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1// Copyright 2016 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5import 'package:meta/meta.dart';
6
7import '../base/common.dart';
8import '../base/context.dart';
9import '../base/file_system.dart';
10import '../base/io.dart' show ProcessResult;
11import '../base/os.dart';
12import '../base/platform.dart';
13import '../base/process.dart';
14import '../base/process_manager.dart';
15import '../base/version.dart';
16import '../convert.dart';
17import '../globals.dart';
18import 'android_studio.dart' as android_studio;
19
20AndroidSdk get androidSdk => context.get<AndroidSdk>();
21
22const String kAndroidHome = 'ANDROID_HOME';
23const String kAndroidSdkRoot = 'ANDROID_SDK_ROOT';
24
25// Android SDK layout:
26
27// $ANDROID_HOME/platform-tools/adb
28
29// $ANDROID_HOME/build-tools/19.1.0/aapt, dx, zipalign
30// $ANDROID_HOME/build-tools/22.0.1/aapt
31// $ANDROID_HOME/build-tools/23.0.2/aapt
32// $ANDROID_HOME/build-tools/24.0.0-preview/aapt
33// $ANDROID_HOME/build-tools/25.0.2/apksigner
34
35// $ANDROID_HOME/platforms/android-22/android.jar
36// $ANDROID_HOME/platforms/android-23/android.jar
37// $ANDROID_HOME/platforms/android-N/android.jar
38
39final RegExp _numberedAndroidPlatformRe = RegExp(r'^android-([0-9]+)$');
40final RegExp _sdkVersionRe = RegExp(r'^ro.build.version.sdk=([0-9]+)$');
41
42/// The minimum Android SDK version we support.
43const int minimumAndroidSdkVersion = 25;
44
45/// Locate ADB. Prefer to use one from an Android SDK, if we can locate that.
46/// This should be used over accessing androidSdk.adbPath directly because it
47/// will work for those users who have Android Platform Tools installed but
48/// not the full SDK.
49String getAdbPath([ AndroidSdk existingSdk ]) {
50  if (existingSdk?.adbPath != null)
51    return existingSdk.adbPath;
52
53  final AndroidSdk sdk = AndroidSdk.locateAndroidSdk();
54
55  if (sdk?.latestVersion == null) {
56    return os.which('adb')?.path;
57  } else {
58    return sdk.adbPath;
59  }
60}
61
62/// Locate 'emulator'. Prefer to use one from an Android SDK, if we can locate that.
63/// This should be used over accessing androidSdk.emulatorPath directly because it
64/// will work for those users who have Android Tools installed but
65/// not the full SDK.
66String getEmulatorPath([ AndroidSdk existingSdk ]) {
67  return existingSdk?.emulatorPath ??
68    AndroidSdk.locateAndroidSdk()?.emulatorPath;
69}
70
71/// Locate the path for storing AVD emulator images. Returns null if none found.
72String getAvdPath() {
73
74  final List<String> searchPaths = <String>[
75    platform.environment['ANDROID_AVD_HOME'],
76  ];
77
78  if (platform.environment['HOME'] != null)
79    searchPaths.add(fs.path.join(platform.environment['HOME'], '.android', 'avd'));
80
81  if (platform.isWindows) {
82    final String homeDrive = platform.environment['HOMEDRIVE'];
83    final String homePath = platform.environment['HOMEPATH'];
84
85    if (homeDrive != null && homePath != null) {
86      // Can't use path.join for HOMEDRIVE/HOMEPATH
87      // https://github.com/dart-lang/path/issues/37
88      final String home = homeDrive + homePath;
89      searchPaths.add(fs.path.join(home, '.android', 'avd'));
90    }
91  }
92
93  return searchPaths.where((String p) => p != null).firstWhere(
94    (String p) => fs.directory(p).existsSync(),
95    orElse: () => null,
96  );
97}
98
99/// Locate 'avdmanager'. Prefer to use one from an Android SDK, if we can locate that.
100/// This should be used over accessing androidSdk.avdManagerPath directly because it
101/// will work for those users who have Android Tools installed but
102/// not the full SDK.
103String getAvdManagerPath([ AndroidSdk existingSdk ]) {
104  return existingSdk?.avdManagerPath ??
