HandlerThreadWrapper { public @NonNull Handler getHandler() { return this.mHandler; } HandlerThreadWrapper(@NonNull String threadName);  HandlerThreadWrapper(@NonNull String threadName, @Nullable Handler.Callback callback); @NonNull Handler getHandler(); boolean isAlive(); void quit();  }
@Test public void getHandler() throws Exception { HandlerThreadWrapper mHandlerThreadWrapper = new HandlerThreadWrapper("test"); Handler handler = mHandlerThreadWrapper.getHandler(); assertNotNull(handler); }