JavaMD5加密

D5加密

    public class DataprocessUtils {
        /**
         * MD5加密
         * @param source 明文
         * @return 密文
         */
        public static String md5(String source){
            //首先判断是否为null或者长度为零
            if (source==null || source.length()==0) {
                return source;
            }

            //1.准备工作
            char [] c = new char[]{'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};
            StringBuilder builder = new StringBuilder();

            //2.获取MessageDigest对象
            MessageDigest digest = null;
            try {
                digest = MessageDigest.getInstance("md5");
            } catch (NoSuchAlgorithmException e) {
                e.printStackTrace();
            }

            //3.获取源字符串的字节数组
            byte[] bytes = source.getBytes();

            //4.执行加密操作
            byte[] target = digest.digest(bytes);

            //5.遍历字节数组
            for (int i = 0; i < target.length; i++) {

                byte b = target[i];

                //6.取高四位和低四位的值
                int high = (b >> 4) & 15;
                int low = b & 15;

                //7.获取对应的字符
                char highChar = c[high];
                char lowChar = c[low];

                //8.拼装字符串
                builder.append(highChar).append(lowChar);

            }

            return builder.toString();

        }
}