCAL_SRC_FILES := {{.ArtifactFile}}
 LOCAL_BUILT_MODULE_STEM := javalib.jar
 LOCAL_MODULE_SUFFIX := .{{.Packaging}}
 LOCAL_USE_AAPT2 := true
 LOCAL_SDK_VERSION := {{.SdkVersion}}
 LOCAL_STATIC_JAVA_LIBRARIES :={{range .MkJarDeps}} \
   {{.}}{{end}}
 LOCAL_STATIC_ANDROID_LIBRARIES :={{range .MkAarDeps}} \
   {{.}}{{end}}
 include $(BUILD_PREBUILT)
 `))

 var mkDepsTemplate = template.Must(template.New("mk").Parse(`
 include $(CLEAR_VARS)
 LOCAL_MODULE := {{.MkName}}-nodeps
 LOCAL_MODULE_CLASS := JAVA_LIBRARIES
 LOCAL_UNINSTALLABLE_MODULE := true
 LOCAL_SRC_FILES := {{.ArtifactFile}}
 LOCAL_BUILT_MODULE_STEM := javalib.jar
 LOCAL_MODULE_SUFFIX := .{{.Packaging}}
 LOCAL_USE_AAPT2 := true
 LOCAL_SDK_VERSION := {{.SdkVersion}}
 LOCAL_STATIC_ANDROID_LIBRARIES :={{range .MkAarDeps}} \
   {{.}}{{end}}
 include $(BUILD_PREBUILT)
 include $(CLEAR_VARS)
 LOCAL_MODULE := {{.MkName}}
 LOCAL_SDK_VERSION := {{.SdkVersion}}{{if .IsAar}}
 LOCAL_MANIFEST_FILE := manifests/{{.MkName}}/AndroidManifest.xml{{end}}
 LOCAL_STATIC_JAVA_LIBRARIES :={{if .IsJar}} \
   {{.MkName}}-nodeps{{end}}{{range .MkJarDeps}} \
   {{.}}{{end}}
 LOCAL_STATIC_ANDROID_LIBRARIES :={{if .IsAar}} \
   {{.MkName}}-nodeps{{end}}{{range .MkAarDeps}}  \
   {{.}}{{end}}
 LOCAL_JAR_EXCLUDE_FILES := none
 LOCAL_JAVA_LANGUAGE_VERSION := 1.7
 LOCAL_USE_AAPT2 := true
 include $(BUILD_STATIC_JAVA_LIBRARY)
 `))

 func parse(filename string) (*Pom, error) {
 	data, err := ioutil.ReadFile(filename)
 	if err != nil {
 		return nil, err
 	}

 	var pom Pom
 	err = xml.Unmarshal(data, &pom)
 	if err != nil {
 		return nil, err
 	}

 	if useVersion != "" && pom.Version != useVersion {
 		return nil, nil
 	}

 	if pom.Packaging == "" {
 		pom.Packaging = "jar"
 	}

 	pom.PomFile = filename
 	pom.ArtifactFile = strings.TrimSuffix(filename, ".pom") + "." + pom.Packaging

 	return &pom, nil
 }

 func rerunForRegen(filename string) error {
 	buf, err := ioutil.ReadFile(filename)
 	if err != nil {
 		return err
 	}

 	scanner := bufio.NewScanner(bytes.NewBuffer(buf))

 	// Skip the first line in the file
 	for i := 0; i < 2; i++ {
 		if !scanner.Scan() {
 			if scanner.Err() != nil {
 				return scanner.Err()
 			} else {
 				return fmt.Errorf("unexpected EOF")
 			}
 		}
 	}

 	// Extract the old args from the file
 	line := scanner.Text()
 	if strings.HasPrefix(line, "# pom2mk ") {
 		line = strings.TrimPrefix(line, "# pom2mk ")
 	} else {
 		return fmt.Errorf("unexpected second line: %q", line)
 	}
 	args := strings.Split(line, " ")
 	lastArg := args[len(args)-1]
 	args = args[:len(args)-1]

