Java 中的 BlockingDeque add()方法,示例

原文:https://www . geeksforgeeks . org/blocking reque-add-method-in-Java-with-examples/

add(E e) 方法 blocking eque将参数中传递的元素插入到有空格的 Deque 的末尾。如果阻塞请求受到容量限制并且没有空间可供插入,它将返回一个非法状态异常。它的工作方式与 addLast()方法完全相同。

语法:

public void add(E e)

参数:该方法接受一个强制参数 e ,它是要插入到阻塞请求末尾的元素。

返回:这个方法不返回任何东西。

异常:

  • [T0】 illegalstatexception 【T1]: If the element cannot be added due to capacity limitation at this time.
  • [T0】 NullPointerException 【T1]: If the specified element is empty.

:blocking eque的 add()方法继承了 Java 中的link edblocking eque类。

下面的程序说明了添加()的方法:

程序 1:

// Java Program Demonstrate add()
// 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 IllegalStateException
    {

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

        // Add numbers to end of BlockingDeque
        BD.add(7855642);
        BD.add(35658786);
        BD.add(5278367);
        BD.add(74381793);

        // before removing print queue
        System.out.println("Blocking Deque: " + BD);
    }
}

输出:

Blocking Deque: [7855642, 35658786, 5278367, 74381793]

节目 2:

// Java Program Demonstrate add()
// method of BlockingDeque
// when it is Full
import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.BlockingDeque;
import java.util.*;

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

        // create object of BlockingDeque
        // size of list
        BlockingDeque<Integer> BD
            = new LinkedBlockingDeque<Integer>(3);

        // Add numbers to end of BlockingDeque
        BD.add(7855642);
        BD.add(35658786);
        BD.add(5278367);

        // it is full
        BD.add(74381793);

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

输出:

Exception in thread "main" java.lang.IllegalStateException: Deque full
    at java.util.concurrent.LinkedBlockingDeque.addLast(LinkedBlockingDeque.java:335)
    at java.util.concurrent.LinkedBlockingDeque.add(LinkedBlockingDeque.java:633)
    at GFG.main(GFG.java:24)

节目 3:

// Java Program Demonstrate add()
// method of BlockingDeque
// when null is inserted

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

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

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

        // Add numbers to end of BlockingDeque
        BD.add(7855642);
        BD.add(35658786);
        BD.add(5278367);

        // NULL
        BD.add(null);

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

输出:

Exception in thread "main" java.lang.NullPointerException
    at java.util.concurrent.LinkedBlockingDeque.offerLast(LinkedBlockingDeque.java:357)
    at java.util.concurrent.LinkedBlockingDeque.addLast(LinkedBlockingDeque.java:334)
    at java.util.concurrent.LinkedBlockingDeque.add(LinkedBlockingDeque.java:633)
    at GFG.main(GFG.java:23)

参考:https://docs . Oracle . com/javase/7/docs/API/Java/util/concurrent/blockingdequee . html # add(E)