使用java实现栈

public class StackTest<T> {
    public static class Node<U>{
        public U item;
        public Node next;
        public Node() {
            this.item = null;
            this.next = null;
        }
        public Node(U item, Node<U> next) {
            this.item = item;
            this.next = next;
        }
        public boolean end() {
            return item == null && next == null;
        }
    }

    private Node<T> top = new Node<T>();

    public void push(T item) {
        top = new Node<T>(item, top);
    }

    public T pop() {
        T result = top.item;
        if (!top.end()) {
            top = top.next;
        }
        return result;
    }

    public static void main(String[] args) {
        StackTest<String> st = new StackTest<>();
        for (String str : "I love java".split(" ")) {
            st.push(str);
        }
        while (!st.top.end()) {
            System.out.println(st.pop());
        }
    }


}