105    AndroidSdk.locateAndroidSdk()?.avdManagerPath;
106}
107
108class AndroidNdkSearchError {
109  AndroidNdkSearchError(this.reason);
110
111  /// The message explaining why NDK was not found.
112  final String reason;
113}
114
115class AndroidNdk {
116  AndroidNdk._(this.directory, this.compiler, this.compilerArgs);
117
118  /// The path to the NDK.
119  final String directory;
120
121  /// The path to the NDK compiler.
122  final String compiler;
123
124  /// The mandatory arguments to the NDK compiler.
125  final List<String> compilerArgs;
126
127  /// Locate NDK within the given SDK or throw [AndroidNdkSearchError].
128  static AndroidNdk locateNdk(String androidHomeDir) {
129    if (androidHomeDir == null) {
130      throw AndroidNdkSearchError('Can not locate NDK because no SDK is found');
131    }
132
133    String findBundle(String androidHomeDir) {
134      final String ndkDirectory = fs.path.join(androidHomeDir, 'ndk-bundle');
135      if (!fs.isDirectorySync(ndkDirectory)) {
136        throw AndroidNdkSearchError('Can not locate ndk-bundle, tried: $ndkDirectory');
137      }
138      return ndkDirectory;
139    }
140
141    // Returns list that contains toolchain bin folder and compiler binary name.
142    List<String> findToolchainAndCompiler(String ndkDirectory) {
143      String directory;
144      if (platform.isLinux) {
145        directory = 'linux-x86_64';
146      } else if (platform.isMacOS) {
147        directory = 'darwin-x86_64';
148      } else {
149        throw AndroidNdkSearchError('Only Linux and macOS are supported');
150      }
151
152      final String toolchainBin = fs.path.join(ndkDirectory,
153          'toolchains', 'arm-linux-androideabi-4.9', 'prebuilt', directory,
154          'bin');
155      final String ndkCompiler = fs.path.join(toolchainBin,
156          'arm-linux-androideabi-gcc');
157      if (!fs.isFileSync(ndkCompiler)) {
158        throw AndroidNdkSearchError('Can not locate GCC binary, tried $ndkCompiler');
159      }
160
161      return <String>[toolchainBin, ndkCompiler];
162    }
163
164    List<String> findSysroot(String ndkDirectory) {
165      // If entity represents directory with name android-<version> that
166      // contains arch-arm subdirectory then returns version, otherwise
167      // returns null.
168      int toPlatformVersion(FileSystemEntity entry) {
169        if (entry is! Directory) {
170          return null;
171        }
172
173        if (!fs.isDirectorySync(fs.path.join(entry.path, 'arch-arm'))) {
174          return null;
175        }
176
177        final String name = fs.path.basename(entry.path);
178
179        const String platformPrefix = 'android-';
180        if (!name.startsWith(platformPrefix)) {
181          return null;
182        }
183
184        return int.tryParse(name.substring(platformPrefix.length));
185      }
186
187      final String platformsDir = fs.path.join(ndkDirectory, 'platforms');
188      final List<int> versions = fs
189          .directory(platformsDir)
190          .listSync()
191          .map(toPlatformVersion)
192          .where((int version) => version != null)
193          .toList(growable: false);
194      versions.sort();
195
196      final int suitableVersion = versions
197          .firstWhere((int version) => version >= 9, orElse: () => null);
198      if (suitableVersion == null) {
199        throw AndroidNdkSearchError('Can not locate a suitable platform ARM sysroot (need android-9 or newer), tried to look in $platformsDir');
200      }
201
202      final String armPlatform = fs.path.join(ndkDirectory, 'platforms',
203          'android-$suitableVersion', 'arch-arm');
204      return <String>['--sysroot', armPlatform];
205    }
206
207    int findNdkMajorVersion(String ndkDirectory) {
208      final String propertiesFile = fs.path.join(ndkDirectory, 'source.properties');
209      if (!fs.isFileSync(propertiesFile)) {
210        throw AndroidNdkSearchError('Can not establish ndk-bundle version: $propertiesFile not found');
211      }
212
213      // Parse source.properties: each line has Key = Value format.
