packages/flutter_tools/lib/src/android/android_sdk.dart - mirrors/flutter - Git at Google

 // Copyright 2014 The Flutter Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 import '../base/common.dart';
 import '../base/config.dart';
 import '../base/file_system.dart';
 import '../base/platform.dart';
 import '../base/process.dart';
 import '../base/version.dart';
 import '../convert.dart';
 import '../globals.dart' as globals;
 import 'java.dart';

 // ANDROID_SDK_ROOT is deprecated.
 // See https://developer.android.com/studio/command-line/variables.html#envar
 const String kAndroidSdkRoot = 'ANDROID_SDK_ROOT';
 const String kAndroidHome = 'ANDROID_HOME';

 // No official environment variable for the NDK root is documented:
 // https://developer.android.com/tools/variables#envar
 // The follow three seem to be most commonly used.
 const String kAndroidNdkHome = 'ANDROID_NDK_HOME';
 const String kAndroidNdkPath = 'ANDROID_NDK_PATH';
 const String kAndroidNdkRoot = 'ANDROID_NDK_ROOT';

 final RegExp _numberedAndroidPlatformRe = RegExp(r'^android-([0-9]+)$');
 final RegExp _sdkVersionRe = RegExp(r'^ro.build.version.sdk=([0-9]+)$');

 // Android SDK layout:

 // $ANDROID_HOME/platform-tools/adb

 // $ANDROID_HOME/build-tools/19.1.0/aapt, dx, zipalign
 // $ANDROID_HOME/build-tools/22.0.1/aapt
 // $ANDROID_HOME/build-tools/23.0.2/aapt
 // $ANDROID_HOME/build-tools/24.0.0-preview/aapt
 // $ANDROID_HOME/build-tools/25.0.2/apksigner

 // $ANDROID_HOME/platforms/android-22/android.jar
 // $ANDROID_HOME/platforms/android-23/android.jar
 // $ANDROID_HOME/platforms/android-N/android.jar
 class AndroidSdk {
   AndroidSdk(this.directory, {
     Java? java,
     FileSystem? fileSystem,
   }): _java = java {
     reinitialize(fileSystem: fileSystem);
   }

   /// The Android SDK root directory.
   final Directory directory;

   final Java? _java;

   List<AndroidSdkVersion> _sdkVersions = <AndroidSdkVersion>[];
   AndroidSdkVersion? _latestVersion;

   /// Whether the `cmdline-tools` directory exists in the Android SDK.
   ///
   /// This is required to use the newest SDK manager which only works with
   /// the newer JDK.
   bool get cmdlineToolsAvailable => directory.childDirectory('cmdline-tools').existsSync();

   /// Whether the `platform-tools` or `cmdline-tools` directory exists in the Android SDK.
   ///
   /// It is possible to have an Android SDK folder that is missing this with
   /// the expectation that it will be downloaded later, e.g. by gradle or the
   /// sdkmanager. The [licensesAvailable] property should be used to determine
   /// whether the licenses are at least possibly accepted.
   bool get platformToolsAvailable => cmdlineToolsAvailable
      || directory.childDirectory('platform-tools').existsSync();

   /// Whether the `licenses` directory exists in the Android SDK.
   ///
   /// The existence of this folder normally indicates that the SDK licenses have
   /// been accepted, e.g. via the sdkmanager, Android Studio, or by copying them
   /// from another workstation such as in CI scenarios. If these files are valid
   /// gradle or the sdkmanager will be able to download and use other parts of
   /// the SDK on demand.
   bool get licensesAvailable => directory.childDirectory('licenses').existsSync();

   static AndroidSdk? locateAndroidSdk() {
     String? findAndroidHomeDir() {
       String? androidHomeDir;
       if (globals.config.containsKey('android-sdk')) {
         androidHomeDir = globals.config.getValue('android-sdk') as String?;
       } else if (globals.platform.environment.containsKey(kAndroidHome)) {
         androidHomeDir = globals.platform.environment[kAndroidHome];
       } else if (globals.platform.environment.containsKey(kAndroidSdkRoot)) {
         androidHomeDir = globals.platform.environment[kAndroidSdkRoot];
       } else if (globals.platform.isLinux) {
         if (globals.fsUtils.homeDirPath != null) {
           androidHomeDir = globals.fs.path.join(
             globals.fsUtils.homeDirPath!,
             'Android',
             'Sdk',
           );
         }
       } else if (globals.platform.isMacOS) {
         if (globals.fsUtils.homeDirPath != null) {
           androidHomeDir = globals.fs.path.join(
             globals.fsUtils.homeDirPath!,
             'Library',
             'Android',
             'sdk',
           );
         }
       } else if (globals.platform.isWindows) {
         if (globals.fsUtils.homeDirPath != null) {
           androidHomeDir = globals.fs.path.join(
             globals.fsUtils.homeDirPath!,
             'AppData',
             'Local',
             'Android',
             'sdk',
           );
         }
       }

       if (androidHomeDir != null) {
         if (validSdkDirectory(androidHomeDir)) {
           return androidHomeDir;
         }
         if (validSdkDirectory(globals.fs.path.join(androidHomeDir, 'sdk'))) {
           return globals.fs.path.join(androidHomeDir, 'sdk');
         }
       }

