安全机制MD5算法的JAVA包运用

 

java.security中的MessageDigest类有提供MD5和SHA算法.

 

import java.security.*;

/**

 *<p>Title:自助终端监控view4.0.0</p>

 *<p>Description:提供hashMD5算法加密</p>

 *<p>Copyright:Copyright(c)2006</p>

 *<p>Company:GRGBankingCo.,Ltd.</p>

 *@version1.0

 */

 

publicclass HashUtil

{

 privatestatic MessageDigest digest = null;

 

 public HashUtil()

 {

 }

//------------------------------------------------------------------------------

/**

 *对字符串进行HASH(MD5)加密，注意，加密结果不可逆

 

 *@paramdata待加密数据

 

 *@return加密结果

 */

 public synchronizedstaticfinal String hash(String data)

 {

      if (digest == null)

      {

        try

        {

          digest = MessageDigest.getInstance("MD5");

        }

        catch (NoSuchAlgorithmException nsae)

        {

          System.err.println("Failed to load the MD5 MessageDigest. ");

          nsae.printStackTrace();

        }

      }

      digest.update(data.getBytes());

      return encodeHex(digest.digest());

 }

//------------------------------------------------------------------------------

/**

 *将数组转换成16进制字符串

 

 *@parambytes

 *@return

 */

   publicstaticfinal String encodeHex(byte[] bytes)

   {

       StringBuffer buf = new StringBuffer(bytes.length * 2);

       for (int i = 0; i < bytes.length; i++)

       {

           if (((int) bytes[i] & 0xff) < 0x10)

           {

                   buf.append("0");

           }

           buf.append(Long.toString((int) bytes[i] & 0xff, 16));

       }

       return buf.toString();

    }

//------------------------------------------------------------------------------

}