md5codejava.java

一个MD5加密解密算法程序,可以实现加密解密的功能.

package com.hjhm.functions;
import java.security.MessageDigest;
/**
* <p>Title:MD5Encode </p>
* <p>Description: 用于实现md5加密算法的类</p>
* <p>Copyright: Copyright (c) 2003</p>
* <p>Company: hjhm</p>
* @author lyzcw
* @version 1.0
*/

public class MD5Encode {
    public MD5Encode() {
    }

    private final static String[] hexDigits = {
    "0", "1", "2", "3", "4", "5", "6", "7",
    "8", "9", "a", "b", "c", "d", "e", "f"};

/**
  * 转换字节数组为16进制字串
  * @param b 字节数组
  * @return 16进制字串
  */

public static String byteArrayToHexString(byte[] b) {
  StringBuffer resultSb = new StringBuffer();
  for (int i = 0; i < b.length; i++) {
    resultSb.append(byteToHexString(b[i]));
  }
  return resultSb.toString();
}

private static String byteToHexString(byte b) {
  int n = b;
  if (n < 0)
    n = 256 + n;
  int d1 = n / 16;
  int d2 = n % 16;
  return hexDigits[d1] + hexDigits[d2];
}

public static String MD5(String origin) {
  String resultString = null;

  try {
    resultString=new String(origin);
    MessageDigest md = MessageDigest.getInstance("MD5");
    resultString=byteArrayToHexString(md.digest(resultString.getBytes()));
  }
  catch (Exception ex) {

  }
  return resultString;
}

}