 	// Append all current command line args except -regen <file> to the ones from the file
 	for i := 1; i < len(os.Args); i++ {
 		if os.Args[i] == "-regen" {
 			i++
 		} else {
 			args = append(args, os.Args[i])
 		}
 	}
 	args = append(args, lastArg)

 	cmd := os.Args[0] + " " + strings.Join(args, " ")
 	// Re-exec pom2mk with the new arguments
 	output, err := exec.Command("/bin/sh", "-c", cmd).Output()
 	if exitErr, _ := err.(*exec.ExitError); exitErr != nil {
 		return fmt.Errorf("failed to run %s\n%s", cmd, string(exitErr.Stderr))
 	} else if err != nil {
 		return err
 	}

 	return ioutil.WriteFile(filename, output, 0666)
 }

 func main() {
 	flag.Usage = func() {
 		fmt.Fprintf(os.Stderr, `pom2mk, a tool to create Android.mk files from maven repos

 The tool will extract the necessary information from *.pom files to create an Android.mk whose
 aar libraries can be linked against when using AAPT2.

 Usage: %s [--rewrite <regex>=<replace>] [-exclude <module>] [--extra-deps <module>=<module>[,<module>]] [<dir>] [-regen <file>]

   -rewrite <regex>=<replace>
      rewrite can be used to specify mappings between Maven projects and Make modules. The -rewrite
      option can be specified multiple times. When determining the Make module for a given Maven
      project, mappings are searched in the order they were specified. The first <regex> matching
      either the Maven project's <groupId>:<artifactId> or <artifactId> will be used to generate
      the Make module name using <replace>. If no matches are found, <artifactId> is used.
   -exclude <module>
      Don't put the specified module in the makefile.
   -extra-deps <module>=<module>[,<module>]
      Some Android.mk modules have transitive dependencies that must be specified when they are
      depended upon (like android-support-v7-mediarouter requires android-support-v7-appcompat).
      This may be specified multiple times to declare these dependencies.
   -sdk-version <version>
      Sets LOCAL_SDK_VERSION := <version> for all modules.
   -use-version <version>
      If the maven directory contains multiple versions of artifacts and their pom files,
      -use-version can be used to only write makefiles for a specific version of those artifacts.
   -static-deps
      Whether to statically include direct dependencies.
   <dir>
      The directory to search for *.pom files under.
      The makefile is written to stdout, to be put in the current directory (often as Android.mk)
   -regen <file>
      Read arguments from <file> and overwrite it.
 `, os.Args[0])
 	}

 	var regen string

 	flag.Var(&excludes, "exclude", "Exclude module")
 	flag.Var(&extraDeps, "extra-deps", "Extra dependencies needed when depending on a module")
 	flag.Var(&rewriteNames, "rewrite", "Regex(es) to rewrite artifact names")
 	flag.StringVar(&sdkVersion, "sdk-version", "", "What to write to LOCAL_SDK_VERSION")
 	flag.StringVar(&useVersion, "use-version", "", "Only read artifacts of a specific version")
 	flag.BoolVar(&staticDeps, "static-deps", false, "Statically include direct dependencies")
 	flag.StringVar(&regen, "regen", "", "Rewrite specified file")
 	flag.Parse()

 	if regen != "" {
 		err := rerunForRegen(regen)
 		if err != nil {
 			fmt.Fprintln(os.Stderr, err)
 			os.Exit(1)
 		}
 		os.Exit(0)
 	}

 	if flag.NArg() == 0 {
 		fmt.Fprintln(os.Stderr, "Directory argument is required")
 		os.Exit(1)
 	} else if flag.NArg() > 1 {
 		fmt.Fprintln(os.Stderr, "Multiple directories provided:", strings.Join(flag.Args(), " "))
 		os.Exit(1)
 	}

 	dir := flag.Arg(0)
 	absDir, err := filepath.Abs(dir)
 	if err != nil {
 		fmt.Fprintln(os.Stderr, "Failed to get absolute directory:", err)
 		os.Exit(1)
 	}

 	var filenames []string
 	err = filepath.Walk(absDir, func(path string, info os.FileInfo, err error) error {
 		if err != nil {
 			return err
 		}

 		name := info.Name()
 		if info.IsDir() {
 			if strings.HasPrefix(name, ".") {
 				return filepath.SkipDir
 			}
 			return nil
 		}

 		if strings.HasPrefix(name, ".") {
 			return nil
 		}

 		if strings.HasSuffix(name, ".pom") {
 			path, err = filepath.Rel(absDir, path)
 			if err != nil {
 				return err
 			}
 			filenames = append(filenames, filepath.Join(dir, path))
 		}
 		return nil
 	})
 	if err != nil {
 		fmt.Fprintln(os.Stderr, "Error walking files:", err)
 		os.Exit(1)
 	}

