数据结构之栈

栈的原理：先进后出，类似枪夹的子弹，先进的子弹后出。具体代码构建一个栈如下：

/**
 * 
<p>Title:MyStack </p>
<p>Description:栈的应用 </p>
<p>Company: </p>
 * @author ll
 * @date 2017-10-24 下午22:01:57
 *
 */
public class MyStack{
    //底层数组实现
    private long []arr;
    private int top;//栈顶
   //默认的构造器
    public MyStack(){
    //初始化数组大小
       arr = new long[10];
       top = -1;
    }
    //带参数的构造器
    public MyStack(int maxSize){
       arr = new long[maxSize];
       top = -1;
    }
    /**
     * 
    * @Title:push
    * @Description:入栈
    * @param @param value
    * @return void
    * @throws
     */
    public void push(long value){
       arr[++top] = value;
    }
    /**
     * 
    * @Title:pop
    * @Description:出栈
    * @param @return
    * @return long
    * @throws
     */
    public long pop(){
       return arr[top--];
    }
    /**
     * 
    * @Title:peek
    * @Description:查询栈元素
    * @param @return
    * @return long
    * @throws
     */
    public long peek(){
       return arr[top];
    }
    /**
     * 
    * @Title:isEmpty
    * @Description:判断是否为空
    * @param @return
    * @return boolean
    * @throws
     */
    public boolean isEmpty(){
       return top == -1;
    }
    /**
     * 
    * @Title:isFull
    * @Description:判断是否满了
    * @param @return
    * @return boolean
    * @throws
     */
    public boolean isFull(){
       return arr[top] == arr.length - 1;
    }
}

测试类如下：
package com.ll.dataStructTest;

import org.junit.Test;

import com.ll.dataStruct.MyStack;
/**
 * 
<p>Title:TestMyStack </p>
<p>Description:测试栈的一些方法 </p>
<p>Company: </p>
 * @author ll
 * @date 2017-10-24 下午22:03:43
 *
 */
public class TestMyStack {
    @Test
    public void testStack(){
        MyStack myStack = new MyStack(6);
        myStack.push(22);
        myStack.push(43);
        myStack.push(33);
        myStack.push(3);
        myStack.push(12);
        myStack.push(143);
        System.out.println(myStack.isEmpty());
        System.out.println(myStack.isFull());
        System.out.println(myStack.peek());
        while(!myStack.isEmpty()){
            System.out.print(myStack.pop() + ",");

        }
    }
}