       // in build-tools/$version/aapt
       final List<File> aaptBins = globals.os.whichAll('aapt');
       for (File aaptBin in aaptBins) {
         // Make sure we're using the aapt from the SDK.
         aaptBin = globals.fs.file(aaptBin.resolveSymbolicLinksSync());
         final String dir = aaptBin.parent.parent.parent.path;
         if (validSdkDirectory(dir)) {
           return dir;
         }
       }

       // in platform-tools/adb
       final List<File> adbBins = globals.os.whichAll('adb');
       for (File adbBin in adbBins) {
         // Make sure we're using the adb from the SDK.
         adbBin = globals.fs.file(adbBin.resolveSymbolicLinksSync());
         final String dir = adbBin.parent.parent.path;
         if (validSdkDirectory(dir)) {
           return dir;
         }
       }

       return null;
     }

     final String? androidHomeDir = findAndroidHomeDir();
     if (androidHomeDir == null) {
       // No dice.
       globals.printTrace('Unable to locate an Android SDK.');
       return null;
     }

     return AndroidSdk(globals.fs.directory(androidHomeDir));
   }

   static bool validSdkDirectory(String dir) {
     return sdkDirectoryHasLicenses(dir) || sdkDirectoryHasPlatformTools(dir);
   }

   static bool sdkDirectoryHasPlatformTools(String dir) {
     return globals.fs.isDirectorySync(globals.fs.path.join(dir, 'platform-tools'));
   }

   static bool sdkDirectoryHasLicenses(String dir) {
     return globals.fs.isDirectorySync(globals.fs.path.join(dir, 'licenses'));
   }

   List<AndroidSdkVersion> get sdkVersions => _sdkVersions;

   AndroidSdkVersion? get latestVersion => _latestVersion;

   late final String? adbPath = getPlatformToolsPath(globals.platform.isWindows ? 'adb.exe' : 'adb');

   String? get emulatorPath => getEmulatorPath();

   String? get avdManagerPath => getAvdManagerPath();

   /// Locate the path for storing AVD emulator images. Returns null if none found.
   String? getAvdPath() {
     final String? avdHome = globals.platform.environment['ANDROID_AVD_HOME'];
     final String? home = globals.platform.environment['HOME'];
     final List<String> searchPaths = <String>[
       if (avdHome != null)
         avdHome,
       if (home != null)
         globals.fs.path.join(home, '.android', 'avd'),
     ];

     if (globals.platform.isWindows) {
       final String? homeDrive = globals.platform.environment['HOMEDRIVE'];
       final String? homePath = globals.platform.environment['HOMEPATH'];

       if (homeDrive != null && homePath != null) {
         // Can't use path.join for HOMEDRIVE/HOMEPATH
         // https://github.com/dart-lang/path/issues/37
         final String home = homeDrive + homePath;
         searchPaths.add(globals.fs.path.join(home, '.android', 'avd'));
       }
     }

     for (final String searchPath in searchPaths) {
       if (globals.fs.directory(searchPath).existsSync()) {
         return searchPath;
       }
     }
     return null;
   }

   Directory get _platformsDir => directory.childDirectory('platforms');

   Iterable<Directory> get _platforms {
     Iterable<Directory> platforms = <Directory>[];
     if (_platformsDir.existsSync()) {
       platforms = _platformsDir
         .listSync()
         .whereType<Directory>();
     }
     return platforms;
   }

   /// Validate the Android SDK. This returns an empty list if there are no
   /// issues; otherwise, it returns a list of issues found.
   List<String> validateSdkWellFormed() {
     if (adbPath == null || !globals.processManager.canRun(adbPath)) {
       return <String>['Android SDK file not found: ${adbPath ?? 'adb'}.'];
     }

     if (sdkVersions.isEmpty || latestVersion == null) {
       final StringBuffer msg = StringBuffer('No valid Android SDK platforms found in ${_platformsDir.path}.');
       if (_platforms.isEmpty) {
         msg.write(' Directory was empty.');
       } else {
         msg.write(' Candidates were:\n');
         msg.write(_platforms
           .map((Directory dir) => '  - ${dir.basename}')
           .join('\n'));
       }
       return <String>[msg.toString()];
     }

     return latestVersion!.validateSdkWellFormed();
   }

   String? getPlatformToolsPath(String binaryName) {
     final File cmdlineToolsBinary = directory.childDirectory('cmdline-tools').childFile(binaryName);
     if (cmdlineToolsBinary.existsSync()) {
       return cmdlineToolsBinary.path;
     }
     final File platformToolBinary = directory.childDirectory('platform-tools').childFile(binaryName);
     if (platformToolBinary.existsSync()) {
       return platformToolBinary.path;
     }
     return null;
   }

   String? getEmulatorPath() {
     final String binaryName = globals.platform.isWindows ? 'emulator.exe' : 'emulator';
     // Emulator now lives inside "emulator" but used to live inside "tools" so
     // try both.
     final List<String> searchFolders = <String>['emulator', 'tools'];
     for (final String folder in searchFolders) {
       final File file = directory.childDirectory(folder).childFile(binaryName);
       if (file.existsSync()) {
         return file.path;
       }
     }
     return null;
   }

   String? getCmdlineToolsPath(String binaryName, {bool skipOldTools = false}) {
     // First look for the latest version of the command-line tools
     final File cmdlineToolsLatestBinary = directory
       .childDirectory('cmdline-tools')
       .childDirectory('latest')
       .childDirectory('bin')
       .childFile(binaryName);
     if (cmdlineToolsLatestBinary.existsSync()) {
       return cmdlineToolsLatestBinary.path;
     }

