通过java实现微信公众号发送微信消息

（感谢好多老哥提供的文档，哈哈，这里我就只是代码贴出来，方便以后copy）

1获取token

String token = Wechat.getAccess_token(appId, appSecret).getString("access_token");

    public static JSONObject getAccess_token(String appId, String appSecret) {
        String url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=" + appId + "&secret=" + appSecret;
        String accessToken = null;
        JSONObject jsonObj = null;
        try {
            URL urlGet = new URL(url);
            HttpURLConnection http = (HttpURLConnection) urlGet.openConnection();
            http.setRequestMethod("GET"); // 必须是get方式请求
            http.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
            http.setDoOutput(true);
            http.setDoInput(true);
            http.connect();
            InputStream is = http.getInputStream();
            int size = is.available();
            byte[] jsonBytes = new byte[size];
            is.read(jsonBytes);
            accessToken = new String(jsonBytes, "UTF-8");
            System.err.println(accessToken);
            jsonObj = JSONObject.parseObject(accessToken);
            is.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return jsonObj;
    }

2调用service层发消息模板

TemplateMessageService.sendTemp(appId, token, appSecret, entity.realAmount, tenantEntity.name, memberEntity.wechatOpenId);

3进入该模板后会调用httputil类，发送消息

package com.mall.common.services;


import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.mall.common.utils.HttpSend;
import com.mall.common.utils.HttpUtil;

import java.io.UnsupportedEncodingException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;

public class TemplateMessageService {

    public static void sendTemp(String appid, String accessToken, String appSecret, Double realAmount, String shopName, String openId) {
        String url = "https://api.weixin.qq.com/cgi-bin/token";
        String param = "grant_type=client_credential" + "&appid=" + appid + "&secret=" + appSecret;
        String accTemp = HttpSend.sendGet(url, param);
        JSONObject jsonObject = JSONObject.parseObject(accTemp);
        System.out.println("1--->" + jsonObject);
        accessToken = jsonObject.getString("access_token"); // 获取到了access_token，调用接口都要用到的，有时效
        // 封装要发送的json
        Map<String, Object> map = new HashMap();
        map.put("touser", openId);//你要发送给某个用户的openid 前提是已关注该公众号,该openid是对应该公众号的，不是普通的openid
        map.put("template_id", "VkxwzizOa2YS_M2RQbVQHPHzHTbabAqLvqU5FNFqQVs");//模板消息id
        //map.put("url","https://www.vipkes.cn");//用户点击模板消息，要跳转的地址
        // 封装miniprogram 跳转小程序用,不跳不要填
        Map<String, String> mapA = new HashMap<>();
        mapA.put("appid", ""); //小程序appid
        mapA.put("pagepath", ""); //小程序页面pagepath
        map.put("miniprogram", mapA);

        // 以下就是根据模板消息的格式封装好，我模板的是：问题反馈结果通知  可以和我一样试试
        // 封装first
        Map firstMap = new HashMap();
        firstMap.put("value", "新的消费通知！"); //内容
        firstMap.put("color", "#173177"); //字体颜色

        // 封装keyword1 提交的问题
        Map keyword1Map = new HashMap();
        keyword1Map.put("value", shopName);
        keyword1Map.put("color", "#fff");

        // 封装keyword2此处也可以是商品名
        Map keyword2Map = new HashMap();
        keyword2Map.put("value", "-");
        keyword2Map.put("color", "#fff");

        // 封装keyword2此处可以是商品价格
        Map keyword3Map = new HashMap();
        keyword3Map.put("value", realAmount + "元");
        keyword3Map.put("color", "#fff");

        // 封装keyword4
        // 封装remark
        Date date = new Date();
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Map keyword4Map = new HashMap();
        keyword4Map.put("value", simpleDateFormat.format(date));
        keyword4Map.put("color", "#fff");


        Map remarkMap = new HashMap();
        remarkMap.put("value", "尊敬的用户,您于" + simpleDateFormat.format(date) + "在" + shopName + "消费了" + realAmount + "元");
        remarkMap.put("color", "#fff");

