poll()
Java中的ArrayBlockingQueue类的方法检索并删除此队列的头部,如果此队列为空,则返回null。
语法如下:
E poll()
要使用ArrayBlockingQueue类,您需要导入以下包:
import java.util.concurrent.ArrayBlockingQueue;
以下是实现poll()
Java ArrayBlockingQueue类的方法的示例:
import java.util.concurrent.ArrayBlockingQueue; public class Demo { public static void main(String[] args) throws InterruptedException { ArrayBlockingQueue<Integer> q = new ArrayBlockingQueue<Integer>(10); q.add(200); q.add(310); q.add(400); q.add(450); q.add(500); q.add(550); q.add(700); System.out.println("ArrayBlockingQueue = " + q); System.out.println("Head of the queue = "+q.poll()); System.out.println("Head of the queue now = "+q.poll()); System.out.println("ArrayBlockingQueue = " + q); } }
输出结果
ArrayBlockingQueue = [200, 310, 400, 450, 500, 550, 700] Head of the queue = 200 Head of the queue now = 310 ArrayBlockingQueue = [400, 450, 500, 550, 700]