BlockingQueue的四组API

BlockingQueue的四组API

• 会抛出异常

  public class Test01 {
      public static void main(String[] args) {
          test();
      }
      public static void test() {
          //队列的大小：3
          ArrayBlockingQueue<Object> blockingQueue = new ArrayBlockingQueue<>(3);
          System.out.println(blockingQueue.add("a"));
          System.out.println(blockingQueue.add("b"));
          System.out.println(blockingQueue.add("c"));
          /*java.lang.IllegalStateException : 大小满了
          System.out.println(blockingQueue.add("d"));*/
  		 System.out.println("队首是"+blockingQueue.element());//检测队首元素 会抛出异常
          System.out.println(blockingQueue.remove());
          System.out.println(blockingQueue.remove());
          System.out.println(blockingQueue.remove());
  
          /*队列大小只有3
          java.util.NoSuchElementException  抛出异常
          System.out.println(blockingQueue.remove());*/
      }
  }
  

• 有返回值 不会抛出异常

  public class Test01 {
      public static void main(String[] args) {
          test();
      }
      public static void test() {
          //队列的大小：3
          ArrayBlockingQueue<Object> blockingQueue = new ArrayBlockingQueue<>(3);
          System.out.println(blockingQueue.offer("a"));
          System.out.println(blockingQueue.offer("b"));
          System.out.println(blockingQueue.offer("c"));
          // System.out.println(blockingQueue.offer("d"));   //false 不抛出异常
          System.out.println("队首是"+blockingQueue.peek());//检测队首元素 不会抛出异常
          System.out.println(blockingQueue.poll());
          System.out.println(blockingQueue.poll());
          System.out.println(blockingQueue.poll());
          // System.out.println(blockingQueue.poll());   //null 多删除也不抛出异常:
      }
  }
  

• 等待 阻塞

  public static void main(String[] args) throws InterruptedException {
      test();
  }
  public static void test() throws InterruptedException {
      //队列的大小：3
      ArrayBlockingQueue<Object> blockingQueue = new ArrayBlockingQueue<>(3);
      blockingQueue.put("a");
      blockingQueue.put("b");
      blockingQueue.put("c");
      /*队列没有位置 d 会一值等待
      blockingQueue.put("d");   */
  
      System.out.println(blockingQueue.take());
      System.out.println(blockingQueue.take());
      System.out.println(blockingQueue.take());
     /* 没有元素 会一直等待
      System.out.println(blockingQueue.take());*/
  }
  

• 超时等待 自动退出

  public class Test01 {
      public static void main(String[] args) throws InterruptedException {
          test();
      }
      public static void test() throws InterruptedException {
          //队列的大小：3
          ArrayBlockingQueue<Object> blockingQueue = new ArrayBlockingQueue<>(3);
         blockingQueue.offer("a");
         blockingQueue.offer("b");
         blockingQueue.offer("c");
         // blockingQueue.offer("d",2, TimeUnit.SECONDS);  //等待超过两秒后 就退出
  
          System.out.println(blockingQueue.poll());
          System.out.println(blockingQueue.poll());
          System.out.println(blockingQueue.poll());
          blockingQueue.poll(2,TimeUnit.SECONDS);  //等待超过两秒后 就退出
      }
  }
  

方式	抛出异常	有返回值,不抛出异常	阻塞等待	超时等待
添加	add	offer	put	offer(,,)
移除	remove	poll	take	poll(,)
查看队列首位元素	element	peek	…	…