        // 封装data
        Map dataMap = new HashMap();
        dataMap.put("first", firstMap);
        dataMap.put("keyword1", keyword1Map);
        dataMap.put("keyword2", keyword2Map);
        dataMap.put("keyword3", keyword3Map);
        dataMap.put("keyword4", keyword4Map);
        dataMap.put("remark", remarkMap);

        map.put("data", dataMap);
        String r = HttpUtil.getJsonData(JSONObject.parseObject(JSON.toJSONString(map)), "https://api.weixin.qq.com/cgi-bin/message/template/send?access_token=" + accessToken); //发送模板消息，这里有个工具类，我给你哟
        System.out.println("-->" + r);
    }


    public static void sendTempPoint(String appid, String accessToken, String appSecret, Integer Id, String name, String mobile, Double amount, String wechatOpenId) {
        String url = "https://api.weixin.qq.com/cgi-bin/token";
        String param = "grant_type=client_credential" + "&appid=" + appid + "&secret=" + appSecret;
        String accTemp = HttpSend.sendGet(url, param);
        JSONObject jsonObject = JSONObject.parseObject(accTemp);
        System.out.println("1--->" + jsonObject);
        accessToken = jsonObject.getString("access_token"); // 获取到了access_token，调用接口都要用到的，有时效
        // 封装要发送的json
        Map<String, Object> map = new HashMap();
        map.put("touser", wechatOpenId);//你要发送给某个用户的openid 前提是已关注该公众号,该openid是对应该公众号的，不是普通的openid
        map.put("template_id", "672dPs0Jwl9zLvhVrncI0nyEHxX3Mx-fPNLBcIEb05A");//模板消息id
        //map.put("url","https://www.vipkes.cn");//用户点击模板消息，要跳转的地址
        // 封装miniprogram 跳转小程序用,不跳不要填
        Map<String, String> mapA = new HashMap<>();
        mapA.put("appid", ""); //小程序appid
        mapA.put("pagepath", ""); //小程序页面pagepath
        map.put("miniprogram", mapA);

        // 以下就是根据模板消息的格式封装好，我模板的是：问题反馈结果通知  可以和我一样试试
        // 封装first
        Map firstMap = new HashMap();
        firstMap.put("value", "会员积分消费提醒！"); //内容
        firstMap.put("color", "#173177"); //字体颜色
        String newname;
        try {
            newname = (java.net.URLDecoder.decode(name, "UTF-8"));
        } catch (UnsupportedEncodingException e) {
            newname = name;
        }

        // 封装keyword1 提交的问题
        Map XM = new HashMap();
        XM.put("value", newname);
        XM.put("color", "#fff");

        // 封装keyword2此处也可以是商品名
        Map KH = new HashMap();
        KH.put("value", Id);
        KH.put("color", "#fff");
        Date date = new Date();
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        // 封装keyword3此处可以是商品价格
        Map CONTENTS = new HashMap();
        CONTENTS.put("value", "尊敬的用户,您的账户于" + simpleDateFormat.format(date) + "增加了" + amount + "积分");
        CONTENTS.put("color", "#fff");


        Map remarkMap = new HashMap();
        remarkMap.put("value", "消息惠顾");
        remarkMap.put("color", "#fff");

        // 封装data
        Map dataMap = new HashMap();
        dataMap.put("first", firstMap);
        dataMap.put("XM", XM);
        dataMap.put("KH", KH);
        dataMap.put("CONTENTS", CONTENTS);
        dataMap.put("remark", remarkMap);

        map.put("data", dataMap);
        String r = HttpUtil.getJsonData(JSONObject.parseObject(JSON.toJSONString(map)), "https://api.weixin.qq.com/cgi-bin/message/template/send?access_token=" + accessToken); //发送模板消息，这里有个工具类，我给你哟
        System.out.println("-->" + r);
    }


