java servlet练习测试
步骤：
0、首先创建web project，工程名：test_servlet
1、编写Servlet，TestServlet.java文件内容：
package com.ouyang.servlet;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@SuppressWarnings("serial")
public class TestServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
String url = "jdbc:mysql://localhost:3306/test01";
String user = "root";
String password = "xxx";
Connection connection = null;
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
String sql = "select id, name, age from individual_information";
List<List<String>> record = new ArrayList<>();
try {
Class.forName("com.mysql.jdbc.Driver");
connection = DriverManager.getConnection(url, user, password);
preparedStatement = connection.prepareStatement(sql);
resultSet = preparedStatement.executeQuery();
List<String> tmp = new ArrayList<>();
while (resultSet.next()) {
tmp.add(resultSet.getString("id"));
tmp.add(resultSet.getString("name"));
tmp.add(resultSet.getString("age"));
record.add(new ArrayList<String>(tmp));
tmp.clear();
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
req.setAttribute("individual_information", record);
RequestDispatcher requestDispatcher = req
.getRequestDispatcher("get_info.jsp");
requestDispatcher.forward(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
this.doGet(req, resp);
}
}
2、将servlet添加到web.xml， 添加后的文件内容
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>test_web</display-name>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>testServlet</servlet-name>
<servlet-class>com.ouyang.servlet.TestServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>testServlet</servlet-name>
<url-pattern>/testServlet</url-pattern>
</servlet-mapping>
</web-app>
3、编写跳转页面 get_info.jsp
<%@page import="java.util.List"%>
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>get_info</title>
</head>
<body>
<%
@SuppressWarnings("unchecked")
List<List<String>> record = (List<List<String>>)request.getAttribute("individual_information");
for(List<String> list : record){
out.println("<li>" + list.toString() + "</li>");
}
%>
</body>
</html>
【测试】
访问：http://localhost/test_servlet/testServlet