214      final Iterable<String> propertiesFileLines = fs.file(propertiesFile)
215          .readAsStringSync()
216          .split('\n')
217          .map<String>((String line) => line.trim())
218          .where((String line) => line.isNotEmpty);
219      final Map<String, String> properties = <String, String>{};
220      for (String line in propertiesFileLines) {
221        final List<String> parts = line.split(' = ');
222        if (parts.length == 2) {
223          properties[parts[0]] = parts[1];
224        } else {
225          printError('Malformed line in ndk source.properties: "$line".');
226        }
227      }
228
229      if (!properties.containsKey('Pkg.Revision')) {
230        throw AndroidNdkSearchError('Can not establish ndk-bundle version: $propertiesFile does not contain Pkg.Revision');
231      }
232
233      // Extract major version from Pkg.Revision property which looks like <ndk-version>.x.y.
234      return int.parse(properties['Pkg.Revision'].split('.').first);
235    }
236
237    final String ndkDir = findBundle(androidHomeDir);
238    final int ndkVersion = findNdkMajorVersion(ndkDir);
239    final List<String> ndkToolchainAndCompiler = findToolchainAndCompiler(ndkDir);
240    final String ndkToolchain = ndkToolchainAndCompiler[0];
241    final String ndkCompiler = ndkToolchainAndCompiler[1];
242    final List<String> ndkCompilerArgs = findSysroot(ndkDir);
243    if (ndkVersion >= 18) {
244      // Newer versions of NDK use clang instead of gcc, which falls back to
245      // system linker instead of using toolchain linker. Force clang to
246      // use appropriate linker by passing -fuse-ld=<path-to-ld> command line
247      // flag.
248      final String ndkLinker = fs.path.join(ndkToolchain, 'arm-linux-androideabi-ld');
249      if (!fs.isFileSync(ndkLinker)) {
250        throw AndroidNdkSearchError('Can not locate linker binary, tried $ndkLinker');
251      }
252      ndkCompilerArgs.add('-fuse-ld=$ndkLinker');
253    }
254    return AndroidNdk._(ndkDir, ndkCompiler, ndkCompilerArgs);
255  }
256
257  /// Returns a descriptive message explaining why NDK can not be found within
258  /// the given SDK.
259  static String explainMissingNdk(String androidHomeDir) {
260    try {
261      locateNdk(androidHomeDir);
262      return 'Unexpected error: found NDK on the second try';
263    } on AndroidNdkSearchError catch (e) {
264      return e.reason;
265    }
266  }
267}
268
269class AndroidSdk {
270  AndroidSdk(this.directory, [this.ndk]) {
271    reinitialize();
272  }
273
274  static const String _javaHomeEnvironmentVariable = 'JAVA_HOME';
275  static const String _javaExecutable = 'java';
276
277  /// The path to the Android SDK.
278  final String directory;
279
280  /// Android NDK (can be `null`).
281  final AndroidNdk ndk;
282
283  List<AndroidSdkVersion> _sdkVersions;
284  AndroidSdkVersion _latestVersion;
285
286  /// Whether the `platform-tools` directory exists in the Android SDK.
287  ///
288  /// It is possible to have an Android SDK folder that is missing this with
289  /// the expectation that it will be downloaded later, e.g. by gradle or the
290  /// sdkmanager. The [licensesAvailable] property should be used to determine
291  /// whether the licenses are at least possibly accepted.
292  bool get platformToolsAvailable => fs.directory(fs.path.join(directory, 'platform-tools')).existsSync();
293
294  /// Whether the `licenses` directory exists in the Android SDK.
295  ///
296  /// The existence of this folder normally indicates that the SDK licenses have
297  /// been accepted, e.g. via the sdkmanager, Android Studio, or by copying them
298  /// from another workstation such as in CI scenarios. If these files are valid
299  /// gradle or the sdkmanager will be able to download and use other parts of
300  /// the SDK on demand.
