Java实现栈之计算器

Java实现栈来做一个将中缀表达式转化为后缀表达式的程序，中缀表达式更符合我们的主观感受，后缀表达式更适合计算机的运算，下面直接上代码吧：

package Character1;

import java.util.Stack;

public class Calculter {

    private static Stack<Object> shu = new Stack<Object>();
    private static Stack<Object> fu = new Stack<Object>();
    static String oldString = "(1+2)+2*(4-1)+6/3";

    public static void main(String[] args) {
        char[] chars = new char[oldString.length()];
        for (int i = 0; i < oldString.length(); i++) {
            chars[i] = oldString.charAt(i);
        }
        for (int i = 0; i < chars.length; i++) {
            if (isCaoZuoFu(chars[i])) {
                if (chars[i] == '(') {
                    fu.add(chars[i]);
                }
                if (chars[i] == ')') {
                    // System.out.println(fu);
                    while ((char) fu.peek() != '(') {
                        shu.add(fu.pop());
                    }
                    if ((char) fu.peek() == '(') {
                        fu.pop();
                    }
//                  System.out.println(fu+"-----");
                    while (fu.isEmpty() != true) {
                        char temp = (char) fu.pop();
                        fu.add(temp);
                        if (temp == '*' || temp == '/') {
                            shu.add(temp);
                            fu.pop();
                        } else {
                            break;
                        }
                    }
                } else if (chars[i] == '*') {
                    fu.add(chars[i]);
                } else if (chars[i] == '/') {
                    fu.add(chars[i]);
                } else if (chars[i] == '+') {
                    fu.add(chars[i]);
                } else if (chars[i] == '-') {
                    fu.add(chars[i]);
                }
            } else {
                shu.add(chars[i]);
            }
        }
//      System.out.println(fu.toString());
//      System.out.println(shu.toString());
        System.out.println("原字符串是："+oldString);
        System.out.println("------------------以上部分千万不要改动了");
        while(fu.isEmpty()!=true){
            shu.add(fu.pop());
        }
        System.out.println("操作符栈："+fu.toString());
        System.out.println("操作数栈："+shu.toString());
        System.out.println("----------------------中缀表达式转换为后缀表达式的结果！");
        int result=JiSuan(Reverse(shu));
        System.out.println("表达式最终答案："+result);
    }


    public static int JiSuan(Stack<Object> stack){
        int result=0;
        Stack<Object>temp=new Stack<Object>();//存放后缀表达式的操作数的栈
        while(stack.isEmpty()!=true){
            if(!isCaoZuoFu((char)stack.peek())){
                temp.add(stack.pop());
                System.out.println(temp);
            }else{
                int o1=Integer.parseInt(temp.pop().toString());
                int o2=Integer.parseInt(temp.pop().toString());
                if(stack.isEmpty()!=true){
                    if((char)stack.peek()=='+'){
                        temp.add(o2+o1);
                    }
                    if((char)stack.peek()=='-'){
                        temp.add(o2-o1);
                    }
                    if((char)stack.peek()=='*'){
                        temp.add(o2*o1);
                    }
                    if((char)stack.peek()=='/'){
                        temp.add(o2/o1);
                    }
                    stack.pop();
                }
            }
        }
        return (int) temp.peek();
    }

    public static Stack<Object> Reverse(Stack<Object> shu){
        Stack<Object> reverseStack=new Stack<Object>();
        while(shu.isEmpty()!=true){
            reverseStack.add(shu.pop());
        }
        System.out.println("来个反序："+reverseStack);
        return reverseStack;
    }
    //此方法用于判断对应字符是不是操作符，其中case的数字是对应的ASCII码。
    public static boolean isCaoZuoFu(char b) {
        int temp = (char) b;
        switch (temp) {
        case 43:
        case 45:
        case 42:
        case 47:
        case 40:
        case 41:
            return true;
        default:
            return false;
        }
    }

}

下面就是程序的运行结果：

由于时间匆忙，未来得及做注释，导致此程序可读性较差，还望读者取精华弃糟粕。也希望对我的书写中有错误的地方予以指正，旨在我们的共同进步！