Java.util.ArrayDeque.contains（Object）

描述

该java.util.ArrayDeque.contains（对象）返回真，如果此双端队列包含指定的元素。

声明

以下是java.util.ArrayDeque.contains（）方法的声明

public boolean contains(Object o)

参数

o - deque中包含的要检查的对象。

返回值

如果此双端队列包含指定的元素，则此方法返回true，否则返回false。

异常

NA

实例

以下示例显示了java.util.ArrayDeque.contains（）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);
      deque.add(18);        

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

      // deque contains element 10
      boolean retval = deque.contains(10);

      if (retval == true) {
         System.out.println("element 10 is contained in the deque");
      } else {
         System.out.println("element 10 is not contained in the deque");
      }

      // deque does not contain element 25
      boolean retval2 = deque.contains(25);

      if (retval2 == true) {
         System.out.println("element 25 is contained in the deque");
      } else {
         System.out.println("element 25 is not contained in the deque");    
      }
   }
}

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
Number = 18
element 10 is contained in the deque
element 25 is not contained in the deque