你可以使用一个本地的 final 变量,变量需要是 non-primitive 类型,所以你可以使用一个数组。也需要同步两个线程,例如使用一个 CountDownLatch:
public void test()
{
final CountDownLatch latch = new CountDownLatch(1);
final int[] value = new int[1];
Thread uiThread = new HandlerThread("UIHandler"){
@Override
public synchronized void run(){
value[0] = 2;
latch.countDown(); // Release await() in the test thread.
}
};
uiThread.start();
latch.await(); // Wait for countDown() in the UI thread.
// value[0] holds 2 at this point.
}
也可以使用 Executor 和 Callable:
public void test() throws InterruptedException, ExecutionException
{
ExecutorService executor = Executors.newSingleThreadExecutor();
Callable<Integer> callable = new Callable<Integer>() {
@Override
public Integer call() {
return 2;
}
};
Future<Integer> future = executor.submit(callable);
// future.get() returns 2
executor.shutdown();
}