 	if len(filenames) == 0 {
 		fmt.Fprintln(os.Stderr, "Error: no *.pom files found under", dir)
 		os.Exit(1)
 	}

 	sort.Strings(filenames)

 	poms := []*Pom{}
 	modules := make(map[string]*Pom)
 	duplicate := false
 	for _, filename := range filenames {
 		pom, err := parse(filename)
 		if err != nil {
 			fmt.Fprintln(os.Stderr, "Error converting", filename, err)
 			os.Exit(1)
 		}

 		if pom != nil {
 			key := pom.MkName()
 			if excludes[key] {
 				continue
 			}

 			if old, ok := modules[key]; ok {
 				fmt.Fprintln(os.Stderr, "Module", key, "defined twice:", old.PomFile, pom.PomFile)
 				duplicate = true
 			}

 			poms = append(poms, pom)
 			modules[key] = pom
 		}
 	}
 	if duplicate {
 		os.Exit(1)
 	}

 	for _, pom := range poms {
 		pom.FixDeps(modules)
 	}

 	fmt.Println("# Automatically generated with:")
 	fmt.Println("# pom2mk", strings.Join(proptools.ShellEscape(os.Args[1:]), " "))
 	fmt.Println("LOCAL_PATH := $(call my-dir)")

 	for _, pom := range poms {
 		var err error
 		if staticDeps {
 			err = mkDepsTemplate.Execute(os.Stdout, pom)
 		} else {
 			err = mkTemplate.Execute(os.Stdout, pom)
 		}
 		if err != nil {
 			fmt.Fprintln(os.Stderr, "Error writing", pom.PomFile, pom.MkName(), err)
 			os.Exit(1)
 		}
 	}
 }
	// Copyright 2017 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 main

	import (
	"bufio"
	"bytes"
	"encoding/xml"
	"flag"
	"fmt"
	"io/ioutil"
	"os"
	"os/exec"
	"path/filepath"
	"regexp"
	"sort"
	"strings"
	"text/template"

	"github.com/google/blueprint/proptools"
	)

	type RewriteNames []RewriteName
	type RewriteName struct {
	regexp *regexp.Regexp
	repl string
	}

	func (r *RewriteNames) String() string {
	return ""
	}

	func (r *RewriteNames) Set(v string) error {
	split := strings.SplitN(v, "=", 2)
	if len(split) != 2 {
	return fmt.Errorf("Must be in the form of <regex>=<replace>")
	}
	regex, err := regexp.Compile(split[0])
	if err != nil {
	return nil
	}
	r = append(r, RewriteName{
	regexp: regex,
	repl: split[1],
	})
	return nil
	}

	func (r *RewriteNames) MavenToMk(groupId string, artifactId string) string {
	for _, r := range *r {
	if r.regexp.MatchString(groupId + ":" + artifactId) {
	return r.regexp.ReplaceAllString(groupId+":"+artifactId, r.repl)
	} else if r.regexp.MatchString(artifactId) {
	return r.regexp.ReplaceAllString(artifactId, r.repl)
	}
	}
	return artifactId
	}

	var rewriteNames = RewriteNames{}

	type ExtraDeps map[string][]string

	func (d ExtraDeps) String() string {
	return ""
	}

	func (d ExtraDeps) Set(v string) error {
	split := strings.SplitN(v, "=", 2)
	if len(split) != 2 {
	return fmt.Errorf("Must be in the form of <module>=<module>[,<module>]")
	}
	d[split[0]] = strings.Split(split[1], ",")
	return nil
	}

	var extraDeps = make(ExtraDeps)

	type Exclude map[string]bool

	func (e Exclude) String() string {
	return ""
	}

	func (e Exclude) Set(v string) error {
	e[v] = true
	return nil
	}

	var excludes = make(Exclude)

	var sdkVersion string
	var useVersion string
	var staticDeps bool

	func InList(s string, list []string) bool {
	for _, l := range list {
	if l == s {
	return true
	}
	}

	return false
	}

	type Dependency struct {
	XMLName xml.Name `xml:"dependency"`

	MakeTarget string `xml:"-"`

	GroupId string `xml:"groupId"`
	ArtifactId string `xml:"artifactId"`
	Version string `xml:"version"`
	Type string `xml:"type"`
	Scope string `xml:"scope"`
	}

	func (d Dependency) MkName() string {
	if d.MakeTarget == "" {
	d.MakeTarget = rewriteNames.MavenToMk(d.GroupId, d.ArtifactId)
	}
	return d.MakeTarget
	}

	type Pom struct {
	XMLName xml.Name `xml:"http://maven.apache.org/POM/4.0.0 project"`

