boolean contains(Object o)
描述 (Description)
如果此deque包含指定的元素，则java.util.ArrayDeque.contains(Object)返回true 。
声明 (Declaration)
以下是java.util.ArrayDeque.contains()方法的声明
public boolean contains(Object o)
参数 (Parameters)
o - deque中包含的要检查的对象。
返回值 (Return Value)
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 (Exception)
NA
例子 (Example)
以下示例显示了java.util.ArrayDeque.contains（）方法的用法。
package com.iowiki;
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
