如何在 Android 7.0 上获取主线程的堆栈跟踪？

Question

作为对Android 7.0 的简单测试，Thread.getAllStackTraces() API 无法获取主线程（属于"main" 线程组）的堆栈跟踪。但是主线程的堆栈跟踪可以通过 Thread.currentThread().getStackTrace() 得到，如下所示。

测试代码：

    Set<Thread> threads = Thread.getAllStackTraces().keySet();
    Log.d("Test", String.format("Number of threads get by 'Thread.getAllStackTraces()': %d", threads.size()));
    for (Thread thread : threads) {
        if (thread != null) {
            Log.d("Test", String.format("[ID]: %d, [Name]: %s", thread.getId(), thread.getName()));
        }
    }
    Log.d("Test", String.format("Current thread name: %s", Thread.currentThread().getName()));
    Log.d("Test", String.format("Current group name: %s", Thread.currentThread().getThreadGroup().getName()));
    StackTraceElement[] elements = Thread.currentThread().getStackTrace();
    for (int i = 0; i < elements.length; i++) {
        Log.d("Test", String.format("main stack element[%d]: %s", i, elements[i]));
    }

Android 4.4 的结果：

Number of threads get by 'Thread.getAllStackTraces()': 10
[ID]: 1871, [Name]: GCDaemon
[ID]: 1867, [Name]: ReferenceQueueDaemon
[ID]: 1870, [Name]: HeapTrimmerDaemon
[ID]: 1872, [Name]: Binder_1
[ID]: 1866, [Name]: JDWP
[ID]: 1868, [Name]: FinalizerDaemon
[ID]: 1869, [Name]: FinalizerWatchdogDaemon
[ID]: 1, [Name]: main
[ID]: 1873, [Name]: Binder_2
[ID]: 1865, [Name]: Signal Catcher
Current thread name: main
Current group name: main
main stack element[0]: dalvik.system.VMStack.getThreadStackTrace(Native Method)
main stack element[1]: java.lang.Thread.getStackTrace(Thread.java:580)
main stack element[2]: com.test.demo.MainActivity.onCreate(MainActivity.java:169)
main stack element[3]: android.app.Activity.performCreate(Activity.java:6117)
main stack element[4]: android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123)
main stack element[5]: android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2612)
main stack element[6]: android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2728)
main stack element[7]: android.app.ActivityThread.access0(ActivityThread.java:179)
main stack element[8]: android.app.ActivityThread$H.handleMessage(ActivityThread.java:1579)
main stack element[9]: android.os.Handler.dispatchMessage(Handler.java:111)
main stack element[10]: android.os.Looper.loop(Looper.java:194)
main stack element[11]: android.app.ActivityThread.main(ActivityThread.java:5838)
main stack element[12]: java.lang.reflect.Method.invoke(Native Method)
main stack element[13]: java.lang.reflect.Method.invoke(Method.java:372)
main stack element[14]: com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1009)
main stack element[15]: com.android.internal.os.ZygoteInit.main(ZygoteInit.java:804)

Android7.0 的结果：

Number of threads get by 'Thread.getAllStackTraces()': 4
[ID]: 116, [Name]: FinalizerWatchdogDaemon
[ID]: 114, [Name]: ReferenceQueueDaemon
[ID]: 115, [Name]: FinalizerDaemon
[ID]: 117, [Name]: HeapTaskDaemon
Current thread name: main
Current group name: main
main stack element[0]: dalvik.system.VMStack.getThreadStackTrace(Native Method)
main stack element[1]: java.lang.Thread.getStackTrace(Thread.java:1566)
main stack element[2]: com.test.demo.MainActivity.onCreate(MainActivity.java:169)
main stack element[3]: android.app.Activity.performCreate(Activity.java:6664)
main stack element[4]: android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
main stack element[5]: android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2599)
main stack element[6]: android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
main stack element[7]: android.app.ActivityThread.-wrap12(ActivityThread.java)
main stack element[8]: android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
main stack element[9]: android.os.Handler.dispatchMessage(Handler.java:102)
main stack element[10]: android.os.Looper.loop(Looper.java:154)
main stack element[11]: android.app.ActivityThread.main(ActivityThread.java:6077)
main stack element[12]: java.lang.reflect.Method.invoke(Native Method)
main stack element[13]: com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)
main stack element[14]: com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)

好像是经过Android的权限获取线程信息的相关内容。但是 Android Device Monitor 可以获取所有线程及其详细信息。

那么在>=Android7.0上有没有办法获取主线程的堆栈？

感谢阅读和回答。

Answer 1

我可以确认显然 getAllStackTraces() 没有为主线程 UI 提供堆栈跟踪，无论出于何种原因。但是，有一种方法：在任何后台线程中，您都可以调用 Looper.getMainLooper().getThread().getStackTrace()（或者只需记住 UI 代码中某处的 Thread 对象并对其调用 getStackTrace()）。

您是否正在做一些性能分析？我试过 Android 监视器，它比没用还糟糕——不仅 UI 非常慢，而且它捕获了完全不匹配的错误堆栈跟踪！我正在考虑编写一个非常简单的 suckless 分析器，您可以随意启动和停止它，它只会将分析详细信息转储到 Android 控制台。

如何在 Android 7.0 上获取主线程的堆栈跟踪？

How to get stack trace of main thread on Android 7.0?

android

stack-trace