301  bool get licensesAvailable => fs.directory(fs.path.join(directory, 'licenses')).existsSync();
302
303  static AndroidSdk locateAndroidSdk() {
304    String findAndroidHomeDir() {
305      String androidHomeDir;
306      if (config.containsKey('android-sdk')) {
307        androidHomeDir = config.getValue('android-sdk');
308      } else if (platform.environment.containsKey(kAndroidHome)) {
309        androidHomeDir = platform.environment[kAndroidHome];
310      } else if (platform.environment.containsKey(kAndroidSdkRoot)) {
311        androidHomeDir = platform.environment[kAndroidSdkRoot];
312      } else if (platform.isLinux) {
313        if (homeDirPath != null)
314          androidHomeDir = fs.path.join(homeDirPath, 'Android', 'Sdk');
315      } else if (platform.isMacOS) {
316        if (homeDirPath != null)
317          androidHomeDir = fs.path.join(homeDirPath, 'Library', 'Android', 'sdk');
318      } else if (platform.isWindows) {
319        if (homeDirPath != null)
320          androidHomeDir = fs.path.join(homeDirPath, 'AppData', 'Local', 'Android', 'sdk');
321      }
322
323      if (androidHomeDir != null) {
324        if (validSdkDirectory(androidHomeDir))
325          return androidHomeDir;
326        if (validSdkDirectory(fs.path.join(androidHomeDir, 'sdk')))
327          return fs.path.join(androidHomeDir, 'sdk');
328      }
329
330      // in build-tools/$version/aapt
331      final List<File> aaptBins = os.whichAll('aapt');
332      for (File aaptBin in aaptBins) {
333        // Make sure we're using the aapt from the SDK.
334        aaptBin = fs.file(aaptBin.resolveSymbolicLinksSync());
335        final String dir = aaptBin.parent.parent.parent.path;
336        if (validSdkDirectory(dir))
337          return dir;
338      }
339
340      // in platform-tools/adb
341      final List<File> adbBins = os.whichAll('adb');
342      for (File adbBin in adbBins) {
343        // Make sure we're using the adb from the SDK.
344        adbBin = fs.file(adbBin.resolveSymbolicLinksSync());
345        final String dir = adbBin.parent.parent.path;
346        if (validSdkDirectory(dir))
347          return dir;
348      }
349
350      return null;
351    }
352
353    final String androidHomeDir = findAndroidHomeDir();
354    if (androidHomeDir == null) {
355      // No dice.
356      printTrace('Unable to locate an Android SDK.');
357      return null;
358    }
359
360    // Try to find the NDK compiler. If we can't find it, it's also ok.
361    AndroidNdk ndk;
362    try {
363      ndk = AndroidNdk.locateNdk(androidHomeDir);
364    } on AndroidNdkSearchError {
365      // Ignore AndroidNdkSearchError's but don't ignore any other
366      // exceptions.
367    }
368
369    return AndroidSdk(androidHomeDir, ndk);
370  }
371
372  static bool validSdkDirectory(String dir) {
373    return sdkDirectoryHasLicenses(dir) || sdkDirectoryHasPlatformTools(dir);
374  }
375
376  static bool sdkDirectoryHasPlatformTools(String dir) {
377    return fs.isDirectorySync(fs.path.join(dir, 'platform-tools'));
378  }
379
380  static bool sdkDirectoryHasLicenses(String dir) {
381    return fs.isDirectorySync(fs.path.join(dir, 'licenses'));
382  }
383
384  List<AndroidSdkVersion> get sdkVersions => _sdkVersions;
385
386  AndroidSdkVersion get latestVersion => _latestVersion;
387
388  String get adbPath => getPlatformToolsPath(platform.isWindows ? 'adb.exe' : 'adb');
389
390  String get emulatorPath => getEmulatorPath();
391
392  String get avdManagerPath => getAvdManagerPath();
393
394  Directory get _platformsDir => fs.directory(fs.path.join(directory, 'platforms'));
395
396  Iterable<Directory> get _platforms {
397    Iterable<Directory> platforms = <Directory>[];
398    if (_platformsDir.existsSync()) {
399      platforms = _platformsDir
400        .listSync()
401        .whereType<Directory>();
402    }
403    return platforms;
404  }
405
406  /// Validate the Android SDK. This returns an empty list if there are no
407  /// issues; otherwise, it returns a list of issues found.