	PomFile string `xml:"-"`
	ArtifactFile string `xml:"-"`
	MakeTarget string `xml:"-"`

	GroupId string `xml:"groupId"`
	ArtifactId string `xml:"artifactId"`
	Version string `xml:"version"`
	Packaging string `xml:"packaging"`

	Dependencies []*Dependency `xml:"dependencies>dependency"`
	}

	func (p Pom) IsAar() bool {
	return p.Packaging == "aar"
	}

	func (p Pom) IsJar() bool {
	return p.Packaging == "jar"
	}

	func (p Pom) MkName() string {
	if p.MakeTarget == "" {
	p.MakeTarget = rewriteNames.MavenToMk(p.GroupId, p.ArtifactId)
	}
	return p.MakeTarget
	}

	func (p Pom) MkJarDeps() []string {
	return p.MkDeps("jar", []string{"compile", "runtime"})
	}

	func (p Pom) MkAarDeps() []string {
	return p.MkDeps("aar", []string{"compile", "runtime"})
	}

	// MkDeps obtains dependencies filtered by type and scope. The results of this
	// method are formatted as Make targets, e.g. run through MavenToMk rules.
	func (p Pom) MkDeps(typeExt string, scopes []string) []string {
	var ret []string
	if typeExt == "jar" {
	// all top-level extra deps are assumed to be of type "jar" until we add syntax to specify other types
	ret = append(ret, extraDeps[p.MkName()]...)
	}
	for _, d := range p.Dependencies {
	if d.Type != typeExt \|\| !InList(d.Scope, scopes) {
	continue
	}
	name := rewriteNames.MavenToMk(d.GroupId, d.ArtifactId)
	ret = append(ret, name)
	ret = append(ret, extraDeps[name]...)
	}
	return ret
	}

	func (p Pom) SdkVersion() string {
	return sdkVersion
	}

	func (p Pom) FixDeps(modules map[string]Pom) {
	for _, d := range p.Dependencies {
	if d.Type == "" {
	if depPom, ok := modules[d.MkName()]; ok {
	// We've seen the POM for this dependency, use its packaging
	// as the dependency type rather than Maven spec default.
	d.Type = depPom.Packaging
	} else {
	// Dependency type was not specified and we don't have the POM
	// for this artifact, use the default from Maven spec.
	d.Type = "jar"
	}
	}
	if d.Scope == "" {
	// Scope was not specified, use the default from Maven spec.
	d.Scope = "compile"
	}
	}
	}

	var mkTemplate = template.Must(template.New("mk").Parse(`
	include $(CLEAR_VARS)
	LOCAL_MODULE := {{.MkName}}
	LOCAL_MODULE_CLASS := JAVA_LIBRARIES
	LOCAL_UNINSTALLABLE_MODULE := true
	LOCAL_SRC_FILES := {{.ArtifactFile}}
	LOCAL_BUILT_MODULE_STEM := javalib.jar
	LOCAL_MODULE_SUFFIX := .{{.Packaging}}
	LOCAL_USE_AAPT2 := true
	LOCAL_SDK_VERSION := {{.SdkVersion}}
	LOCAL_STATIC_JAVA_LIBRARIES :={{range .MkJarDeps}} \
	{{.}}{{end}}
	LOCAL_STATIC_ANDROID_LIBRARIES :={{range .MkAarDeps}} \
	{{.}}{{end}}
	include $(BUILD_PREBUILT)
	`))

