代码实现：
package com.weyan;
import com.weyan.list.CircleLinkedList;
import com.weyan.list.List;
public class Deque<E> {
private List<E> list = new CircleLinkedList<>();
//元素个数
public int size() {
return list.size();
}
//队列是否为空
public boolean isEmpty() {
return list.isEmpty();
}
//从队尾入队
public void enQueueRear(E element) {
list.add(element);
}
//从队尾出队
public E deQueueRear() {
return list.remove(list.size()-1);
}
//从队头入队
public void enQueueFront(E element) {
list.add(0, element);
}
//从队头出队
public E deQueueFront() {
return list.remove(0);
}
//队头元素
public E front() {
return list.get(0);
}
//队尾元素
public E rear() {
return list.get(list.size()-1);
}
}
验证结果：