408  List<String> validateSdkWellFormed() {
409    if (adbPath == null || !processManager.canRun(adbPath))
410      return <String>['Android SDK file not found: ${adbPath ?? 'adb'}.'];
411
412    if (sdkVersions.isEmpty || latestVersion == null) {
413      final StringBuffer msg = StringBuffer('No valid Android SDK platforms found in ${_platformsDir.path}.');
414      if (_platforms.isEmpty) {
415        msg.write(' Directory was empty.');
416      } else {
417        msg.write(' Candidates were:\n');
418        msg.write(_platforms
419          .map((Directory dir) => '  - ${dir.basename}')
420          .join('\n'));
421      }
422      return <String>[msg.toString()];
423    }
424
425    return latestVersion.validateSdkWellFormed();
426  }
427
428  String getPlatformToolsPath(String binaryName) {
429    final String path = fs.path.join(directory, 'platform-tools', binaryName);
430    if (fs.file(path).existsSync())
431      return path;
432    return null;
433  }
434
435  String getEmulatorPath() {
436    final String binaryName = platform.isWindows ? 'emulator.exe' : 'emulator';
437    // Emulator now lives inside "emulator" but used to live inside "tools" so
438    // try both.
439    final List<String> searchFolders = <String>['emulator', 'tools'];
440    for (final String folder in searchFolders) {
441      final String path = fs.path.join(directory, folder, binaryName);
442      if (fs.file(path).existsSync())
443        return path;
444    }
445    return null;
446  }
447
448  String getAvdManagerPath() {
449    final String binaryName = platform.isWindows ? 'avdmanager.bat' : 'avdmanager';
450    final String path = fs.path.join(directory, 'tools', 'bin', binaryName);
451    if (fs.file(path).existsSync())
452      return path;
453    return null;
454  }
455
456  /// Sets up various paths used internally.
457  ///
458  /// This method should be called in a case where the tooling may have updated
459  /// SDK artifacts, such as after running a gradle build.
460  void reinitialize() {
461    List<Version> buildTools = <Version>[]; // 19.1.0, 22.0.1, ...
462
463    final Directory buildToolsDir = fs.directory(fs.path.join(directory, 'build-tools'));
464    if (buildToolsDir.existsSync()) {
465      buildTools = buildToolsDir
466        .listSync()
467        .map((FileSystemEntity entity) {
468          try {
469            return Version.parse(entity.basename);
470          } catch (error) {
471            return null;
472          }
473        })
474        .where((Version version) => version != null)
475        .toList();
476    }
477
478    // Match up platforms with the best corresponding build-tools.
479    _sdkVersions = _platforms.map<AndroidSdkVersion>((Directory platformDir) {
480      final String platformName = platformDir.basename;
481      int platformVersion;
482
483      try {
484        final Match numberedVersion = _numberedAndroidPlatformRe.firstMatch(platformName);
485        if (numberedVersion != null) {
486          platformVersion = int.parse(numberedVersion.group(1));
487        } else {
488          final String buildProps = platformDir.childFile('build.prop').readAsStringSync();
489          final String versionString = const LineSplitter()
490              .convert(buildProps)
491              .map<Match>(_sdkVersionRe.firstMatch)
492              .firstWhere((Match match) => match != null)
493              .group(1);
494          platformVersion = int.parse(versionString);
495        }
496      } catch (error) {
497        return null;
498      }
499
500      Version buildToolsVersion = Version.primary(buildTools.where((Version version) {
501        return version.major == platformVersion;
502      }).toList());
503
504      buildToolsVersion ??= Version.primary(buildTools);
505
506      if (buildToolsVersion == null)
507        return null;
508
509      return AndroidSdkVersion._(
510        this,
511        sdkLevel: platformVersion,
512        platformName: platformName,
513        buildToolsVersion: buildToolsVersion,
514      );
515    }).where((AndroidSdkVersion version) => version != null).toList();
516
517    _sdkVersions.sort();
518
519    _latestVersion = _sdkVersions.isEmpty ? null : _sdkVersions.last;
520  }
521
522  /// Returns the filesystem path of the Android SDK manager tool or null if not found.
523  String get sdkManagerPath {
524    return fs.path.join(directory, 'tools', 'bin', 'sdkmanager');
525  }
526
527  /// First try Java bundled with Android Studio, then sniff JAVA_HOME, then fallback to PATH.
528  static String findJavaBinary() {
529
530    if (android_studio.javaPath != null)
531      return fs.path.join(android_studio.javaPath, 'bin', 'java');
532
533    final String javaHomeEnv = platform.environment[_javaHomeEnvironmentVariable];
534    if (javaHomeEnv != null) {
535      // Trust JAVA_HOME.
536      return fs.path.join(javaHomeEnv, 'bin', 'java');
537    }
538
539    // MacOS specific logic to avoid popping up a dialog window.
