package com.jiayue.client.util;

import java.security.MessageDigest;

/**
 * MD5 工具类-建议添油加醋的对入参 str 改造一下
 *
 * @author Administrator
 */
public class MD5Util {


    //工具类不允许被实例化
    private MD5Util() throws Exception {
        throw new Exception("异常");
    }

    public static String encode(String str) {
        MessageDigest md5;
        try {
            md5 = MessageDigest.getInstance("MD5");
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        char[] charArray = str.toCharArray();
        byte[] byteArray = new byte[charArray.length];

        for (int i = 0; i < charArray.length; i++) {
            byteArray[i] = (byte) charArray[i];
        }

        byte[] md5Bytes = md5.digest(byteArray);
        StringBuilder hexValue = new StringBuilder();
        for (byte md5Byte : md5Bytes) {
            int val = ((int) md5Byte) & 0xff;
            if (val < 16) {
                hexValue.append("0");
            }

            hexValue.append(Integer.toHexString(val));
        }
        return hexValue.toString();
    }

    /**
     * 字符串的MD5
     *
     * @param plainText  内容
     * @param encryption 加密
     * @return 加密结果
     */
    public static String encode(String plainText, String encryption) {
        try {
            MessageDigest md = MessageDigest.getInstance(encryption);
            md.update(plainText.getBytes());
            byte[] b = md.digest();

            int i;

            StringBuilder buf = new StringBuilder();
            for (byte value : b) {
                i = value;
                if (i < 0)
                    i += 256;
                if (i < 16)
                    buf.append("0");
                buf.append(Integer.toHexString(i));
            }
            return buf.toString();

        } catch (Exception e) {
            e.printStackTrace();
        }
        return "";
    }
}