JAVA-EE的动态展示数据库中的信息------计算机网络经典

朴灿烈づ我的快乐病毒、 2024-03-02 02:27 39阅读 0赞

>     <!DOCTYPE html>
>     <html lang="en">
>     <head>
>         <meta charset="UTF-8">
>         <title>Title</title>
>     </head>
>     <body>
>         <a href="/servlet/student">studentList</a>
>     </body>
>     </html>
> 
>     <!DOCTYPE html>
>     <html lang="en">
>     <head>
>         <meta charset="UTF-8">
>         <title>Title</title>
>     </head>
>     <body>
>         <a href="/servlet/student">studentList</a>
>     </body>
>     </html>

>     <?xml version="1.0" encoding="UTF-8"?>
>     <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
>              xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
>              xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
>              version="4.0">
>         <servlet>
>             <servlet-name>studentServlet</servlet-name>
>             <servlet-class>com.bjpowernode.javaweb.servlet.StudentServlet</servlet-class>
>         </servlet>
>         <servlet-mapping>
>             <servlet-name>studentServlet</servlet-name>
>             <url-pattern>/servlet/student</url-pattern>
>         </servlet-mapping>
>     </web-app>
> 
>     <?xml version="1.0" encoding="UTF-8"?>
>     <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
>              xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
>              xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
>              version="4.0">
>         <servlet>
>             <servlet-name>studentServlet</servlet-name>
>             <servlet-class>com.bjpowernode.javaweb.servlet.StudentServlet</servlet-class>
>         </servlet>
>         <servlet-mapping>
>             <servlet-name>studentServlet</servlet-name>
>             <url-pattern>/servlet/student</url-pattern>
>         </servlet-mapping>
>     </web-app>

>     package com.bjpowernode.javaweb.servlet;
>     
>     import jakarta.servlet.*;
>     
>     import java.io.IOException;
>     import java.io.PrintWriter;
>     import java.sql.*;
>     
>     public class StudentServlet implements Servlet
>     {
>         @Override
>         public void init(ServletConfig servletConfig) throws ServletException {
>     
>         }
>     
>         @Override
>         public ServletConfig getServletConfig() {
>             return null;
>         }
>     
>         @Override
>         public void service(ServletRequest servletRequest, ServletResponse servletResponse) throws ServletException, IOException {
>             Connection connection = null;
>             PreparedStatement ps = null;
>             ResultSet set = null;
>             servletResponse.setContentType("text/html");
>             PrintWriter writer = servletResponse.getWriter();
>             try
>             {
>                 Class.forName("com.mysql.cj.jdbc.Driver");
>                 String url = "jdbc:mysql://127.0.0.1:13306/powernode";
>                 String user = "root";
>                 String password = "abc123";
>                 connection = DriverManager.getConnection(url,user,password);
>                 String sql = "select id,name from t_student";
>                 ps = connection.prepareStatement(sql);
>                 set = ps.executeQuery();
>                 while (set.next())
>                 {
>                     String id = set.getString("id");
>                     String name = set.getString("name");
>                     writer.println(id + "," + name);
>                 }
>             }
>             catch(Exception e)
>             {
>                 e.printStackTrace();
>             }
>             finally {
>                 if (connection != null) {
>                     try {
>                         connection.close();
>                     } catch (SQLException e) {
>                         throw new RuntimeException(e);
>                     }
>                 }
>                 if (set != null) {
>                     try {
>                         set.close();
>                     } catch (SQLException e) {
>                         throw new RuntimeException(e);
>                     }
>                 }
>                 if (ps != null) {
>                     try {
>                         ps.close();
>                     } catch (SQLException e) {
>                         throw new RuntimeException(e);
>                     }
>                 }
>             }
>         }
>     
>         @Override
>         public String getServletInfo() {
>             return null;
>         }
>     
>         @Override
>         public void destroy() {
>     
>         }
>     }
> 
>     package com.bjpowernode.javaweb.servlet;
>     
>     import jakarta.servlet.*;
>     
>     import java.io.IOException;
>     import java.io.PrintWriter;
>     import java.sql.*;
>     
>     public class StudentServlet implements Servlet
>     {
>         @Override
>         public void init(ServletConfig servletConfig) throws ServletException {
>     
>         }
>     
>         @Override
>         public ServletConfig getServletConfig() {
>             return null;
>         }
>     
>         @Override
>         public void service(ServletRequest servletRequest, ServletResponse servletResponse) throws ServletException, IOException {
>             Connection connection = null;
>             PreparedStatement ps = null;
>             ResultSet set = null;
>             servletResponse.setContentType("text/html");
>             PrintWriter writer = servletResponse.getWriter();
>             try
>             {
>                 Class.forName("com.mysql.cj.jdbc.Driver");
>                 String url = "jdbc:mysql://127.0.0.1:13306/powernode";
>                 String user = "root";
>                 String password = "abc123";
>                 connection = DriverManager.getConnection(url,user,password);
>                 String sql = "select id,name from t_student";
>                 ps = connection.prepareStatement(sql);
>                 set = ps.executeQuery();
>                 while (set.next())
>                 {
>                     String id = set.getString("id");
>                     String name = set.getString("name");
>                     writer.println(id + "," + name);
>                 }
>             }
>             catch(Exception e)
>             {
>                 e.printStackTrace();
>             }
>             finally {
>                 if (connection != null) {
>                     try {
>                         connection.close();
>                     } catch (SQLException e) {
>                         throw new RuntimeException(e);
>                     }
>                 }
>                 if (set != null) {
>                     try {
>                         set.close();
>                     } catch (SQLException e) {
>                         throw new RuntimeException(e);
>                     }
>                 }
>                 if (ps != null) {
>                     try {
>                         ps.close();
>                     } catch (SQLException e) {
>                         throw new RuntimeException(e);
>                     }
>                 }
>             }
>         }
>     
>         @Override
>         public String getServletInfo() {
>             return null;
>         }
>     
>         @Override
>         public void destroy() {
>     
>         }
>     }