md5加密

将加密后的数据转换为16进制32位的字符串：

private static final char HEX_DIG[]={'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'}; public static void main(String[] args) throws Exception{ //初始化加密器 MessageDigest md5 = MessageDigest.getInstance("MD5"); //获取字节数组 byte[] resource = "123".getBytes(); //得到加密后的字节数组 byte[] result = md5.digest(resource); //转化为16进制32位的字符串 System.out.println(getHexString(result)); } static String getHexString(byte[] b){ StringBuilder sb = new StringBuilder(); for(int i= 0; i<b.length;i++){ sb.append( HEX_DIG[b[i]& 0xf0 >>>4]); sb.append( HEX_DIG[b[i]& 0x0f]); } return sb.toString(); }

密码和一段字符串相加进行编码可增加破解的难度：

private static final String key = "282328392839283928"; public static String md5(String password){ try { MessageDigest md = MessageDigest.getInstance("md5"); //密码和字符串相加增加破解的难度 byte md5[] = md.digest((key+password).getBytes()); //进行BASE64编码 BASE64Encoder base64 = new BASE64Encoder(); //明文字符串 return base64.encode(md5); } catch (NoSuchAlgorithmException e) { throw new RuntimeException(e); } }