MD5加密

1.

public class MD5Maker {

    public static String getMD5String(String str){ 
     try{ 
      byte psw[] = str.getBytes(); 
      MessageDigest md = MessageDigest.getInstance("MD5"); 
      md.update(psw); 
      return toHex(md.digest());
     } catch (Exception e) { 
            return null; 
        } 
    } 
     

    public static String toHex(byte buffer[]) { 
        StringBuffer sb = new StringBuffer(); 
        String s = null; 
        for (int i = 0; i < buffer.length; i++) { 
            s = Integer.toHexString((int) buffer[i] & 0xff); 
            if (s.length() < 2) { 
                sb.append('0'); 
            } 
            sb.append(s); 
        } 
        return sb.toString();
    }
}