package com.gree.mall.contest.utils;

import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;

public class ShaUtils {

    public static String getSha1(String str){
        if(str==null||str.length()==0){
            return null;
        }
        char[] hexDigits = {'0','1','2','3','4','5','6','7','8','9',
                'a','b','c','d','e','f'};
        try {
            MessageDigest mdTemp = MessageDigest.getInstance("SHA1");
            mdTemp.update(str.getBytes(StandardCharsets.UTF_8));

            byte[] md = mdTemp.digest();
            int j = md.length;
            char[] buf = new char[j*2];
            int k = 0;
            for (byte byte0 : md) {
                buf[k++] = hexDigits[byte0 >>> 4 & 0xf];
                buf[k++] = hexDigits[byte0 & 0xf];
            }
            return new String(buf);
        } catch (Exception e) {
            return null;
        }
    }


}