package webraveler.util;

import java.io.*;
import java.security.*;
 
/**
 * A simple little class for making generating MD5 hashes
 * of usernames -- for storing in password files -- easier.
 * 
 * @author martinsa
 */
public class MD5Helper  {
	
	/**
	 * Returns the byte array as a hex string.
	 * 
	 * @param array
	 * @return
	 */
    private static String getHexString(byte[] array) {
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < array.length; i++) {
            sb.append(Integer.toHexString((array[i] & 0xFF) | 0x100).substring(1,3));
           // sb.append(Integer.toHexString((array[i])));
        }//for
        return sb.toString();
    }//String getHexString(byte[])
    
    
    /**
     * Returns the MD5 hash, as a hex string, of the given
     * message.
     * 
     * @param message
     * @return
     */
    public static String md5 (String message) throws Exception { 
        try { 
            MessageDigest md = MessageDigest.getInstance("MD5"); 
            return getHexString(md.digest(message.getBytes(System.getProperty("file.encoding"))));
        } catch (NoSuchAlgorithmException e) { 
        } catch (UnsupportedEncodingException e) { 
        } 
        
        throw new Exception ("md5: Error getting md5 hash!");
    }//static String md5(String)
    
    /**
     * Print a few sample MD5 hashes to stdout
     * 
     * @param args
     */
    public static void main(String[] args) {
    	try { 
    		System.out.println (md5 ("biatch") + "  biatch");
    		System.out.println (md5 ("sam") + "  sam");
    	} catch (Exception e) {}
    }//static void main
    
}//class MD5Helper