Java Java.util.ArrayDeque.clear()用法及代码示例

描述

这个java.util.ArrayDeque.clear()方法从中删除所有元素deque。

声明

以下是声明java.util.ArrayDeque.clear()方法

public void clear()

参数

NA

返回值

此方法不返回任何值。

异常

NA

示例

下面的例子展示了 java.util.ArrayDeque.clear() 方法的用法。

package com.tutorialspoint;

import java.util.ArrayDeque;
import java.util.Deque;

public class ArrayDequeDemo {
   public static void main(String[] args) {
     
      // create an empty array deque with an initial capacity
      Deque<Integer> deque = new ArrayDeque<Integer>(8);

      // use add() method to add elements in the deque
      deque.add(20);
      deque.add(30);
      deque.add(10);

      // let us print all the elements available in deque
      for (Integer number:deque) {
         System.out.println("Number = " + number);
      }      

      // finding size of this deque
      int retval = deque.size();
      System.out.println("Deque consists of "+ retval +" elements");

      System.out.println("Performing clear operation !!");
      deque.clear();
      retval = deque.size();
      System.out.println("Now, deque consists of "+ retval +" elements");
   }
}

让我们编译并运行上面的程序，这将产生以下结果——

Number = 20
Number = 30
Number = 10
Deque consists of 3 elements
Performing clear operation !!
Now, deque consists of 0 elements