Java 中的 blocking reque removefirst occurrence()方法,带示例

原文:https://www . geeksforgeeks . org/blockingreque-removefirst occurrence-method-in-Java-with-examples/

移除第一次出现()方法阻塞请求从该数据中移除指定元素的第一次出现。如果 deque 不包含该元素,它将保持不变。如果这个 deque 包含指定的元素,则返回 true,否则返回 false。

语法:

public boolean removeFirstOccurrence(Object o)

参数:该方法接受一个强制参数 o ,该参数指定要从德克尔容器中移除的元素。

返回:该方法返回如果元素存在并从德格容器中移除,否则返回

注意:blocking equipmentremoveFirstOccurrence() 方法继承自 Java 中的 LinkedBlockingDeque 类。 以下程序说明了阻止请求的 removeFirstOccurrence()方法:

程序 1: 当元素存在时

Java 语言(一种计算机语言,尤用于创建网站)

// Java Program to demonstrate removeFirstOccurrence()
// method of BlockingDeque

import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.BlockingDeque;
import java.util.*;

public class GFG {
    public static void main(String[] args)
        throws InterruptedException
    {

        // create object of BlockingDeque
        BlockingDeque<Integer> BD
            = new LinkedBlockingDeque<Integer>();

        // Add numbers to end of BlockingDeque
        BD.add(15);
        BD.add(20);
        BD.add(20);
        BD.add(15);

        // print Deque
        System.out.println("Blocking Deque: " + BD);

        if (BD.removeFirstOccurrence(15))
            System.out.println("First occurrence of 15 removed");
        else
            System.out.println("15 not present and not removed");

        // prints the Deque after removal
        System.out.println("Blocking Deque: " + BD);
    }
}

Output

Blocking Deque: [15, 20, 20, 15]
First occurrence of 15 removed
Blocking Deque: [20, 20, 15]

程序 2: 当元素不存在时

Java 语言(一种计算机语言,尤用于创建网站)

// Java Program to demonstrate removeFirstOccurrence()
// method of BlockingDeque

import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.BlockingDeque;
import java.util.*;

public class GFG {
    public static void main(String[] args)
        throws InterruptedException
    {

        // create object of BlockingDeque
        BlockingDeque<Integer> BD
            = new LinkedBlockingDeque<Integer>();

        // Add numbers to end of BlockingDeque
        BD.add(15);
        BD.add(20);
        BD.add(20);
        BD.add(15);

        // print Deque
        System.out.println("Blocking Deque: " + BD);

        if (BD.removeFirstOccurrence(10))
            System.out.println("First occurrence of 10 removed");
        else
            System.out.println("10 not present and not removed");

        // prints the Deque after removal
        System.out.println("Blocking Deque: " + BD);
    }
}

Output: 

Blocking Deque: [15, 20, 20, 15]
10 not present and not removed
Blocking Deque: [15, 20, 20, 15]

参考:https://docs . Oracle . com/javase/7/docs/API/Java/util/concurrent/blocking request . html # removefirst occurrence(Java . lang . object)