540    // See: http://stackoverflow.com/questions/14292698/how-do-i-check-if-the-java-jdk-is-installed-on-mac.
541    if (platform.isMacOS) {
542      try {
543        final String javaHomeOutput = runCheckedSync(<String>['/usr/libexec/java_home'], hideStdout: true);
544        if (javaHomeOutput != null) {
545          final List<String> javaHomeOutputSplit = javaHomeOutput.split('\n');
546          if ((javaHomeOutputSplit != null) && (javaHomeOutputSplit.isNotEmpty)) {
547            final String javaHome = javaHomeOutputSplit[0].trim();
548            return fs.path.join(javaHome, 'bin', 'java');
549          }
550        }
551      } catch (_) { /* ignore */ }
552    }
553
554    // Fallback to PATH based lookup.
555    return os.which(_javaExecutable)?.path;
556  }
557
558  Map<String, String> _sdkManagerEnv;
559  /// Returns an environment with the Java folder added to PATH for use in calling
560  /// Java-based Android SDK commands such as sdkmanager and avdmanager.
561  Map<String, String> get sdkManagerEnv {
562    if (_sdkManagerEnv == null) {
563      // If we can locate Java, then add it to the path used to run the Android SDK manager.
564      _sdkManagerEnv = <String, String>{};
565      final String javaBinary = findJavaBinary();
566      if (javaBinary != null) {
567        _sdkManagerEnv['PATH'] =
568            fs.path.dirname(javaBinary) + os.pathVarSeparator + platform.environment['PATH'];
569      }
570    }
571    return _sdkManagerEnv;
572  }
573
574  /// Returns the version of the Android SDK manager tool or null if not found.
575  String get sdkManagerVersion {
576    if (!processManager.canRun(sdkManagerPath))
577      throwToolExit('Android sdkmanager not found. Update to the latest Android SDK to resolve this.');
578    final ProcessResult result = processManager.runSync(<String>[sdkManagerPath, '--version'], environment: sdkManagerEnv);
579    if (result.exitCode != 0) {
580      printTrace('sdkmanager --version failed: exitCode: ${result.exitCode} stdout: ${result.stdout} stderr: ${result.stderr}');
581      return null;
582    }
583    return result.stdout.trim();
584  }
585
586  @override
587  String toString() => 'AndroidSdk: $directory';
588}
589
590class AndroidSdkVersion implements Comparable<AndroidSdkVersion> {
591  AndroidSdkVersion._(
592    this.sdk, {
593    @required this.sdkLevel,
594    @required this.platformName,
595    @required this.buildToolsVersion,
596  }) : assert(sdkLevel != null),
597       assert(platformName != null),
598       assert(buildToolsVersion != null);
599
600  final AndroidSdk sdk;
601  final int sdkLevel;
602  final String platformName;
603  final Version buildToolsVersion;
604
605  String get buildToolsVersionName => buildToolsVersion.toString();
606
607  String get androidJarPath => getPlatformsPath('android.jar');
608
609  String get aaptPath => getBuildToolsPath('aapt');
610
611  List<String> validateSdkWellFormed() {
612    if (_exists(androidJarPath) != null)
613      return <String>[_exists(androidJarPath)];
614
615    if (_canRun(aaptPath) != null)
616      return <String>[_canRun(aaptPath)];
617
618    return <String>[];
619  }
620
621  String getPlatformsPath(String itemName) {
622    return fs.path.join(sdk.directory, 'platforms', platformName, itemName);
623  }
624
625  String getBuildToolsPath(String binaryName) {
626    return fs.path.join(sdk.directory, 'build-tools', buildToolsVersionName, binaryName);
627  }
628
629  @override
630  int compareTo(AndroidSdkVersion other) => sdkLevel - other.sdkLevel;
631
632  @override
633  String toString() => '[${sdk.directory}, SDK version $sdkLevel, build-tools $buildToolsVersionName]';
634
635  String _exists(String path) {
636    if (!fs.isFileSync(path))
637      return 'Android SDK file not found: $path.';
638    return null;
639  }
640
641  String _canRun(String path) {
642    if (!processManager.canRun(path))
643      return 'Android SDK file not found: $path.';
644    return null;
645  }
646}
647