     // Next look for the highest version of the command-line tools
     final Directory cmdlineToolsDir = directory.childDirectory('cmdline-tools');
     if (cmdlineToolsDir.existsSync()) {
       final List<Version> cmdlineTools = cmdlineToolsDir
         .listSync()
         .whereType<Directory>()
         .map((Directory subDirectory) {
           try {
             return Version.parse(subDirectory.basename);
           } on Exception {
             return null;
           }
         })
         .whereType<Version>()
         .toList();
       cmdlineTools.sort();

       for (final Version cmdlineToolsVersion in cmdlineTools.reversed) {
         final File cmdlineToolsBinary = directory
           .childDirectory('cmdline-tools')
           .childDirectory(cmdlineToolsVersion.toString())
           .childDirectory('bin')
           .childFile(binaryName);
         if (cmdlineToolsBinary.existsSync()) {
           return cmdlineToolsBinary.path;
         }
       }
     }
     if (skipOldTools) {
       return null;
     }

     // Finally fallback to the old SDK tools
     final File toolsBinary = directory.childDirectory('tools').childDirectory('bin').childFile(binaryName);
     if (toolsBinary.existsSync()) {
       return toolsBinary.path;
     }

     return null;
   }

   String? getAvdManagerPath() => getCmdlineToolsPath(globals.platform.isWindows ? 'avdmanager.bat' : 'avdmanager');

   /// From https://developer.android.com/ndk/guides/other_build_systems.
   static const Map<String, String> _llvmHostDirectoryName = <String, String>{
     'macos': 'darwin-x86_64',
     'linux': 'linux-x86_64',
     'windows': 'windows-x86_64',
   };

   /// Locates the binary path for an NDK binary.
   ///
   /// The order of resolution is as follows:
   ///
   /// 1. If [globals.config] defines an `'android-ndk'` use that.
   /// 2. If the environment variable `ANDROID_NDK_HOME` is defined, use that.
   /// 3. If the environment variable `ANDROID_NDK_PATH` is defined, use that.
   /// 4. If the environment variable `ANDROID_NDK_ROOT` is defined, use that.
   /// 5. Look for the default install location inside the Android SDK:
   ///    [directory]/ndk/\<version\>/. If multiple versions exist, use the
   ///    newest.
   String? getNdkBinaryPath(
     String binaryName, {
     Platform? platform,
     Config? config,
   }) {
     platform ??= globals.platform;
     config ??= globals.config;
     Directory? findAndroidNdkHomeDir() {
       String? androidNdkHomeDir;
       if (config!.containsKey('android-ndk')) {
         androidNdkHomeDir = config.getValue('android-ndk') as String?;
       } else if (platform!.environment.containsKey(kAndroidNdkHome)) {
         androidNdkHomeDir = platform.environment[kAndroidNdkHome];
       } else if (platform.environment.containsKey(kAndroidNdkPath)) {
         androidNdkHomeDir = platform.environment[kAndroidNdkPath];
       } else if (platform.environment.containsKey(kAndroidNdkRoot)) {
         androidNdkHomeDir = platform.environment[kAndroidNdkRoot];
       }
       if (androidNdkHomeDir != null) {
         return directory.fileSystem.directory(androidNdkHomeDir);
       }

       // Look for the default install location of the NDK inside the Android
       // SDK when installed through `sdkmanager` or Android studio.
       final Directory ndk = directory.childDirectory('ndk');
       if (!ndk.existsSync()) {
         return null;
       }
       final List<Version> ndkVersions = ndk
           .listSync()
           .map((FileSystemEntity entity) {
             try {
               return Version.parse(entity.basename);
             } on Exception {
               return null;
             }
           })
           .whereType<Version>()
           .toList()
         // Use latest NDK first.
         ..sort((Version a, Version b) => -a.compareTo(b));
       if (ndkVersions.isEmpty) {
         return null;
       }
       return ndk.childDirectory(ndkVersions.first.toString());
     }

     final Directory? androidNdkHomeDir = findAndroidNdkHomeDir();
     if (androidNdkHomeDir == null) {
       return null;
     }
     final File executable = androidNdkHomeDir
         .childDirectory('toolchains')
         .childDirectory('llvm')
         .childDirectory('prebuilt')
         .childDirectory(_llvmHostDirectoryName[platform.operatingSystem]!)
         .childDirectory('bin')
         .childFile(binaryName);
     if (executable.existsSync()) {
       // LLVM missing in this NDK version.
       return executable.path;
     }
     return null;
   }

   String? getNdkClangPath({Platform? platform, Config? config}) {
     platform ??= globals.platform;
     return getNdkBinaryPath(
       platform.isWindows ? 'clang.exe' : 'clang',
       platform: platform,
       config: config,
     );
   }

   String? getNdkArPath({Platform? platform, Config? config}) {
     platform ??= globals.platform;
     return getNdkBinaryPath(
       platform.isWindows ? 'llvm-ar.exe' : 'llvm-ar',
       platform: platform,
       config: config,
     );
   }

   String? getNdkLdPath({Platform? platform, Config? config}) {
     platform ??= globals.platform;
     return getNdkBinaryPath(
       platform.isWindows ? 'ld.lld.exe' : 'ld.lld',
       platform: platform,
       config: config,
     );
   }

