6. 相关工具类(生成签名,验签,发起 POST 请求)

package com.cheeli.*;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONException;
import com.alibaba.fastjson.JSONObject;
import com.cheeli.earthmother.web.dto.api.FranchiserResult;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

import java.io.*;
import java.net.URLDecoder;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Map;

public class CheeliUtils {

    public static String getJsonStrByQueryUrl(String paramStr) throws UnsupportedEncodingException {
        paramStr = URLDecoder.decode(paramStr, "UTF-8");
        String[] params = paramStr.split("&");
        JSONObject obj = new JSONObject();
        for (int i = 0; i < params.length; i++) {
            String[] param = params[i].split("=");
            if (param.length >= 2) {
                String key = param[0];
                String value = param[1];
                for (int j = 2; j < param.length; j++) {
                    value += "=" + param[j];
                }
                try {
                    obj.put(key,value);
                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        }
        return obj.toString();
    }


    //参数签名
    public static String Sign(Map<String, String> params,String appSecret) throws NoSuchAlgorithmException, UnsupportedEncodingException
    {
        String[] keys = params.keySet().toArray(new String[0]);
        Arrays.sort(keys);

        StringBuilder query = new StringBuilder();
        query.append(appSecret);
        for (String key : keys) {
            String value = params.get(key);
            query.append(key).append(value);
        }
        query.append(appSecret);
        byte[] md5byte = encryptMD5(query.toString());
        return  byte2hex(md5byte);
    }
    //byte数组转成16进制字符串
    public static String byte2hex(byte[] bytes) {
        StringBuilder sign = new StringBuilder();
        for (int i = 0; i < bytes.length; i++) {
            String hex = Integer.toHexString(bytes[i] & 0xFF);
            if (hex.length() == 1) {
                sign.append("0");
            }
            sign.append(hex.toLowerCase());
        }
        return sign.toString();
    }
    //Md5摘要
    public static byte[] encryptMD5(String data) throws NoSuchAlgorithmException, UnsupportedEncodingException {
        MessageDigest md5 = MessageDigest.getInstance("MD5");
        return md5.digest(data.getBytes("UTF-8"));
    }

    public static String doHttpRequest(String url, Map<String, String> data) {
        String result = "";
        CloseableHttpClient httpclient = HttpClients.createDefault();
        HttpPost httpPost = new HttpPost(url);
        System.out.println("请求Url:" + url);
        System.out.println("请求数据:" + JSON.toJSONString(data));
        List<BasicNameValuePair> params = new ArrayList<BasicNameValuePair>();
        for (Map.Entry<String, String> entry : data.entrySet()) {
            params.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
        }
        //发起POST请求
        try {
            httpPost.setEntity(new UrlEncodedFormEntity(params, "UTF-8"));
            HttpResponse httpResponse = httpclient.execute(httpPost);
            if (httpResponse.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                result = EntityUtils.toString(httpResponse.getEntity());
            } else {
                result = ("doPost Error Response: " + httpResponse.getStatusLine().toString());
            }
        } catch (Exception e) {
            result = JSON.toJSONString(new FranchiserResult<>(-1,e.getMessage(),null));
            e.printStackTrace();
        }

        return result;
    }

}