Java.util.ArrayDeque.contains(Object) Java.util.ArrayDeque.clone() Java.util.ArrayDeque.descendingIterator() 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 Java.util.ArrayDeque.clone() Java.util.ArrayDeque.descendingIterator()