java md5工具类

public class Md5Util{

public static String md5(String str){     String reStr = null;     try {         MessageDigest md5 = MessageDigest.getInstance("MD5");         byte[] bytes = md5.digest(str.getBytes());         StringBuffer stringBuffer = new StringBuffer();         for (byte b : bytes){             int bt = b&0xff;             if (bt < 16){                 stringBuffer.append(0);             }              stringBuffer.append(Integer.toHexString(bt));         }         reStr = stringBuffer.toString();     } catch (NoSuchAlgorithmException e) {         e.printStackTrace();     }     return reStr;  }   /*public static void main(String []orgs){    System.out.println(Md5Util.md5("123456"));}*/

}