java - kendo ui grid 未从 servlet 接收 json 数据

Question

我有一个名为 javaservlet 的 netbeans Web 应用程序。这个项目包有一个 servlet databaseconnection.java。这里我从数据库表 employee 中检索了 6 行，该表有 3 列 eid,ename,esalary 并将其显示为 json 值 在“http://localhost:8084/javaservlet/databaseconnection”url中。现在我想显示kendo网格中的所有6行数据。在WEB-INF文件夹中的index.html页面中，我尝试从url中读取json数据。但它不起作用。我在 kendo ui 网格中添加了三个标题 EmployeeSalary,EmployeeName,EmployeeId 和三个字符串字段。当我运行文件时，仅在数据库表只有一行但表有多于一行时显示值 kendo没有显示任何数据..为什么会发生这种情况。请帮助我解决问题。这是我的代码数据库连接.java

import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
 import java.sql.Statement;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.json.*;

@WebServlet(urlPatterns = {"/databaseconnection"})
public class databaseconnection extends HttpServlet {

protected void processRequest(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {
    response.setContentType("application/json");
    PrintWriter out = response.getWriter();
    Connection connection = null;
    Statement stmt = null;
    JSONArray jArray = new JSONArray();
    JSONObject jobj = new JSONObject();
    try {
        Class.forName("org.postgresql.Driver");
        connection = DriverManager.getConnection("jdbc:postgresql://localhost:5432/test", "postgres", "root");
        stmt = connection.createStatement();
     //  String sql = "INSERT INTO employee (eid,ename,esalary) " + "VALUES (7, 'Nadia', 35000)";
        //  stmt.executeUpdate(sql);
        ResultSet result = stmt.executeQuery("Select eid,ename,esalary from employee");
        while (result.next()) {
            String eid = result.getString("eid");
            String ename = result.getString("ename");
            String esalary = result.getString("esalary");
            jobj.put("eid", eid);
            jobj.put("ename", ename);
            jobj.put("esalary", esalary);
            out.print(jobj);
            out.flush();    

           // jArray.put(jobj);
            // System.out.print(jobj);
        }

    } catch (SQLException e) {

        System.out.println("Connection Failed! Check output console");
        e.printStackTrace();
        return;

    } catch (ClassNotFoundException ex) {
        Logger.getLogger(databaseconnection.class.getName()).log(Level.SEVERE, null, ex);
    }


}

Answer 1

请将 jsonobject 添加到 while Loop.ex 内的 jsonarray 中:

 while (result.next()) {
            String type_json = result.getString("eid");
            String name_json = result.getString("ename");
            String id_json = result.getString("esalary");
            jobj.put("eid", type_json);
            jobj.put("ename", name_json);
            jobj.put("esalary", id_json);
            **jArray.add(jobj);**

        }