   /// Sets up various paths used internally.
   ///
   /// This method should be called in a case where the tooling may have updated
   /// SDK artifacts, such as after running a gradle build.
   void reinitialize({FileSystem? fileSystem}) {
     List<Version> buildTools = <Version>[]; // 19.1.0, 22.0.1, ...

     final Directory buildToolsDir = directory.childDirectory('build-tools');
     if (buildToolsDir.existsSync()) {
       buildTools = buildToolsDir
         .listSync()
         .map((FileSystemEntity entity) {
           try {
             return Version.parse(entity.basename);
           } on Exception {
             return null;
           }
         })
         .whereType<Version>()
         .toList();
     }

     // Match up platforms with the best corresponding build-tools.
     _sdkVersions = _platforms.map<AndroidSdkVersion?>((Directory platformDir) {
       final String platformName = platformDir.basename;
       int platformVersion;

       try {
         final Match? numberedVersion = _numberedAndroidPlatformRe.firstMatch(platformName);
         if (numberedVersion != null) {
           platformVersion = int.parse(numberedVersion.group(1)!);
         } else {
           final String buildProps = platformDir.childFile('build.prop').readAsStringSync();
           final Iterable<Match> versionMatches = const LineSplitter()
               .convert(buildProps)
               .map<RegExpMatch?>(_sdkVersionRe.firstMatch)
               .whereType<Match>();

           if (versionMatches.isEmpty) {
             return null;
           }

           final String? versionString = versionMatches.first.group(1);
           if (versionString == null) {
             return null;
           }
           platformVersion = int.parse(versionString);
         }
       } on Exception {
         return null;
       }

       Version? buildToolsVersion = Version.primary(buildTools.where((Version version) {
         return version.major == platformVersion;
       }).toList());

       buildToolsVersion ??= Version.primary(buildTools);

       if (buildToolsVersion == null) {
         return null;
       }

       return AndroidSdkVersion._(
         this,
         sdkLevel: platformVersion,
         platformName: platformName,
         buildToolsVersion: buildToolsVersion,
         fileSystem: fileSystem ?? globals.fs,
       );
     }).whereType<AndroidSdkVersion>().toList();

     _sdkVersions.sort();

     _latestVersion = _sdkVersions.isEmpty ? null : _sdkVersions.last;
   }

   /// Returns the filesystem path of the Android SDK manager tool.
   String? get sdkManagerPath {
     final String executable = globals.platform.isWindows
       ? 'sdkmanager.bat'
       : 'sdkmanager';
     final String? path = getCmdlineToolsPath(executable, skipOldTools: true);
     if (path != null) {
       return path;
     }
     return null;
   }

   /// Returns the version of the Android SDK manager tool or null if not found.
   String? get sdkManagerVersion {
     if (sdkManagerPath == null || !globals.processManager.canRun(sdkManagerPath)) {
       throwToolExit(
         'Android sdkmanager not found. Update to the latest Android SDK and ensure that '
         'the cmdline-tools are installed to resolve this.'
       );
     }
     final RunResult result = globals.processUtils.runSync(
       <String>[sdkManagerPath!, '--version'],
       environment: _java?.environment,
     );
     if (result.exitCode != 0) {
       globals.printTrace('sdkmanager --version failed: exitCode: ${result.exitCode} stdout: ${result.stdout} stderr: ${result.stderr}');
       return null;
     }
     return result.stdout.trim();
   }

   @override
   String toString() => 'AndroidSdk: $directory';
 }

 class AndroidSdkVersion implements Comparable<AndroidSdkVersion> {
   AndroidSdkVersion._(
     this.sdk, {
     required this.sdkLevel,
     required this.platformName,
     required this.buildToolsVersion,
     required FileSystem fileSystem,
   }) : _fileSystem = fileSystem;

   final AndroidSdk sdk;
   final int sdkLevel;
   final String platformName;
   final Version buildToolsVersion;

   final FileSystem _fileSystem;

   String get buildToolsVersionName => buildToolsVersion.toString();

   String get androidJarPath => getPlatformsPath('android.jar');

   /// Return the path to the android application package tool.
   ///
   /// This is used to dump the xml in order to launch built android applications.
   ///
   /// See also:
   ///   * [AndroidApk.fromApk], which depends on this to determine application identifiers.
   String get aaptPath => getBuildToolsPath('aapt');

   List<String> validateSdkWellFormed() {
     final String? existsAndroidJarPath = _exists(androidJarPath);
     if (existsAndroidJarPath != null) {
       return <String>[existsAndroidJarPath];
     }

     final String? canRunAaptPath = _canRun(aaptPath);
     if (canRunAaptPath != null) {
       return <String>[canRunAaptPath];
     }

     return <String>[];
   }

   String getPlatformsPath(String itemName) {
     return sdk.directory.childDirectory('platforms').childDirectory(platformName).childFile(itemName).path;
   }

   String getBuildToolsPath(String binaryName) {
     return sdk.directory.childDirectory('build-tools').childDirectory(buildToolsVersionName).childFile(binaryName).path;
   }

   @override
   int compareTo(AndroidSdkVersion other) => sdkLevel - other.sdkLevel;

   @override
   String toString() => '[${sdk.directory}, SDK version $sdkLevel, build-tools $buildToolsVersionName]';

   String? _exists(String path) {
     if (!_fileSystem.isFileSync(path)) {
       return 'Android SDK file not found: $path.';
     }
     return null;
   }

