这个代码线程在BlockingQueue上是否安全

Question

在javadoc中，我看到addAll对BlockingQueue不是线程安全的，所以我认为以下代码不是线程安全的，但我运行了很长时间，而不是异常抛出有人可以解释一下吗？感谢

public class Test {

  public static void main(String[] args) throws InterruptedException {
    LinkedBlockingQueue<String> queue = new LinkedBlockingQueue<String>();
    new Producer(queue).start();
    new Consumer(queue).start();
  }

  public static class Producer extends Thread {
    private LinkedBlockingQueue<String> queue;

    public Producer(LinkedBlockingQueue<String> queue) {
      this.queue = queue;
    }

    @Override
    public void run() {
      while (true) {
        List<String> list = new ArrayList<String>();
        for (int i = 0; i < 5; ++i) {
          list.add(i + "");
        }
        this.queue.addAll(list);
      }
    }
  }

  public static class Consumer extends Thread {
    private LinkedBlockingQueue<String> queue;
    public Consumer(LinkedBlockingQueue<String> queue) {
      this.queue = queue;
    }

    @Override
    public void run() {
      while (true) {
        List<String> result = Lists.newArrayList();
        queue.drainTo(result);
        System.out.println("Take " + result.size());
      }
    }
  }
}