链表实现队列Java

链表实现队列-Java

package MyQueue;

public class MyQueueLinked<Anytype> {
    private int theSize;
    private Node<Anytype> front;
    private Node<Anytype> back;

    class Node<Anytype> {
        private Anytype data;
        private Node<Anytype> next;

        public Node(Anytype x, Node<Anytype> next) {
            this.data = x;
            this.next = next;
        }
    }

    public int size() {
        return theSize;
    }

    public boolean isEmpty() {
        return theSize == 0;
    }

    public void enqueue(Anytype x) {
        Node<Anytype> newNode = new Node<>(x, null);
        if (size() == 0) {
            front = newNode;
            back = newNode;
        } else {
            back.next = newNode;
            back = newNode;
        }
        theSize++;
    }

    public Anytype dequeue() {
        if (size() == 0) {
            throw new IndexOutOfBoundsException("empty");
        }
        Anytype item = front.data;
        front = front.next;
        theSize--;
        return item;
    }

}

测试

package MyQueue;

public class MyQueueLinkedTest {
    public static void main(String[] args) {
        MyQueueLinked<String> myqueue = new MyQueueLinked<String>();
        myqueue.enqueue("a");
        myqueue.enqueue("b");
        myqueue.enqueue("c");
        myqueue.enqueue("d");
        myqueue.enqueue("e");

        System.out.println(myqueue.dequeue());
        System.out.println(myqueue.dequeue());
        System.out.println(myqueue.dequeue());
        System.out.println(myqueue.dequeue());
        System.out.println(myqueue.dequeue());
    }
}