   String? _canRun(String path) {
     if (!globals.processManager.canRun(path)) {
       return 'Android SDK file not found: $path.';
     }
     return null;
   }
 }
	// Copyright 2014 The Flutter Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	import '../base/common.dart';
	import '../base/config.dart';
	import '../base/file_system.dart';
	import '../base/platform.dart';
	import '../base/process.dart';
	import '../base/version.dart';
	import '../convert.dart';
	import '../globals.dart' as globals;
	import 'java.dart';

	// ANDROID_SDK_ROOT is deprecated.
	// See https://developer.android.com/studio/command-line/variables.html#envar
	const String kAndroidSdkRoot = 'ANDROID_SDK_ROOT';
	const String kAndroidHome = 'ANDROID_HOME';

	// No official environment variable for the NDK root is documented:
	// https://developer.android.com/tools/variables#envar
	// The follow three seem to be most commonly used.
	const String kAndroidNdkHome = 'ANDROID_NDK_HOME';
	const String kAndroidNdkPath = 'ANDROID_NDK_PATH';
	const String kAndroidNdkRoot = 'ANDROID_NDK_ROOT';

	final RegExp _numberedAndroidPlatformRe = RegExp(r'^android-([0-9]+)$');
	final RegExp _sdkVersionRe = RegExp(r'^ro.build.version.sdk=([0-9]+)$');

	// Android SDK layout:

	// $ANDROID_HOME/platform-tools/adb

	// $ANDROID_HOME/build-tools/19.1.0/aapt, dx, zipalign
	// $ANDROID_HOME/build-tools/22.0.1/aapt
	// $ANDROID_HOME/build-tools/23.0.2/aapt
	// $ANDROID_HOME/build-tools/24.0.0-preview/aapt
	// $ANDROID_HOME/build-tools/25.0.2/apksigner

	// $ANDROID_HOME/platforms/android-22/android.jar
	// $ANDROID_HOME/platforms/android-23/android.jar
	// $ANDROID_HOME/platforms/android-N/android.jar
	class AndroidSdk {
	AndroidSdk(this.directory, {
	Java? java,
	FileSystem? fileSystem,
	}): _java = java {
	reinitialize(fileSystem: fileSystem);
	}

	/// The Android SDK root directory.
	final Directory directory;

	final Java? _java;

	List<AndroidSdkVersion> _sdkVersions = <AndroidSdkVersion>[];
	AndroidSdkVersion? _latestVersion;

	/// Whether the `cmdline-tools` directory exists in the Android SDK.
	///
	/// This is required to use the newest SDK manager which only works with
	/// the newer JDK.
	bool get cmdlineToolsAvailable => directory.childDirectory('cmdline-tools').existsSync();

	/// Whether the `platform-tools` or `cmdline-tools` directory exists in the Android SDK.
	///
	/// It is possible to have an Android SDK folder that is missing this with
	/// the expectation that it will be downloaded later, e.g. by gradle or the
	/// sdkmanager. The [licensesAvailable] property should be used to determine
	/// whether the licenses are at least possibly accepted.
	bool get platformToolsAvailable => cmdlineToolsAvailable
	\|\| directory.childDirectory('platform-tools').existsSync();

	/// Whether the `licenses` directory exists in the Android SDK.
	///
	/// The existence of this folder normally indicates that the SDK licenses have
	/// been accepted, e.g. via the sdkmanager, Android Studio, or by copying them
	/// from another workstation such as in CI scenarios. If these files are valid
	/// gradle or the sdkmanager will be able to download and use other parts of
	/// the SDK on demand.
	bool get licensesAvailable => directory.childDirectory('licenses').existsSync();

	static AndroidSdk? locateAndroidSdk() {
	String? findAndroidHomeDir() {
	String? androidHomeDir;
	if (globals.config.containsKey('android-sdk')) {
	androidHomeDir = globals.config.getValue('android-sdk') as String?;
	} else if (globals.platform.environment.containsKey(kAndroidHome)) {
	androidHomeDir = globals.platform.environment[kAndroidHome];
	} else if (globals.platform.environment.containsKey(kAndroidSdkRoot)) {
	androidHomeDir = globals.platform.environment[kAndroidSdkRoot];
	} else if (globals.platform.isLinux) {
	if (globals.fsUtils.homeDirPath != null) {
	androidHomeDir = globals.fs.path.join(
	globals.fsUtils.homeDirPath!,
	'Android',
	'Sdk',
	);
	}
	} else if (globals.platform.isMacOS) {
	if (globals.fsUtils.homeDirPath != null) {
	androidHomeDir = globals.fs.path.join(
	globals.fsUtils.homeDirPath!,
	'Library',
	'Android',
	'sdk',
	);
	}
	} else if (globals.platform.isWindows) {
	if (globals.fsUtils.homeDirPath != null) {
	androidHomeDir = globals.fs.path.join(
	globals.fsUtils.homeDirPath!,
	'AppData',
	'Local',
	'Android',
	'sdk',
	);
	}
	}

	if (androidHomeDir != null) {
	if (validSdkDirectory(androidHomeDir)) {
	return androidHomeDir;
	}
	if (validSdkDirectory(globals.fs.path.join(androidHomeDir, 'sdk'))) {
	return globals.fs.path.join(androidHomeDir, 'sdk');
	}
	}

	// in build-tools/$version/aapt
	final List<File> aaptBins = globals.os.whichAll('aapt');
	for (File aaptBin in aaptBins) {
	// Make sure we're using the aapt from the SDK.
	aaptBin = globals.fs.file(aaptBin.resolveSymbolicLinksSync());
	final String dir = aaptBin.parent.parent.parent.path;
	if (validSdkDirectory(dir)) {
	return dir;
	}
	}

