改bug

src/com/hellogithub/dao/UserDao.java

@@ -170,4 +170,22 @@ public class UserDao {
 
         return num;
     }
+
+    /*
+     *
+     * 返回用户总数
+     * */
+    public int  queryUserCount(){
+        int num;
+        try {
+            Connection conn = JdbcUtils.getConnection();
+            QueryRunner runner = new QueryRunner();
+            String sql="select count(*) from user";
+            num = runner.query(conn,sql,new BeanHandler<>(Integer.class));
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+
+        return num;
+    }
 }

src/com/hellogithub/dao/projectDao.java

@@ -131,8 +131,8 @@ public class projectDao {
         try {
             Connection conn = JdbcUtils.getConnection();
             QueryRunner runner = new QueryRunner();
-            String sql = "select * from project order by lookCount desc";
-            projectEntityList = runner.query(conn, sql, new BeanListHandler<>(projectEntity.class));
+            String sql = "select * from project where categoryId = ? order by lookCount desc";
+            projectEntityList = runner.query(conn, sql, new BeanListHandler<>(projectEntity.class),id);
             conn.close();
         } catch (SQLException e) {
             throw new RuntimeException(e);

src/com/hellogithub/service/UserService.java

@@ -47,4 +47,5 @@ public class UserService {
      * @param name
      * */
     public int  dedleteAllLabel(String name){return userDao.dedleteAllLabel(name);}
+    public int queryUserCount(){return userDao.queryUserCount();}
 }

src/com/hellogithub/servlet/userNumServlet.java

@@ -0,0 +1,70 @@
+package com.hellogithub.servlet;
+
+import com.alibaba.fastjson.JSONObject;
+import com.hellogithub.service.UserService;
+import jakarta.servlet.ServletConfig;
+import jakarta.servlet.ServletException;
+import jakarta.servlet.http.HttpServlet;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.util.HashMap;
+
+public class userNumServlet extends HttpServlet {
+    private UserService userService = new UserService();
+    @Override
+    public void init(ServletConfig config) throws ServletException {
+
+    }
+
+    @Override
+    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        doPost(req, resp);
+    }
+
+    @Override
+    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        resp.setCharacterEncoding("UTF-8");
+        resp.setContentType("text/html; charset=utf-8");
+        //        设置响应头允许ajax跨域访问
+        String curOrigin = req.getHeader("Origin");
+        resp.setHeader("Access-Control-Allow-Origin", curOrigin == null ? "true" : curOrigin);
+        resp.setHeader("Access-Control-Allow-Credentials", "true");
+        resp.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE, HEAD");
+        resp.setHeader("Access-Control-Max-Age", "3600");
+        resp.setHeader("Access-Control-Allow-Headers", "access-control-allow-origin, authority, content-type, version-info, X-Requested-With");
+        resp.setContentType("application/json;charset=UTF-8");
+
+        PrintWriter writer = resp.getWriter();
+        int num = userService.queryUserCount();
+        String  str= "num:"+num ;
+        String jsonString = JSONObject.toJSONString(str);
+        writer.println(jsonString);
+        if(num == 0)
+        {
+            setResultError("用户总数为空",writer);
+        }else{
+            setResultOK("success",writer);
+        }
+
+        writer.close();
+    }
+    public void setResult(Integer code, String msg, PrintWriter writer) {
+        HashMap<String, Object> result = new HashMap<>();
+        result.put("code", code);
+        result.put("msg", msg);
+        String jsonString = JSONObject.toJSONString(result);
+        writer.println(jsonString);
+        writer.close();
+    }
+
+    public void setResultError(String msg, PrintWriter writer) {
+        setResult(500, msg, writer);
+    }
+
+    public void setResultOK(String msg, PrintWriter writer) {
+        setResult(200, msg, writer);
+    }
+}