Java ArrayBlockingQueue remainingCapacity()用法及代码示例

ArrayBlockingQueue是有界的阻塞队列，该队列内部使用数组支持的元素存储。

ArrayBlockingQueue类是Java Collections Framework的成员。
有界意味着它将具有固定的大小，您不能存储数量超过队列容量的元素。
队列还遵循FIFO(先进先出)规则，用于存储和删除队列中的元素。
如果您尝试将一个元素放入一个完整的队列或从一个空队列中取出一个元素，那么该队列将阻塞。

remainingCapacity()方法返回可以添加到队列而不会阻塞的更多元素的数量。这始终等于此队列的初始容量与该队列的当前大小之差。

用法:

public int remainingCapacity()

参数：该方法不带任何参数。

返回值：该方法返回队列的剩余容量。

以下示例程序旨在说明ArrayBlockingQueue的remainingCapacity()方法：
示例1:

// Program to demonstrate remainingCapacity() method 
// of ArrayBlockingQueue 
  
import java.util.concurrent.ArrayBlockingQueue; 
  
public class GFG { 
  
    public static void main(String[] args) 
    { 
        // Define capacity of ArrayBlockingQueue 
        int capacity = 5; 
  
        // Create object of ArrayBlockingQueue 
        ArrayBlockingQueue<Integer> queue = new 
            ArrayBlockingQueue<Integer>(capacity); 
  
        // Add elements to ArrayBlockingQueue 
        queue.add(23); 
        queue.add(32); 
  
        // Print queue after adding numbers 
        System.out.println("Queue :" + queue); 
        // Check remaining capacity 
        int remainingCapacity = queue.remainingCapacity(); 
        System.out.println("Remaining Capacity:" +  
                                       remainingCapacity); 
  
        // Add elements to ArrayBlockingQueue 
        queue.add(54); 
        queue.add(78); 
  
        // Print queue after adding numbers 
        System.out.println("Queue :" + queue); 
        // Check remaining capacity 
        System.out.println("Remaining Capacity:" +  
                               queue.remainingCapacity()); 
    } 
}

输出：

Queue :[23, 32]
Remaining Capacity:3
Queue :[23, 32, 54, 78]
Remaining Capacity:1

示例2:

// Program to demonstrate remainingCapacity() method 
// of ArrayBlockingQueue 
  
import java.util.concurrent.ArrayBlockingQueue; 
  
public class GFG { 
    // Create a User Object with name and age as an attribute 
    public class User { 
  
        public String name; 
        public String age; 
        User(String name, String age) 
        { 
            this.name = name; 
            this.age = age; 
        } 
    } 
  
    // Main Method 
    public static void main(String[] args) 
    { 
        GFG gfg = new GFG(); 
        gfg.RemainingCapacityExample(); 
    } 
    // Method to give example of contains function 
    public void RemainingCapacityExample() 
    { 
  
        // Define capacity of ArrayBlockingQueue 
        int capacity = 5; 
  
        // Create object of ArrayBlockingQueue 
        ArrayBlockingQueue<User> queue = new 
                  ArrayBlockingQueue<User>(capacity); 
  
        // Create user objects 
        User user1 = new User("Aman", "24"); 
        User user2 = new User("Amar", "23"); 
        User user3 = new User("Sanjeet", "25"); 
  
        // Add Objects to ArrayBlockingQueue 
        queue.offer(user1); 
        queue.offer(user2); 
        queue.offer(user3); 
  
        // Check remaining capacity 
        int remainingCapacity = queue.remainingCapacity(); 
        System.out.println("Remaining Capacity:" +  
                                       remainingCapacity); 
  
        User user4 = new User("Suvo", "26"); 
        User user5 = new User("Ravi", "22"); 
          
        // Adding more objects 
        queue.offer(user2); 
        queue.offer(user3); 
  
        // Check remaining capacity 
        remainingCapacity = queue.remainingCapacity(); 
        System.out.println("Remaining Capacity:" +  
                                     remainingCapacity); 
    } 
}

输出：

Remaining Capacity:2
Remaining Capacity:0

参考： https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/ArrayBlockingQueue.html#remainingCapacity()

相关用法

注：本文由纯净天空筛选整理自AmanSingh2210大神的英文原创作品 ArrayBlockingQueue remainingCapacity() Method in Java。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。