java BlockingDeque element()方法及示例
BlockingDeque 的 element() 方法返回容器中最前面的元素。它不会删除容器中的元素。这个方法返回这个deque所代表的队列的头部。
语法
public void element()
参数: 该方法不接受任何参数。
返回: 该方法返回该deque所代表的队列的头部。
注意 : BlockingDeque 的element()方法是继承自Java中的LinkedBlockingDeque类。
下面的程序说明了BlockingDeque的element()方法。
程序1 :
// Java Program Demonstrate element()
// method of BlockingDeque
import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.BlockingDeque;
import java.util.*;
public class GFG {
public static void main(String[] args)
throws IllegalStateException
{
// create object of BlockingDeque
BlockingDeque<Integer> BD
= new LinkedBlockingDeque<Integer>();
// Add numbers to end of BlockingDeque
BD.add(10);
BD.add(20);
BD.add(30);
BD.add(40);
// before removing print Deque
System.out.println("Blocking Deque: " + BD);
System.out.println("Blocking Deque front element: " + BD.element());
}
}
输出
Blocking Deque: [10, 20, 30, 40]
Blocking Deque front element: 10
程序2 :
// Java Program Demonstrate element()
// method of BlockingDeque
import java.util.concurrent.LinkedBlockingDeque;
import java.util.*;
import java.util.concurrent.BlockingDeque;
public class GFG {
public static void main(String[] args)
throws IllegalStateException
{
// create object of BlockingDeque
BlockingDeque<String> BD
= new LinkedBlockingDeque<String>();
// Add numbers to end of BlockingDeque
BD.add("ab");
BD.add("cd");
BD.add("fg");
BD.add("xz");
// before removing print Deque
System.out.println("Blocking Deque: " + BD);
System.out.println("Blocking Deque front element: " + BD.element());
}
}
输出
Blocking Deque: [ab, cd, fg, xz]
Blocking Deque front element: ab
**参考资料: **https: //docs.oracle.com/javase/7/docs/api/java/util/concurrent/BlockingDeque.html#element()