Md5加密及二进制转换

package cn.com.md.ocean.share.crypt;
import java.security.*;

public class Md5 {
  public Md5() {
  }

  public static String byte2hex(byte[] b) { //二行制转字符串
    String hs = "";
    String stmp = "";
    for (int n = 0; n < b.length; n++) {
      stmp = (Integer.toHexString(b[n] & 0XFF));
      if (stmp.length() == 1)
        hs = hs + "0" + stmp;
      else
        hs = hs + stmp;
      if (n < b.length - 1)
        hs = hs;
    }
    return hs.toUpperCase();
  }

  public static String getMD5(String password) {
    String returnStr = null;
    try {
      java.security.MessageDigest alga = java.security.MessageDigest.
          getInstance("MD5");

      alga.update(password.getBytes());
      byte[] digesta = alga.digest();
      returnStr = byte2hex(digesta);
    }
    catch (Exception e) {}
    return returnStr;
  }

  public static void main(String args[]) {

    Md5 m = new Md5();

    System.out.println("MD5 Test suite:");
    System.out.println("MD5(\"\"):" + m.getMD5(""));
    System.out.println("MD5(\"a\"):" + m.getMD5("a"));
    System.out.println("MD5(\"abc\"):" + m.getMD5("abc"));
    System.out.println("MD5(\"message digest\"):" + m.getMD5("message digest"));
    System.out.println("MD5(\"abcdefghijklmnopqrstuvwxyz\"):" +
                       m.getMD5("abcdefghijklmnopqrstuvwxyz"));
    System.out.println(
        "MD5(\"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789\"):" +
        m.getMD5(
        "admin"));

  }

}