Java微信公众号之消息的接收和响应二

刺骨的言语ヽ痛彻心扉 2022-05-25 13:09 150阅读 0赞

## 技术文档 ##

在校验的时候 微信公众平台向我们发送的是Get的请求，而后接收消息的时候，发送的是Post请求，并且消息的发送和接收和发送都是xml格式，现在看看格式：

## 文本消息格式 ##

## 图片消息格式 ##

![这里写图片描述][70]

知道了消息的格式，现在我们要做的就是消息的转化

借助dom4j的jar包，我们可以编写方法，将XML格式，转化对Map对象格式，方法实现如下：

public class MessgaeUtils {
    
           /*将xml格式转化为map*/
            public Map<String,String> xmlToMap(HttpServletRequest request) throws Exception{
               Map<String,String> map=new HashMap<>();
    
                SAXReader reader=new SAXReader();
                InputStream inputStream=request.getInputStream();
                Document doc=reader.read(inputStream);
                Element root=doc.getRootElement();//得到根节点
                List<Element> list=root.elements();//根节点下的所有的节点
                for(Element e:list){
                    map.put(e.getName(),e.getText());
                }
    
                inputStream.close();
                return  map;
            }
    }

消息是实体类：

private String ToUserName;
    
        private String FromUserName;
    
        private Long CreateTime;
    
        private String MsgType;
    
        private String Content;
    
        private String MsgId;

还需要xstream jar将我们的消息内容转变为xml

<dependency>
        <groupId>com.thoughtworks.xstream</groupId>
        <artifactId>xstream</artifactId>
        <version>1.4</version>
    </dependency>

方法：

/*将我们的消息内容转变为xml*/
    
            public static String objectToXml(Message message){
                XStream xStream=new XStream();
                xStream.alias("xml", message.getClass());
                return xStream.toXML(message);
            }

## post方法逻辑： ##

@Override
        protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
            request.setCharacterEncoding("UTF-8");
    
            response.setCharacterEncoding("UTF-8");
    
            PrintWriter out = response.getWriter();
    
            String str = null;
    
    
    
    //将request请求，传到Message工具类的转换方法中，返回接收到的Map对象
               try {
                   Map<String, String> map = MessgaeUtils.xmlToMap(request);
    
    
    
    //从集合中，获取XML各个节点的内容
    
                String ToUserName = map.get("ToUserName");
    
                String FromUserName = map.get("FromUserName");
    
                String CreateTime = map.get("CreateTime");
    
                String MsgType = map.get("MsgType");
    
                String Content = map.get("Content");
    
                String MsgId = map.get("MsgId");
                //这里只处理文本消息
                if (MsgType.equalsIgnoreCase("text")){
    
                    Message message=new Message();
                    message.setFromUserName(ToUserName);
                    message.setToUserName(FromUserName);
                    message.setContent("您发送的消息是text文本消息"+"很帅");
                    message.setMsgId(MsgId);
                    message.setMsgType("text");
                    message.setCreateTime(new Date().getTime());
    
                    str=MessgaeUtils.objectToXml(message);
                }
    
                 System.out.println(str);
    
            }catch (Exception e){
                   e.printStackTrace();
               }
               out.print(str);
               out.close();
        }

结果：  
![这里写图片描述][70 1]

## 对应的url以及token ##

![这里写图片描述][70 2]  
参考：  
[http://www.cnblogs.com/jerehedu/p/6534110.html][http_www.cnblogs.com_jerehedu_p_6534110.html]

## 完整代码 ##

## pom.xml ##

<dependencies>
    
    
        
        <dependency>
          <groupId>dom4j</groupId>
          <artifactId>dom4j</artifactId>
          <version>1.6</version>
        </dependency>
    
        <dependency>
          <groupId>com.thoughtworks.xstream</groupId>
          <artifactId>xstream</artifactId>
          <version>1.4</version>
        </dependency>
    
        <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>4.11</version>
    
        </dependency>
    
        
        <dependency>
          <groupId>jstl</groupId>
          <artifactId>jstl</artifactId>
          <version>1.2</version>
        </dependency>
    
    
        <dependency>
          <groupId>javax.servlet</groupId>
          <artifactId>servlet-api</artifactId>
          <version>2.5</version>
          
        </dependency>
    
      </dependencies>

## servlet ##

public class WeiXinServlet extends HttpServlet {
    
        @Override
        protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
            request.setCharacterEncoding("UTF-8");
    
            response.setCharacterEncoding("UTF-8");
    
            PrintWriter out = response.getWriter();
    
            String str = null;
    
    
    
    //将request请求，传到Message工具类的转换方法中，返回接收到的Map对象
               try {
                   Map<String, String> map = MessgaeUtils.xmlToMap(request);
    
    
    
    //从集合中，获取XML各个节点的内容
    
                String ToUserName = map.get("ToUserName");
    
                String FromUserName = map.get("FromUserName");
    
                String CreateTime = map.get("CreateTime");
    
