一、基本环境准备
1、配置pop.xml
pop文件可以直接复制使用不作修改，也可以根据自己的需求进行增删依赖和插件
1 <?xml version="1.0" encoding="UTF-8"?> 2 <project xmlns="http://maven.apache.org/POM/4.0.0" 3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 4 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> 5 <modelVersion>4.0.0</modelVersion> 6 7 <groupId>org.tree</groupId> 8 <artifactId>A-lin</artifactId> 9 <version>1.0-SNAPSHOT</version> 10 <packaging>war</packaging> 11 12 <properties> 13 <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> 14 <maven.compiler.source>17</maven.compiler.source> 15 <maven.compiler.target>17</maven.compiler.target> 16 </properties> 17 18 19 <dependencies> 20 <!--mybatis--> 21 <dependency> 22 <groupId>org.mybatis</groupId> 23 <artifactId>mybatis</artifactId> 24 <version>3.5.11</version> 25 </dependency> 26 <!--mySql--> 27 <dependency> 28 <groupId>mysql</groupId> 29 <artifactId>mysql-connector-java</artifactId> 30 <version>8.0.30</version> 31 </dependency> 32 <!--servlet--> 33 <dependency> 34 <groupId>javax.servlet</groupId> 35 <artifactId>javax.servlet-api</artifactId> 36 <version>3.1.0</version> 37 <scope>provided</scope> 38 </dependency> 39 <!--jsp--> 40 <dependency> 41 <groupId>javax.servlet.jsp</groupId> 42 <artifactId>jsp-api</artifactId> 43 <version>2.2</version> 44 <scope>provided</scope> 45 </dependency> 46 <!--jstl--> 47 <dependency> 48 <groupId>jstl</groupId> 49 <artifactId>jstl</artifactId> 50 <version>1.2</version> 51 </dependency> 52 53 <dependency> 54 <groupId>taglibs</groupId> 55 <artifactId>standard</artifactId> 56 <version>1.1.2</version> 57 </dependency> 58 59 <dependency> 60 <groupId>com.alibaba</groupId> 61 <artifactId>fastjson</artifactId> 62 <version>1.2.62</version> 63 </dependency> 64 65 </dependencies> 66 67 <build> 68 <plugins> 69 <plugin> 70 <groupId>org.apache.tomcat.maven</groupId> 71 <artifactId>tomcat7-maven-plugin</artifactId> 72 <version>2.2</version> 73 </plugin> 74 </plugins> 75 </build> 76 77 </project>
2、配置mybatis.xml
mybatis文件要修改为自己的包名和数据库配置(database,username,password)
1 <?xml version="1.0" encoding="UTF-8" ?> 2 <!DOCTYPE configuration 3 PUBLIC "-//mybatis.org//DTD Config 3.0//EN" 4 "http://mybatis.org/dtd/mybatis-3-config.dtd"> 5 <configuration> 8 <!-- 1.改包名 9 2.数据库配置，数据库名称，用户名，密码 10 --> 12 <!--起别名--> 13 <typeAliases> <!--改包名--> 14 <package name="com.tree.entity"/> 15 </typeAliases> 16 17 <environments default="development"> 18 <environment id="development"> 19 <transactionManager type="JDBC"/> 20 <dataSource type="POOLED"> 21 <property name="driver" value="com.mysql.cj.jdbc.Driver"/> 22 <property name="url" value="jdbc:mysql:///tree?useSSL=false&useServerPrepStmts=true"/> 23 <property name="username" value="root"/> 24 <property name="password" value="root"/> 25 </dataSource> 26 </environment> 27 </environments> 28 <mappers> 29 <!--扫描mapper--> 30 <package name="com.tree.mapper"/><!--改包名--> 31 </mappers> 32 </configuration>
3、创建工厂类(简化获取数据库对象和连接，也减少资源占用，直接调用内部方法)
1 package com.tree.utils;
2
3 import org.apache.ibatis.io.Resources;
4 import org.apache.ibatis.session.SqlSessionFactory;
5 import org.apache.ibatis.session.SqlSessionFactoryBuilder;
6
7 import java.io.IOException;
8 import java.io.InputStream;
9
10 public class SqlSessionFactoryUtils {
11 private static SqlSessionFactory sqlSessionFactory;
12
13 static {
14 //静态代码块会随着类的加载而自动执行，且只执行一次
15 try {
16 String resource = "mybatis-config.xml";
17 InputStream inputStream = Resources.getResourceAsStream(resource);
18 sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
19 } catch (IOException e) {
20 e.printStackTrace();
21 }
22 }
//调用getSqlSessionFactory方法23 public static SqlSessionFactory getSqlSessionFactory(){ 24 return sqlSessionFactory; 25 } 26 }
4.编写index.html和 jsp页面
index.html:
<a href="/A-lin/selectAllServlet">查询所有</a>
selectAll.jsp:
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<input type="button" value="新增" id="add">
<input type="button" value="刷新" id="refresh"><br>
<hr>
<table border="1" cellspacing="0" width="80%">
<tr>
<th>学号</th>
<th>姓名</th>
<th>年龄</th>
<th>操作</th>
</tr>
<c:forEach items="${students}" var="student">
<tr align="center">
<td id="${student.id}" name="id">${student.id}</td>
<td>${student.name}</td>
<td id="age">${student.age}</td>
<td><a href="/A-lin/selectByIdServlet?id=${student.id}">修改</a>
