MD5 Ecrypt with Java

[sde]

What is the say to MD5 encrypt a string with Java?

[Belisarius]

You can use the javax.crypto package, or you can download and use this LGPL package, which I prefer because it'll spit back hex instead of bytes.

[sde]

well here is what i came up with after searching, .. but i want it to be like the 32 character hash that the php md5() function creates.

public static String encryptString(String str){
    byte[] originalByteArray = str.getBytes();
    String returnString = "";
    
    try{      
      MessageDigest digest = MessageDigest.getInstance("MD5");
      digest.reset();
      digest.update(originalByteArray);
      byte[]arr = digest.digest();
      returnString = arr.toString();
      
    }catch(Exception e){
      System.out.println("Error:encryptString()");
      return returnString;
    }
    
    return returnString;
  }

[sde]

oops, .. posted at the same time .. thanks i'll check that out.

[sde]

ok, well here is answers i found in another forum regarding making the hash look exactly like php:

MD5 is a 128-bit hash.
128 / 8 = 16 bytes
16 bytes, converted to hexadecimal, will give 32 characters.
So convert your MD5 output to hexadecimal

import java.util.*;
import java.io.*;
import java.security.*;
public class Test  {    
    public static String hex(byte[] array) {        
        StringBuffer sb = new StringBuffer();        
        for (int i = 0; i < array.length; ++i) {            
            sb.append(Integer.toHexString((array[i] & 0xFF) | 0x100).toUpperCase().substring(1,3));        
        }        
        return sb.toString();    
    }    
    public static String md5 (String message) {         
        try {             
            MessageDigest md = MessageDigest.getInstance("MD5");             
            return hex (md.digest(message.getBytes("CP1252")));         
        } catch (NoSuchAlgorithmException e) {         
        } catch (UnsupportedEncodingException e) {         
        }         
        return null;    
    }    
    public static void main(String[] args) {        
        System.out.println (md5 ("Hello, world!"));    
    }
}

[SpaceMonkey]

If you remove the .toUpperCase(). portion of the code in the hex() function, then the output of the hashing function will be compatible with the output format of Unix/Linux versions of md5sum as well as this JavaScript function for computing MD5 hashes client side (for implementing CHAP login systems)

[sde]

oh nice! finding the javascript version has been in the back of my mind for a while now. thanks space!