                String MsgType = map.get("MsgType");
    
                String Content = map.get("Content");
    
                String MsgId = map.get("MsgId");
                //这里只处理文本消息
                if (MsgType.equalsIgnoreCase("text")){
    
                    Message message=new Message();
                    message.setFromUserName(ToUserName);
                    message.setToUserName(FromUserName);
                    message.setContent("您发送的消息是text文本消息"+"很帅");
                    message.setMsgId(MsgId);
                    message.setMsgType("text");
                    message.setCreateTime(new Date().getTime());
    
                    str=MessgaeUtils.objectToXml(message);
                }
    
                 System.out.println(str);
    
            }catch (Exception e){
                   e.printStackTrace();
               }
               out.print(str);
               out.close();
        }
    
         @Override
        protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{
    
            System.out.println(request.getMethod().toString());
            while (request.getAttributeNames().hasMoreElements()){
                System.out.println("1");
                request.getAttributeNames().nextElement();
            }
            // 微信加密签名
            String signature = request.getParameter("signature");
    
            // 时间戳
            String timestamp = request.getParameter("timestamp");
    
            // 随机数
            String nonce = request.getParameter("nonce");
    
    
            // 随机字符串  由于我使用的是申请的测试账号，并没有随机字符串随意这里的ech是null
            String ech = request.getParameter("echostr");
    
            PrintWriter out = response.getWriter();
    
            if (CheckUtil.checkSignature(signature,timestamp,nonce))
                 System.out.println("校验成功");
    
                  out.print(ech);
    
               }
    
        }

## web.xml ##

<?xml version="1.0" encoding="UTF-8"?>
    
    <web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
    
    
         <servlet>
           <servlet-name>bb</servlet-name>
           <servlet-class>yiche.com.servlet.WeiXinServlet</servlet-class>
         </servlet>
        <servlet-mapping>
          <servlet-name>bb</servlet-name>
          <url-pattern>/ok.do</url-pattern>
        </servlet-mapping>
    </web-app>

## 文本消息 ##

public class Message {
    
    
        private String ToUserName;
    
        private String FromUserName;
    
        private Long CreateTime;
    
        private String MsgType;
    
        private String Content;
    
        private String MsgId;

## 消息转化工具类 ##

public class MessgaeUtils {
    
    
           /*将xml格式转化为map*/
            public static Map<String,String> xmlToMap(HttpServletRequest request) throws Exception{
               Map<String,String> map=new HashMap<>();
    
                SAXReader reader=new SAXReader();
                InputStream inputStream=request.getInputStream();
                Document doc=reader.read(inputStream);
                Element root=doc.getRootElement();//得到根节点
                List<Element> list=root.elements();//根节点下的所有的节点
                for(Element e:list){
                    map.put(e.getName(),e.getText());
                }
    
                inputStream.close();
                return  map;
            }
    
            /*将我们的消息内容转变为xml*/
    
            public static String objectToXml(Message message){
                XStream xStream=new XStream();
                xStream.alias("xml", message.getClass());
                return xStream.toXML(message);
            }
    }

## doGet方法校验以及加密工具类 ##

public class CheckUtil { 
    
        public static final String tooken = "jkjkjkhk"; //开发者自行定义Tooken
    
    
        //signatrue微信公众平台传过来的的经过加密的签名
        public static boolean checkSignature(String signature, String timestamp, String nonce) {
    
    //1.定义数组存放tooken，timestamp,nonce
    
            String[] arr = {tooken, timestamp, nonce};
    
    //2.对数组进行排序
    
            Arrays.sort(arr);
    
    //3.生成字符串
    
            StringBuffer sb = new StringBuffer();
    
            for (String s : arr) {
    
                sb.append(s);
    
            }
    
    //4.sha1加密,网上均有现成代码
    
            String temp = getSha1(sb.toString());
    
    //5.将加密后的字符串，与微信传来的加密签名比较，返回结果
    
            return temp.equals(signature);
        }
    
    
    
        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("UTF-8"));
    
    
    
                byte[] md = mdTemp.digest();
    
                int j = md.length;
    
                char buf[] = new char[j*2];
    
                int k = 0;
    
                for (int i = 0; i < j; i++) {
    
                    byte byte0 = md[i];
    
                    buf[k++] = hexDigits[byte0 >>> 4 & 0xf];
    
                    buf[k++] = hexDigits[byte0 & 0xf];
    
                }
    
                return new String(buf);
    
            } catch (Exception e) {
    
                // TODO: handle exception
    
                return null;
    
            }
    
        }
    
    
    }

[70]: /images/20220525/8ab2a391253644e281b480b332a6d4c2.png
[70 1]: /images/20220525/d96a55c2ae7b4a43b14e01c52996dbb5.png
[70 2]: /images/20220525/f2b536b9ac2f49319ce65de06db79994.png
[http_www.cnblogs.com_jerehedu_p_6534110.html]: http://www.cnblogs.com/jerehedu/p/6534110.html