Java中的 ConcurrentLinkedQueue isEmpty() 方法
ConcurrentLinkedQueue的isEmpty()方法用于检查此队列是否为空。如果 ConcurrentLinkedQueue 包含零个元素,则返回 true 意味着 ConcurrentLinkedQueue 是否为空。
句法:
public boolean isEmpty()
返回:如果此 ConcurrentLinkedQueue 包含零个元素,则此方法返回true 。
下面的程序说明了 ConcurrentLinkedQueue 的 isEmpty() 方法:
示例 1:
// Java Program Demonstrate isEmpty()
// method of ConcurrentLinkedQueue
import java.util.concurrent.*;
public class GFG {
public static void main(String[] args)
{
// create an ConcurrentLinkedQueue
ConcurrentLinkedQueue
queue = new ConcurrentLinkedQueue();
// Add String to queue
queue.add("Aman");
queue.add("Amar");
queue.add("Sanjeet");
queue.add("Rabi");
// Displaying the existing ConcurrentLinkedQueue
System.out.println("ConcurrentLinkedQueue: " + queue);
// check whether queue isEmpty or not
boolean response1 = queue.isEmpty();
// print after applying isEmpty method
System.out.println("Is Queue empty: " + response1);
}
}
输出:
ConcurrentLinkedQueue: [Aman, Amar, Sanjeet, Rabi]
Is Queue empty: false
示例 2:
// Java Program Demonstrate isEmpty()
// method of ConcurrentLinkedQueue
import java.util.concurrent.*;
public class GFG {
public static void main(String[] args)
{
// create an ConcurrentLinkedQueue
ConcurrentLinkedQueue
queue = new ConcurrentLinkedQueue();
// Displaying the existing ConcurrentLinkedQueue
System.out.println("ConcurrentLinkedQueue: " + queue);
// check whether queue is Empty
boolean response1 = queue.isEmpty();
// print after applying isEmpty method
System.out.println("Is queue empty : " + response1);
}
}
输出:
ConcurrentLinkedQueue: []
Is queue empty : true
参考: https: Java/util/concurrent/ConcurrentLinkedQueue.html#isEmpty–