Caused by: java.io.IOException: error=2, No such file or directory
本着尝鲜的心态，最近把Android studio升级到了Android Studio 3.1.2，升级之后项目突然不能正常编译运行了，报:
:app:transformNativeLibsWithStripDebugSymbolForDebug
Caused by: java.io.IOException: error=2, No such file or directory
详细报错信息：
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:transformNativeLibsWithStripDebugSymbolForDebug'. at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:100) at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:70) at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:63) at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:54) at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58) at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:88) at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:52) at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52) at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54) at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43) at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34) at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.run(DefaultTaskGraphExecuter.java:248) at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336) at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328) at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:197) at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:107) at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:241) at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:230) at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.processTask(DefaultTaskPlanExecutor.java:124) at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.access$200(DefaultTaskPlanExecutor.java:80) at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:105) at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:99) at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.execute(DefaultTaskExecutionPlan.java:625) at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.executeWithTask(DefaultTaskExecutionPlan.java:580) at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.run(DefaultTaskPlanExecutor.java:99) at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63) at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55) at java.lang.Thread.run(Thread.java:745) Caused by: org.gradle.process.internal.ExecException: A problem occurred starting process 'command '/Users/yang/Library/Android/sdk/ndk-bundle/toolchains/mips64el-linux-android-4.9/prebuilt/darwin-x86_64/bin/mips64el-linux-android-strip'' at org.gradle.process.internal.DefaultExecHandle.execExceptionFor(DefaultExecHandle.java:220) at org.gradle.process.internal.DefaultExecHandle.setEndStateInfo(DefaultExecHandle.java:204) at org.gradle.process.internal.DefaultExecHandle.failed(DefaultExecHandle.java:340) at org.gradle.process.internal.ExecHandleRunner.run(ExecHandleRunner.java:86) at org.gradle.internal.operations.BuildOperationIdentifierPreservingRunnable.run(BuildOperationIdentifierPreservingRunnable.java:39) ... 6 more Caused by: net.rubygrapefruit.platform.NativeException: Could not start '/Users/yang/Library/Android/sdk/ndk-bundle/toolchains/mips64el-linux-android-4.9/prebuilt/darwin-x86_64/bin/mips64el-linux-android-strip' at net.rubygrapefruit.platform.internal.DefaultProcessLauncher.start(DefaultProcessLauncher.java:27) at net.rubygrapefruit.platform.internal.WrapperProcessLauncher.start(WrapperProcessLauncher.java:36) at org.gradle.process.internal.ExecHandleRunner.run(ExecHandleRunner.java:68) ... 7 more Caused by: java.io.IOException: Cannot run program "/Users/yang/Library/Android/sdk/ndk-bundle/toolchains/mips64el-linux-android-4.9/prebuilt/darwin-x86_64/bin/mips64el-linux-android-strip" (in directory "/Users/yang/AndroidStudioProjects/VPOS/app"): error=2, No such file or directory at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048) at net.rubygrapefruit.platform.internal.DefaultProcessLauncher.start(DefaultProcessLauncher.java:25) ... 9 more Caused by: java.io.IOException: error=2, No such file or directory at java.lang.UNIXProcess.forkAndExec(Native Method) at java.lang.UNIXProcess.<init>(UNIXProcess.java:247) at java.lang.ProcessImpl.start(ProcessImpl.java:134) at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029) ... 10 more看最后一段报错信息：
Caused by: java.io.IOException: error=2, No such file or directory at java.lang.UNIXProcess.forkAndExec(Native Method) at java.lang.UNIXProcess.<init>(UNIXProcess.java:247) at java.lang.ProcessImpl.start(ProcessImpl.java:134) at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029) ... 10 morejava IO异常，找不到文件或者目录。一般报这种问题，都是缺少文件。既然是缺少文件，那我们向上看，看看缺少哪些文件或者目录，找到了这个路径：
/Users/yang/Library/Android/sdk/ndk-bundle/toolchains/mips64el-linux-android-4.9/prebuilt/darwin-x86_64/bin/mips64el-linux-android-strip我们根据这个路径，去看看是不是真的缺少这个文件或者目录：
/Users/yang/Library/Android/sdk/ndk-bundle/toolchains/mips64el-linux-android-4.9/prebuilt/darwin-x86_64/
上面这个目录下缺少文件，只到了.../prebuilt/darwin-x86_64/这个层级，缺少.../prebuilt/darwin-x86_64/bin/mips64el-linux-android-strip
这个目录是ndk预编译的一种工具链，用来预编译以mips CPU指令集的so文件。
我们看到Android SDK中ndk的版本为17.0.4754217，最新的。我们猜测Google是在新版本的NDK中删去了对mips指令集CPU预编译的支持。
我们找一下老版本的NDK文件，看看该目录下是不是有完整的mips工具链文件，从这里下载老版本NDK文件：
https://developer.android.com/ndk/downloads/older_releases
我们下载上一个版本16b，下载解压后，到相同路径下去看，文件都是齐全的：
至此我们找到了问题的原因，Google在新版本17.0.4754217的NDK中，删去了对mips指令集CPU预编译的支持，在预编译具有mips的so文件的项目时，就会报缺少文件或者目录的错误。
这种方法最简单，在gradle文件中配置打包参数，打包时排除/mips64/和/mips/文件下的所有so文件。
android { ... packagingOptions { exclude 'lib/mips64/*.so' exclude 'lib/mips/*.so' } }删除/mips64/和/mips/文件下的所有so文件
将SDK中的NDK回退到16b版本，去这里下载16b版本的ndk文件
https://developer.android.com/ndk/downloads/older_releases
解压之后，替换掉原来SDK中的ndk-bundle文件，即.../Android/sdk/ndk-bundle/
或者将解压后的.../prebuilt/darwin-x86_64/，复制过去，这样17版本的ndk也具有了预编译mips so文件的能力