栈实现分隔符匹配

package com.liu.Stack;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

import org.junit.Test;

public class BracketChecker {
    private String input;
    public BracketChecker(String in)
    {
        input = in;
    }
        
    public void check()
    {
        int stackSize = input.length();
        StackX11 theStack = new StackX11(stackSize);
        
        for(int j=0;j<input.length();j++)
        {
            char ch = input.charAt(j);
            switch(ch)
            {
            case '{':
            case '[':
            case '(':
                theStack.push(ch);
                break;
                
            case '}':
            case ']':
            case ')':
                if(!theStack.isEmpty())
                {
                    char chx = theStack.pop();
                    if((ch=='}'&&chx!='{') ||
                    (ch==')'&&chx!='(') ||
                    (ch==']'&&chx!='['))
                        System.out.println("error:"+ch+" at "+j);
                }
                else
                    System.out.println("error:"+ch+"at"+j);
                break;
                
            default:
                break;
            }
        }
        if(!theStack.isEmpty())
            System.out.println("error!");
        else
            System.out.println("success!");
    }
}

class StackX11
{
    private int maxsize;
    private char[] stackArray;
    private int top;
    
    public StackX11(int maxsize)
    {
        this.maxsize = maxsize;
        stackArray = new char[this.maxsize];
        top=-1;
    }
    
    public void push(char c)
    {
        stackArray[++top] = c;
    }
    
    public char pop()
    {
        return stackArray[top--];
    }
    
    public char peek()
    {
        return stackArray[top];
    }
    
    public boolean isEmpty()
    {
        if(top==-1)
            return true;
        else
            return false;
            
    }
}

class BracketsApp
{
    
    public static void main(String[] args) throws IOException
    {
        String input;
        while(true)
        {
            System.out.print("enter string containing delimiters:");
            System.out.flush();
            input = getString();
            if(input.equals(""))
                break;
            BracketChecker theChecker = new BracketChecker(input);
            theChecker.check();
        }
        
        
        
    }
    
    public static String getString() throws IOException
    {
        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        String s = br.readLine();
        return s;
    }
    
}