	// in platform-tools/adb
	final List<File> adbBins = globals.os.whichAll('adb');
	for (File adbBin in adbBins) {
	// Make sure we're using the adb from the SDK.
	adbBin = globals.fs.file(adbBin.resolveSymbolicLinksSync());
	final String dir = adbBin.parent.parent.path;
	if (validSdkDirectory(dir)) {
	return dir;
	}
	}

	return null;
	}

	final String? androidHomeDir = findAndroidHomeDir();
	if (androidHomeDir == null) {
	// No dice.
	globals.printTrace('Unable to locate an Android SDK.');
	return null;
	}

	return AndroidSdk(globals.fs.directory(androidHomeDir));
	}

	static bool validSdkDirectory(String dir) {
	return sdkDirectoryHasLicenses(dir) \|\| sdkDirectoryHasPlatformTools(dir);
	}

	static bool sdkDirectoryHasPlatformTools(String dir) {
	return globals.fs.isDirectorySync(globals.fs.path.join(dir, 'platform-tools'));
	}

	static bool sdkDirectoryHasLicenses(String dir) {
	return globals.fs.isDirectorySync(globals.fs.path.join(dir, 'licenses'));
	}

	List<AndroidSdkVersion> get sdkVersions => _sdkVersions;

	AndroidSdkVersion? get latestVersion => _latestVersion;

	late final String? adbPath = getPlatformToolsPath(globals.platform.isWindows ? 'adb.exe' : 'adb');

	String? get emulatorPath => getEmulatorPath();

	String? get avdManagerPath => getAvdManagerPath();

	/// Locate the path for storing AVD emulator images. Returns null if none found.
	String? getAvdPath() {
	final String? avdHome = globals.platform.environment['ANDROID_AVD_HOME'];
	final String? home = globals.platform.environment['HOME'];
	final List<String> searchPaths = <String>[
	if (avdHome != null)
	avdHome,
	if (home != null)
	globals.fs.path.join(home, '.android', 'avd'),
	];

	if (globals.platform.isWindows) {
	final String? homeDrive = globals.platform.environment['HOMEDRIVE'];
	final String? homePath = globals.platform.environment['HOMEPATH'];

	if (homeDrive != null && homePath != null) {
	// Can't use path.join for HOMEDRIVE/HOMEPATH
	// https://github.com/dart-lang/path/issues/37
	final String home = homeDrive + homePath;
	searchPaths.add(globals.fs.path.join(home, '.android', 'avd'));
	}
	}

	for (final String searchPath in searchPaths) {
	if (globals.fs.directory(searchPath).existsSync()) {
	return searchPath;
	}
	}
	return null;
	}

	Directory get _platformsDir => directory.childDirectory('platforms');

	Iterable<Directory> get _platforms {
	Iterable<Directory> platforms = <Directory>[];
	if (_platformsDir.existsSync()) {
	platforms = _platformsDir
	.listSync()
	.whereType<Directory>();
	}
	return platforms;
	}

	/// Validate the Android SDK. This returns an empty list if there are no
	/// issues; otherwise, it returns a list of issues found.
	List<String> validateSdkWellFormed() {
	if (adbPath == null \|\| !globals.processManager.canRun(adbPath)) {
	return <String>['Android SDK file not found: ${adbPath ?? 'adb'}.'];
	}

	if (sdkVersions.isEmpty \|\| latestVersion == null) {
	final StringBuffer msg = StringBuffer('No valid Android SDK platforms found in ${_platformsDir.path}.');
	if (_platforms.isEmpty) {
	msg.write(' Directory was empty.');
	} else {
	msg.write(' Candidates were:\n');
	msg.write(_platforms
	.map((Directory dir) => ' - ${dir.basename}')
	.join('\n'));
	}
	return <String>[msg.toString()];
	}

	return latestVersion!.validateSdkWellFormed();
	}

	String? getPlatformToolsPath(String binaryName) {
	final File cmdlineToolsBinary = directory.childDirectory('cmdline-tools').childFile(binaryName);
	if (cmdlineToolsBinary.existsSync()) {
	return cmdlineToolsBinary.path;
	}
	final File platformToolBinary = directory.childDirectory('platform-tools').childFile(binaryName);
	if (platformToolBinary.existsSync()) {
	return platformToolBinary.path;
	}
	return null;
	}

	String? getEmulatorPath() {
	final String binaryName = globals.platform.isWindows ? 'emulator.exe' : 'emulator';
	// Emulator now lives inside "emulator" but used to live inside "tools" so
	// try both.
	final List<String> searchFolders = <String>['emulator', 'tools'];
	for (final String folder in searchFolders) {
	final File file = directory.childDirectory(folder).childFile(binaryName);
	if (file.existsSync()) {
	return file.path;
	}
	}
	return null;
	}

	String? getCmdlineToolsPath(String binaryName, {bool skipOldTools = false}) {
	// First look for the latest version of the command-line tools
	final File cmdlineToolsLatestBinary = directory
	.childDirectory('cmdline-tools')
	.childDirectory('latest')
	.childDirectory('bin')
	.childFile(binaryName);
	if (cmdlineToolsLatestBinary.existsSync()) {
	return cmdlineToolsLatestBinary.path;
	}