	var mkDepsTemplate = template.Must(template.New("mk").Parse(`
	include $(CLEAR_VARS)
	LOCAL_MODULE := {{.MkName}}-nodeps
	LOCAL_MODULE_CLASS := JAVA_LIBRARIES
	LOCAL_UNINSTALLABLE_MODULE := true
	LOCAL_SRC_FILES := {{.ArtifactFile}}
	LOCAL_BUILT_MODULE_STEM := javalib.jar
	LOCAL_MODULE_SUFFIX := .{{.Packaging}}
	LOCAL_USE_AAPT2 := true
	LOCAL_SDK_VERSION := {{.SdkVersion}}
	LOCAL_STATIC_ANDROID_LIBRARIES :={{range .MkAarDeps}} \
	{{.}}{{end}}
	include $(BUILD_PREBUILT)
	include $(CLEAR_VARS)
	LOCAL_MODULE := {{.MkName}}
	LOCAL_SDK_VERSION := {{.SdkVersion}}{{if .IsAar}}
	LOCAL_MANIFEST_FILE := manifests/{{.MkName}}/AndroidManifest.xml{{end}}
	LOCAL_STATIC_JAVA_LIBRARIES :={{if .IsJar}} \
	{{.MkName}}-nodeps{{end}}{{range .MkJarDeps}} \
	{{.}}{{end}}
	LOCAL_STATIC_ANDROID_LIBRARIES :={{if .IsAar}} \
	{{.MkName}}-nodeps{{end}}{{range .MkAarDeps}} \
	{{.}}{{end}}
	LOCAL_JAR_EXCLUDE_FILES := none
	LOCAL_JAVA_LANGUAGE_VERSION := 1.7
	LOCAL_USE_AAPT2 := true
	include $(BUILD_STATIC_JAVA_LIBRARY)
	`))

	func parse(filename string) (*Pom, error) {
	data, err := ioutil.ReadFile(filename)
	if err != nil {
	return nil, err
	}

	var pom Pom
	err = xml.Unmarshal(data, &pom)
	if err != nil {
	return nil, err
	}

	if useVersion != "" && pom.Version != useVersion {
	return nil, nil
	}

	if pom.Packaging == "" {
	pom.Packaging = "jar"
	}

	pom.PomFile = filename
	pom.ArtifactFile = strings.TrimSuffix(filename, ".pom") + "." + pom.Packaging

	return &pom, nil
	}

	func rerunForRegen(filename string) error {
	buf, err := ioutil.ReadFile(filename)
	if err != nil {
	return err
	}

	scanner := bufio.NewScanner(bytes.NewBuffer(buf))

	// Skip the first line in the file
	for i := 0; i < 2; i++ {
	if !scanner.Scan() {
	if scanner.Err() != nil {
	return scanner.Err()
	} else {
	return fmt.Errorf("unexpected EOF")
	}
	}
	}

	// Extract the old args from the file
	line := scanner.Text()
	if strings.HasPrefix(line, "# pom2mk ") {
	line = strings.TrimPrefix(line, "# pom2mk ")
	} else {
	return fmt.Errorf("unexpected second line: %q", line)
	}
	args := strings.Split(line, " ")
	lastArg := args[len(args)-1]
	args = args[:len(args)-1]

	// Append all current command line args except -regen <file> to the ones from the file
	for i := 1; i < len(os.Args); i++ {
	if os.Args[i] == "-regen" {
	i++
	} else {
	args = append(args, os.Args[i])
	}
	}
	args = append(args, lastArg)

	cmd := os.Args[0] + " " + strings.Join(args, " ")
	// Re-exec pom2mk with the new arguments
	output, err := exec.Command("/bin/sh", "-c", cmd).Output()
	if exitErr, _ := err.(*exec.ExitError); exitErr != nil {
	return fmt.Errorf("failed to run %s\n%s", cmd, string(exitErr.Stderr))
	} else if err != nil {
	return err
	}

	return ioutil.WriteFile(filename, output, 0666)
	}

	func main() {
	flag.Usage = func() {
	fmt.Fprintf(os.Stderr, `pom2mk, a tool to create Android.mk files from maven repos

	The tool will extract the necessary information from *.pom files to create an Android.mk whose
	aar libraries can be linked against when using AAPT2.

	Usage: %s [--rewrite <regex>=<replace>] [-exclude <module>] [--extra-deps <module>=<module>[,<module>]] [<dir>] [-regen <file>]

