package com.chuanghai.ihotel.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * 门锁md5工具
 */
public class DoorLockMD5Util {

    /**
     * MD5加密
     *
     * @param str  明文
     * @return 密文
     * @throws Exception
     */
    public static String getMD5(String str) {
        char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
        try {
            byte[] strTemp = str.getBytes();
            // 使用MD5创建MessageDigest对象
            MessageDigest mdTemp = MessageDigest.getInstance("MD5");
            mdTemp.update(strTemp);
            byte[] md = mdTemp.digest();
            int j = md.length;
            char ch[] = new char[j * 2];
            int k = 0;
            for (int i = 0; i < j; i++) {
                byte b = md[i];
                // 将每个数(int)b进行双字节加密s
                ch[k++] = hexDigits[b >> 4 & 0xf];
                ch[k++] = hexDigits[b & 0xf];
            }
            return new String(ch);
        } catch (NoSuchAlgorithmException e) {
            return null;
        }
    }
}