	// Next look for the highest version of the command-line tools
	final Directory cmdlineToolsDir = directory.childDirectory('cmdline-tools');
	if (cmdlineToolsDir.existsSync()) {
	final List<Version> cmdlineTools = cmdlineToolsDir
	.listSync()
	.whereType<Directory>()
	.map((Directory subDirectory) {
	try {
	return Version.parse(subDirectory.basename);
	} on Exception {
	return null;
	}
	})
	.whereType<Version>()
	.toList();
	cmdlineTools.sort();

	for (final Version cmdlineToolsVersion in cmdlineTools.reversed) {
	final File cmdlineToolsBinary = directory
	.childDirectory('cmdline-tools')
	.childDirectory(cmdlineToolsVersion.toString())
	.childDirectory('bin')
	.childFile(binaryName);
	if (cmdlineToolsBinary.existsSync()) {
	return cmdlineToolsBinary.path;
	}
	}
	}
	if (skipOldTools) {
	return null;
	}

	// Finally fallback to the old SDK tools
	final File toolsBinary = directory.childDirectory('tools').childDirectory('bin').childFile(binaryName);
	if (toolsBinary.existsSync()) {
	return toolsBinary.path;
	}

	return null;
	}

	String? getAvdManagerPath() => getCmdlineToolsPath(globals.platform.isWindows ? 'avdmanager.bat' : 'avdmanager');

	/// From https://developer.android.com/ndk/guides/other_build_systems.
	static const Map<String, String> _llvmHostDirectoryName = <String, String>{
	'macos': 'darwin-x86_64',
	'linux': 'linux-x86_64',
	'windows': 'windows-x86_64',
	};

	/// Locates the binary path for an NDK binary.
	///
	/// The order of resolution is as follows:
	///
	/// 1. If [globals.config] defines an `'android-ndk'` use that.
	/// 2. If the environment variable `ANDROID_NDK_HOME` is defined, use that.
	/// 3. If the environment variable `ANDROID_NDK_PATH` is defined, use that.
	/// 4. If the environment variable `ANDROID_NDK_ROOT` is defined, use that.
	/// 5. Look for the default install location inside the Android SDK:
	/// [directory]/ndk/\<version\>/. If multiple versions exist, use the
	/// newest.
	String? getNdkBinaryPath(
	String binaryName, {
	Platform? platform,
	Config? config,
	}) {
	platform ??= globals.platform;
	config ??= globals.config;
	Directory? findAndroidNdkHomeDir() {
	String? androidNdkHomeDir;
	if (config!.containsKey('android-ndk')) {
	androidNdkHomeDir = config.getValue('android-ndk') as String?;
	} else if (platform!.environment.containsKey(kAndroidNdkHome)) {
	androidNdkHomeDir = platform.environment[kAndroidNdkHome];
	} else if (platform.environment.containsKey(kAndroidNdkPath)) {
	androidNdkHomeDir = platform.environment[kAndroidNdkPath];
	} else if (platform.environment.containsKey(kAndroidNdkRoot)) {
	androidNdkHomeDir = platform.environment[kAndroidNdkRoot];
	}
	if (androidNdkHomeDir != null) {
	return directory.fileSystem.directory(androidNdkHomeDir);
	}

	// Look for the default install location of the NDK inside the Android
	// SDK when installed through `sdkmanager` or Android studio.
	final Directory ndk = directory.childDirectory('ndk');
	if (!ndk.existsSync()) {
	return null;
	}
	final List<Version> ndkVersions = ndk
	.listSync()
	.map((FileSystemEntity entity) {
	try {
	return Version.parse(entity.basename);
	} on Exception {
	return null;
	}
	})
	.whereType<Version>()
	.toList()
	// Use latest NDK first.
	..sort((Version a, Version b) => -a.compareTo(b));
	if (ndkVersions.isEmpty) {
	return null;
	}
	return ndk.childDirectory(ndkVersions.first.toString());
	}

	final Directory? androidNdkHomeDir = findAndroidNdkHomeDir();
	if (androidNdkHomeDir == null) {
	return null;
	}
	final File executable = androidNdkHomeDir
	.childDirectory('toolchains')
	.childDirectory('llvm')
	.childDirectory('prebuilt')
	.childDirectory(_llvmHostDirectoryName[platform.operatingSystem]!)
	.childDirectory('bin')
	.childFile(binaryName);
	if (executable.existsSync()) {
	// LLVM missing in this NDK version.
	return executable.path;
	}
	return null;
	}

	String? getNdkClangPath({Platform? platform, Config? config}) {
	platform ??= globals.platform;
	return getNdkBinaryPath(
	platform.isWindows ? 'clang.exe' : 'clang',
	platform: platform,
	config: config,
	);
	}

	String? getNdkArPath({Platform? platform, Config? config}) {
	platform ??= globals.platform;
	return getNdkBinaryPath(
	platform.isWindows ? 'llvm-ar.exe' : 'llvm-ar',
	platform: platform,
	config: config,
	);
	}

	String? getNdkLdPath({Platform? platform, Config? config}) {
	platform ??= globals.platform;
	return getNdkBinaryPath(
	platform.isWindows ? 'ld.lld.exe' : 'ld.lld',
	platform: platform,
	config: config,
	);
	}

	/// Sets up various paths used internally.
	///
	/// This method should be called in a case where the tooling may have updated
	/// SDK artifacts, such as after running a gradle build.
	void reinitialize({FileSystem? fileSystem}) {
	List<Version> buildTools = <Version>[]; // 19.1.0, 22.0.1, ...