	-rewrite <regex>=<replace>
	rewrite can be used to specify mappings between Maven projects and Make modules. The -rewrite
	option can be specified multiple times. When determining the Make module for a given Maven
	project, mappings are searched in the order they were specified. The first <regex> matching
	either the Maven project's <groupId>:<artifactId> or <artifactId> will be used to generate
	the Make module name using <replace>. If no matches are found, <artifactId> is used.
	-exclude <module>
	Don't put the specified module in the makefile.
	-extra-deps <module>=<module>[,<module>]
	Some Android.mk modules have transitive dependencies that must be specified when they are
	depended upon (like android-support-v7-mediarouter requires android-support-v7-appcompat).
	This may be specified multiple times to declare these dependencies.
	-sdk-version <version>
	Sets LOCAL_SDK_VERSION := <version> for all modules.
	-use-version <version>
	If the maven directory contains multiple versions of artifacts and their pom files,
	-use-version can be used to only write makefiles for a specific version of those artifacts.
	-static-deps
	Whether to statically include direct dependencies.
	<dir>
	The directory to search for *.pom files under.
	The makefile is written to stdout, to be put in the current directory (often as Android.mk)
	-regen <file>
	Read arguments from <file> and overwrite it.
	`, os.Args[0])
	}

	var regen string

	flag.Var(&excludes, "exclude", "Exclude module")
	flag.Var(&extraDeps, "extra-deps", "Extra dependencies needed when depending on a module")
	flag.Var(&rewriteNames, "rewrite", "Regex(es) to rewrite artifact names")
	flag.StringVar(&sdkVersion, "sdk-version", "", "What to write to LOCAL_SDK_VERSION")
	flag.StringVar(&useVersion, "use-version", "", "Only read artifacts of a specific version")
	flag.BoolVar(&staticDeps, "static-deps", false, "Statically include direct dependencies")
	flag.StringVar(&regen, "regen", "", "Rewrite specified file")
	flag.Parse()

	if regen != "" {
	err := rerunForRegen(regen)
	if err != nil {
	fmt.Fprintln(os.Stderr, err)
	os.Exit(1)
	}
	os.Exit(0)
	}

	if flag.NArg() == 0 {
	fmt.Fprintln(os.Stderr, "Directory argument is required")
	os.Exit(1)
	} else if flag.NArg() > 1 {
	fmt.Fprintln(os.Stderr, "Multiple directories provided:", strings.Join(flag.Args(), " "))
	os.Exit(1)
	}

	dir := flag.Arg(0)
	absDir, err := filepath.Abs(dir)
	if err != nil {
	fmt.Fprintln(os.Stderr, "Failed to get absolute directory:", err)
	os.Exit(1)
	}

	var filenames []string
	err = filepath.Walk(absDir, func(path string, info os.FileInfo, err error) error {
	if err != nil {
	return err
	}

	name := info.Name()
	if info.IsDir() {
	if strings.HasPrefix(name, ".") {
	return filepath.SkipDir
	}
	return nil
	}

	if strings.HasPrefix(name, ".") {
	return nil
	}

	if strings.HasSuffix(name, ".pom") {
	path, err = filepath.Rel(absDir, path)
	if err != nil {
	return err
	}
	filenames = append(filenames, filepath.Join(dir, path))
	}
	return nil
	})
	if err != nil {
	fmt.Fprintln(os.Stderr, "Error walking files:", err)
	os.Exit(1)
	}

	if len(filenames) == 0 {
	fmt.Fprintln(os.Stderr, "Error: no *.pom files found under", dir)
	os.Exit(1)
	}

	sort.Strings(filenames)

	poms := []*Pom{}
	modules := make(map[string]*Pom)
	duplicate := false
	for _, filename := range filenames {
	pom, err := parse(filename)
	if err != nil {
	fmt.Fprintln(os.Stderr, "Error converting", filename, err)
	os.Exit(1)
	}

	if pom != nil {
	key := pom.MkName()
	if excludes[key] {
	continue
	}

	if old, ok := modules[key]; ok {
	fmt.Fprintln(os.Stderr, "Module", key, "defined twice:", old.PomFile, pom.PomFile)
	duplicate = true
	}

	poms = append(poms, pom)
	modules[key] = pom
	}
	}
	if duplicate {
	os.Exit(1)
	}

	for _, pom := range poms {
	pom.FixDeps(modules)
	}

	fmt.Println("# Automatically generated with:")
	fmt.Println("# pom2mk", strings.Join(proptools.ShellEscape(os.Args[1:]), " "))
	fmt.Println("LOCAL_PATH := $(call my-dir)")

	for _, pom := range poms {
	var err error
	if staticDeps {
	err = mkDepsTemplate.Execute(os.Stdout, pom)
	} else {
	err = mkTemplate.Execute(os.Stdout, pom)
	}
	if err != nil {
	fmt.Fprintln(os.Stderr, "Error writing", pom.PomFile, pom.MkName(), err)
	os.Exit(1)
	}
	}
	}