Please wat is wrong with this program

Question

I want to reverse the user input but when I run this program it only asks for the input and when i key it in and press enter nothing happens.It just freezes.
Sorry the code is a bit long .
import java.io.*;
class StackX
private int maxSize;
private char[] stackArray;
private int top;
public StackX(int max)  
       maxSize=max;
       stackArray=new char[maxSize];
       top=-1;
public void push(char j) 
     stackArray[++top]=j;
public char pop()    
     return stackArray[top--];
public char peek()  
     return stackArray[top];
public boolean isEmpty()   
     return (top==-1);
class Reverser
     private String input;  
     private String output; 
public Reverser(String in)
     {input = in;}
         public String doRev( )    
     int stackSize=input.length( ); 
     StackX theStack = new StackX(stackSize);
     for(int j=0;j<input.length( );j++)
     char ch=input.charAt(j); 
     theStack.push(ch);
     output ="";
     while( !theStack.isEmpty() )
     char ch=theStack.pop();
     output=output+ch; 
     return output;
class ReverseApp
     public static void main(String[]args)throws IOException
     String input, output;
     while(true)
     System.out.print("Enter a string:");
     System.out.flush();
     input=getString();
     if( input.equals(""))
      break;
     Reverser theReverser = new Reverser(input);
     output = theReverser.doRev();
     System.out.println("Reversed: " + output);
public static String getString()throws IOException
     InputStreamReader isr = new InputStreamReader(System.in);
     BufferedReader br= new BufferedReader(isr);
     String s = br.readLine();
     return s;
}

Answer 1

One potential problem is that you're using a new reader around system.in every time. I don't know what happens when you do that. Just make it a member variable, or create it once in main and pass it to getString.
Asid from that, put a bunch of print statements in or use a debugger to see what's happening at each step of the way. You might be getting into an infinite loop somewhere in your reverse operation.