	final Directory buildToolsDir = directory.childDirectory('build-tools');
	if (buildToolsDir.existsSync()) {
	buildTools = buildToolsDir
	.listSync()
	.map((FileSystemEntity entity) {
	try {
	return Version.parse(entity.basename);
	} on Exception {
	return null;
	}
	})
	.whereType<Version>()
	.toList();
	}

	// Match up platforms with the best corresponding build-tools.
	_sdkVersions = _platforms.map<AndroidSdkVersion?>((Directory platformDir) {
	final String platformName = platformDir.basename;
	int platformVersion;

	try {
	final Match? numberedVersion = _numberedAndroidPlatformRe.firstMatch(platformName);
	if (numberedVersion != null) {
	platformVersion = int.parse(numberedVersion.group(1)!);
	} else {
	final String buildProps = platformDir.childFile('build.prop').readAsStringSync();
	final Iterable<Match> versionMatches = const LineSplitter()
	.convert(buildProps)
	.map<RegExpMatch?>(_sdkVersionRe.firstMatch)
	.whereType<Match>();

	if (versionMatches.isEmpty) {
	return null;
	}

	final String? versionString = versionMatches.first.group(1);
	if (versionString == null) {
	return null;
	}
	platformVersion = int.parse(versionString);
	}
	} on Exception {
	return null;
	}

	Version? buildToolsVersion = Version.primary(buildTools.where((Version version) {
	return version.major == platformVersion;
	}).toList());

	buildToolsVersion ??= Version.primary(buildTools);

	if (buildToolsVersion == null) {
	return null;
	}

	return AndroidSdkVersion._(
	this,
	sdkLevel: platformVersion,
	platformName: platformName,
	buildToolsVersion: buildToolsVersion,
	fileSystem: fileSystem ?? globals.fs,
	);
	}).whereType<AndroidSdkVersion>().toList();

	_sdkVersions.sort();

	_latestVersion = _sdkVersions.isEmpty ? null : _sdkVersions.last;
	}

	/// Returns the filesystem path of the Android SDK manager tool.
	String? get sdkManagerPath {
	final String executable = globals.platform.isWindows
	? 'sdkmanager.bat'
	: 'sdkmanager';
	final String? path = getCmdlineToolsPath(executable, skipOldTools: true);
	if (path != null) {
	return path;
	}
	return null;
	}

	/// Returns the version of the Android SDK manager tool or null if not found.
	String? get sdkManagerVersion {
	if (sdkManagerPath == null \|\| !globals.processManager.canRun(sdkManagerPath)) {
	throwToolExit(
	'Android sdkmanager not found. Update to the latest Android SDK and ensure that '
	'the cmdline-tools are installed to resolve this.'
	);
	}
	final RunResult result = globals.processUtils.runSync(
	<String>[sdkManagerPath!, '--version'],
	environment: _java?.environment,
	);
	if (result.exitCode != 0) {
	globals.printTrace('sdkmanager --version failed: exitCode: ${result.exitCode} stdout: ${result.stdout} stderr: ${result.stderr}');
	return null;
	}
	return result.stdout.trim();
	}

	@override
	String toString() => 'AndroidSdk: $directory';
	}

	class AndroidSdkVersion implements Comparable<AndroidSdkVersion> {
	AndroidSdkVersion._(
	this.sdk, {
	required this.sdkLevel,
	required this.platformName,
	required this.buildToolsVersion,
	required FileSystem fileSystem,
	}) : _fileSystem = fileSystem;

	final AndroidSdk sdk;
	final int sdkLevel;
	final String platformName;
	final Version buildToolsVersion;

	final FileSystem _fileSystem;

	String get buildToolsVersionName => buildToolsVersion.toString();

	String get androidJarPath => getPlatformsPath('android.jar');

	/// Return the path to the android application package tool.
	///
	/// This is used to dump the xml in order to launch built android applications.
	///
	/// See also:
	/// * [AndroidApk.fromApk], which depends on this to determine application identifiers.
	String get aaptPath => getBuildToolsPath('aapt');

	List<String> validateSdkWellFormed() {
	final String? existsAndroidJarPath = _exists(androidJarPath);
	if (existsAndroidJarPath != null) {
	return <String>[existsAndroidJarPath];
	}

	final String? canRunAaptPath = _canRun(aaptPath);
	if (canRunAaptPath != null) {
	return <String>[canRunAaptPath];
	}

	return <String>[];
	}

	String getPlatformsPath(String itemName) {
	return sdk.directory.childDirectory('platforms').childDirectory(platformName).childFile(itemName).path;
	}

	String getBuildToolsPath(String binaryName) {
	return sdk.directory.childDirectory('build-tools').childDirectory(buildToolsVersionName).childFile(binaryName).path;
	}

	@override
	int compareTo(AndroidSdkVersion other) => sdkLevel - other.sdkLevel;

	@override
	String toString() => '[${sdk.directory}, SDK version $sdkLevel, build-tools $buildToolsVersionName]';

	String? _exists(String path) {
	if (!_fileSystem.isFileSync(path)) {
	return 'Android SDK file not found: $path.';
	}
	return null;
	}

	String? _canRun(String path) {
	if (!globals.processManager.canRun(path)) {
	return 'Android SDK file not found: $path.';
	}
	return null;
	}
	}