macmd5.java

java web模拟的简单的一个网络硬盘

package com.dark.comm.util;

/**
 * 利用java内置包实现MD5算法 并把其结果转化为字符串（共32个字符）
 */
public class MacMD5 {
  private byte[] digesta;

  public String CalcMD5(String myinfo) {
    try {
      java.security.MessageDigest alga = java.security.MessageDigest
          .getInstance("MD5");
      alga.update(myinfo.getBytes());
      digesta = alga.digest();
    }
    catch (java.security.NoSuchAlgorithmException ex) {
      System.out.print("生成非法摘要算法错误：");
      System.out.println(ex);
    }
    return byte2hex(digesta);
  }

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