java自定义堆栈

package com.zhb.corejava.util;
public class Stack<E> {
	private E[] elementData;
	private int top;
	
	private int count;
	
	@SuppressWarnings("unchecked")
	public Stack(int size) {
		this.elementData = (E[]) new Object[size];
		top = -1;
		count = 0;
	}
	public Stack() {
		this(10);
	}
	
	/**
	 * 返回堆栈长度
	 * @return
	 */
	public int getSize(){
		return elementData.length;
	}
	
	/**
	 * 返回栈中元素的个数
	 * @return
	 */
	public int getElementCount() {
		return count;
	}
	
	/**
	 * 判栈空
	 * @return
	 */
	public boolean isEmpty(){
		return top == -1;
	}
	
	/**
	 * 判栈满
	 * @return
	 */
	public boolean isFull(){
		return top == (elementData.length-1);
	}
	
	/**
	 * 入栈操作
	 * @param object
	 */
	public void push(E object){
		if(isFull()){
			throw new RuntimeException("栈已经满");
		}else{
			elementData[++top] = object;
			count++;
		}
	}
	
	/**
	 * 出栈操作，并返回被出栈的元素
	 * @return
	 */
	public E pop(){
		if(isEmpty()){
			throw new RuntimeException("栈是空的");
		}else{
			count--;
			return elementData[top--];
		}
	}
/**
	 * 返回栈顶元素
	 * @return
	 */
	public E peek(){
		if(isEmpty()){
			throw new RuntimeException("栈是空的");
		}else{
			return elementData[top];
		}
	}
}

编写测试类：

package com.zhb.corejava.util;
public class ClientTest {
	public static void main(String[] args) {
		Stack<User> stack = new Stack<User>();
		User user1 = new User("张三", 1);
		User user2 = new User("李四", 2);
		User user3 = new User("王五", 2);
		stack.push(user1);
		stack.push(user2);
		stack.push(user3);
		System.out.println("stack.size====" + stack.getSize());
		User user = stack.pop();
		System.out.println("user.name==1==" + user.getName());
		System.out.println("-------------------------------------------");
		user = stack.pop();
		System.out.println("user.name==2==" + user.getName());
		System.out.println("-------------------------------------------");
		user = stack.pop();
		System.out.println("user.name==3==" + user.getName());
		
		System.out.println("stack.size====" + stack.getSize());
		
		System.out.println("-------------------------------------------");
		
		stack.push(user1);
		
		System.out.println("stack.size====" + stack.getSize());
		
		System.out.println("stack.isEmpty==="+stack.isEmpty());
		System.out.println("stack.isFull==="+stack.isFull());
	}
}