Here it comes...



package replace;

/**
 *

 */

import java.io.*;
public class Main {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        String mystring =" ";
    System.out.println("Enter the string");
     BufferedReader stdin = new BufferedReader( new InputStreamReader( System.in ) );
       
            try
            {
                mystring = stdin.readLine();
            } catch ( IOException e) { };
                               
       StringBuffer output =new StringBuffer(' ') ;
      
       for (int i=0;i<mystring.length();i++)
       {
          if (mystring.charAt(i)!=' ')
               output.append("*");
          else
               output.append(" ");
                       }
     System.out.println(output);
    }

}