4 java两栈共享空间

package com.java.datastructure.stact;
//java两栈共享空间
public class ShareLinearStact {
    private final static   int defSize = 2;
    private int top1 = -1;
    private int top2 = defSize;
    private String[] data = new String [defSize];

    //添加元素
    public boolean push(String pData,  int type) {
        //判断是否栈满
        if(top1+1 ==top2) {
            System.out.println("栈满了。。。");
            return false;
        }
        //
       if(type==1) {
            top1++;
           data[top1] = pData;
       } else if (type==2) {
            top2 --;
            data[top2] = pData;
        }
        return true;
    }

    //取出元素
    public String pop(int type) {
        //判断是否栈满
        if(isEmpt()) {
            return null;
        }
       String temp = null;
        if(type==1) {
            temp = data[top1];
            data[top1] = null;
            top1--;
        } else if (type==2) {
            temp = data[top2];
            data[top2] = null;
            top2++;
        }

        return temp;
    }

    //删除元素
    public boolean del(int type) {
        if(isEmpt()) {
            return false;
        }
       if(type==1) {
           data[top1] = null;
           top1--;
       } else if (type==2) {
           data[top2] = null;
           top1++;
        }
        return true;
    }

    //获取栈顶元素
    public String peek1() {
        if(top1==-1) {
            return null;
        } else {
            return data[top1];
        }
    }

    //获取栈顶元素
    public String peek2() {
        if(top2==defSize) {
            return null;
        } else {
            return data[top2];
        }
    }

//    //查找元素
//    public int search(String content) {
//            int index = -1;
//            for (int i=0; i<length(); i++) {
//                    if(data[i].equals(content)) {
//                        index = i;
//                        break;
//                    }
//            }
//            return index;
//    }

    public void resize() {
        String[] dataTemp = new String [data.length*2];
        for (int i=0; i<data.length; i++) {
            dataTemp [i] = data[i];
            data[i] = null;
        }
        data = dataTemp;
        dataTemp = null;
    }

    //判断是否为空
    public boolean isEmpt() {
        return top1==-1 && top2==defSize;
    }

    //获取栈  实际元素个数
    public int length() {
        //top1栈元素
        Integer t1 = top1+1;
        Integer t2 = defSize-top2;
        return t1+t2;
    }

    //清除
    public void clean() {
        for (int i=0; i<data.length; i++) {
             data[i] = null;
        }
        top1 = -1;
        top2 = defSize;
    }

    public void display() {
        for (int i=0; i<data.length; i++) {
           System.out.println("打印每个元素"+data[i]);
        }
    }

    public static  void main(String[] args)  {
        ShareLinearStact stact = new ShareLinearStact();
        String content = "isNull  ";
        System.out.println(content+"判断是否为空  "+stact.isEmpt());
        System.out.println(content+"获取栈顶元素  "+stact.pop(1));
        System.out.println(content+"获取元素个数  "+stact.length());
        System.out.println(content+"获取栈顶-peak元素  "+stact.peek1());
        //System.out.println(content+"获取查找stactA元素  "+stact.search("stactA"));



        stact.push("stactA",1);
        stact.push("stactB",1);
        stact.push("stactC",2);

        //打印
        stact.display();

        content = "notNull  ";
        System.out.println(content+"判断是否为空  "+stact.isEmpt());
        System.out.println(content+"获取元素个数  "+stact.length());
        System.out.println(content+"获取栈顶-peak1-元素  "+stact.peek1());
        System.out.println(content+"获取栈顶-peak2-元素  "+stact.peek2());
    }
}