}

4发送消息

package com.mall.common.utils;


import com.alibaba.fastjson.JSONObject;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.URL;

public class HttpUtil {

    public static String getJsonData(JSONObject jsonParam, String urls) {
        StringBuffer sb = new StringBuffer();
        try {
            // 创建url资源
            URL url = new URL(urls);
            // 建立http连接
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            // 设置允许输出
            conn.setDoOutput(true);
            // 设置允许输入
            conn.setDoInput(true);
            // 设置不用缓存
            conn.setUseCaches(false);
            // 设置传递方式
            conn.setRequestMethod("POST");
            // 设置维持长连接
            conn.setRequestProperty("Connection", "Keep-Alive");
            // 设置文件字符集:
            conn.setRequestProperty("Charset", "UTF-8");
            // 转换为字节数组
            byte[] data = (jsonParam.toString()).getBytes();
            // 设置文件长度
            conn.setRequestProperty("Content-Length", String.valueOf(data.length));
            // 设置文件类型:
            conn.setRequestProperty("contentType", "application/json");
            // 开始连接请求
            conn.connect();
            //OutputStream out = new DataOutputStream(conn.getOutputStream()) ;
            //防止消息乱码
            OutputStreamWriter out = new OutputStreamWriter(conn.getOutputStream(), "utf-8");
            // 写入请求的字符串
            out.write(jsonParam.toString());
            out.flush();
            out.close();

            System.out.println(conn.getResponseCode());

            // 请求返回的状态
            if (HttpURLConnection.HTTP_OK == conn.getResponseCode()) {
                System.out.println("连接成功");
                // 请求返回的数据
                InputStream in1 = conn.getInputStream();
                try {
                    String readLine = new String();

                    BufferedReader responseReader = new BufferedReader(new InputStreamReader(in1, "UTF-8"));
                    while ((readLine = responseReader.readLine()) != null) {
                        sb.append(readLine).append("\n");
                    }
                    responseReader.close();
                    System.out.println(sb.toString());

                } catch (Exception e1) {
                    e1.printStackTrace();
                }
            } else {
                System.out.println("error++");

            }

        } catch (Exception e) {

        }

        return sb.toString();

    }

    /**
     * @auther: cxl
     * @Description 发送post请求  参数String
     * @date: 2019/4/28 19:38
     */
    public static String post(String jsonParam, String urls) {
        StringBuffer sb = new StringBuffer();
        try {
            // 创建url资源
            URL url = new URL(urls);
            // 建立http连接
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            // 设置允许输出
            conn.setDoOutput(true);
            // 设置允许输入
            conn.setDoInput(true);
            // 设置不用缓存
            conn.setUseCaches(false);
            // 设置传递方式
            conn.setRequestMethod("POST");
            // 设置维持长连接
            conn.setRequestProperty("Connection", "Keep-Alive");
            // 设置文件字符集:
            conn.setRequestProperty("Charset", "UTF-8");
            // 转换为字节数组
            //byte[] data = (jsonParam.toString()).getBytes();
            // 设置文件长度
            // conn.setRequestProperty("Content-Length", String.valueOf(data.length));
            // 设置文件类型:
            conn.setRequestProperty("contentType", "application/text");
            // 开始连接请求
            conn.connect();
            //防止消息乱码
            OutputStreamWriter out = new OutputStreamWriter(conn.getOutputStream(), "utf-8");
            // 写入请求的字符串
            out.write(jsonParam.toString());
            out.flush();
            out.close();
            System.out.println(conn.getResponseCode());
            // 请求返回的状态
            if (HttpURLConnection.HTTP_OK == conn.getResponseCode()) {
                System.out.println("连接成功");
                // 请求返回的数据
                InputStream in1 = conn.getInputStream();
                try {
                    String readLine = new String();
                    BufferedReader responseReader = new BufferedReader(new InputStreamReader(in1, "UTF-8"));
                    while ((readLine = responseReader.readLine()) != null) {
                        sb.append(readLine).append("\n");
                    }
                    responseReader.close();
                    System.out.println(sb.toString());
                } catch (Exception e1) {
                    e1.printStackTrace();
                }
            } else {
                System.out.println("error++");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return sb.toString();
    }

}

5以下问题是之后出的问题

此处如果不写utf-8本地postman测试不一定会乱码 ，上传线上有几率乱码，我遇到了，被骂死，哈哈，其他的真没什么问题，openid是他们提供的，我不太清楚，然后千万别乱给微信公众号，他们给错公众号害得我一直显示未关注公众号，擦，说了他们不信