<a href="/A-lin/deleteByIdServlet?id=${student.id}">删除</a></td>
</tr>
</c:forEach>
</table>
<script>
document.getElementById("add").onclick = function () {
location.href = "addBrand.jsp";
}
document.getElementById("refresh").onclick = function () {
location.href = "/A-lin/selectAllServlet";
}
</script>
</body>
</html>
add.jsp:
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>添加信息</title>
</head>
<body>
<h3>添加信息</h3>
<form action="/A-lin/addServlet" method="post">
学号：<input name="id"><br>
姓名：<input name="name"><br>
年龄：<input name="age"><br>
<input type="submit" value="提交">
</form>
</body>
</html>
update.jsp:
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>修改信息</title>
</head>
<body>
<h3>修改信息</h3>
<form action="/A-lin/updateByIdServlet" method="get">
<input type="hidden" name="id" value="${student.id}">
姓名： <input readonly name="name" value="${student.name}"><br>
年龄: <input name="age" value="${student.age}"><br><br>
<input type="submit" value="提交">
</form>
</body>
</html>
二、创建类和接口
1、编写实体类entity（有参无参构造方法、toString方法、set、get方法）
public class Student {
private Integer id;
private String name;
private Integer age;
2、编写mapper接口和mapper.xml
1 public interface StudentMapper {
2
3 boolean add(Student student);
4
5 void deleteById(int id);
6
7 List<Student> selectAll();
8
9 Student selectById(int id);
10
11 void updateById(Student student);
1 <?xml version="1.0" encoding="UTF-8" ?>
2 <!DOCTYPE mapper
3 PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
4 "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
5 <mapper namespace="com.tree.mapper.StudentMapper">
6
7 <resultMap id="studentResultMap" type="Student">
8
9 </resultMap>
10
11 <!-- 增加-->
12 <insert id="add">
13 insert into student1 values (#{id},#{name},#{age});
14 </insert>
15
16 <!-- 根据id删除-->
17 <delete id="deleteById">
18 delete from student1 where id = #{id};
19 </delete>
20
21 <!-- 查询所有-->
22 <select id="selectAll" resultMap="studentResultMap">
23 select * from student1;
24 </select>
25 <select id="selectById" resultType="com.tree.entity.Student">
26 select * from student1 where id = #{id};
27 </select>
28 <!-- 更改年龄-->
29 <update id="updateById">
30 update student1 set age = #{age} where id = #{id};
31 </update>
32
33 </mapper>
3、创建service层，调用mapper接口的方法
1 package com.tree.service;
2
3 import com.tree.entity.Student;
4 import com.tree.mapper.StudentMapper;
5 import com.tree.utils.SqlSessionFactoryUtils;
6 import org.apache.ibatis.session.SqlSession;
7 import org.apache.ibatis.session.SqlSessionFactory;
8
9 import java.util.List;
10
11 /**
12 * @author Tree
13 * @date 2022/12/10 00:11
14 */
15 public class StudentService {
16
17 SqlSessionFactory factory = SqlSessionFactoryUtils.getSqlSessionFactory();
18
19 /**
20 * 增加
21 *
22 * @param student
23 * @return
24 */
25 public void add(Student student) {
26 //2. 获取SqlSession
27 SqlSession sqlSession = factory.openSession();
28 //3. 获取BrandMapper
29 StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
30 //4. 调用方法
31 mapper.add(student);
32 //5.提交并关闭事务
33 sqlSession.commit();
34 sqlSession.close();
35 }
36
37 /**
38 * 查询所有
39 */
40 public List<Student> selectAll() {
41 //2. 获取SqlSession
42 SqlSession sqlSession = factory.openSession();
43 //3. 获取BrandMapper
44 StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
45 //4. 调用方法
46 List<Student> students = mapper.selectAll();
47 //5.提交事务
48 sqlSession.close();
49
50 return students;
51 }
52
53 /**
54 * 查询id
55 */
56 public Student selectById(int id) {
57 //2. 获取SqlSession
58 SqlSession sqlSession = factory.openSession();
59 //3. 获取BrandMapper
60 StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
61 //4. 调用方法
62 Student student = mapper.selectById(id);
63 //5.提交事务关闭资源
64 sqlSession.close();
65 //返回对象
66 return student;
67 }
68
69
70 /**
71 * 修改年龄
72 */
73 public void updateById(Student student) {
74 //2. 获取SqlSession
75 SqlSession sqlSession = factory.openSession();
76 //3. 获取BrandMapper
77 StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
78 //4. 调用方法
79 mapper.updateById(student);
80 //5.提交并关闭事务
81 sqlSession.commit();
82 sqlSession.close();
83
84 }
85
86
87 /**
88 * 删除
89 *
90 * @param id
91 */
92 public void deleteById(int id) {
93 //2. 获取SqlSession
94 SqlSession sqlSession = factory.openSession();
95 //3. 获取BrandMapper
96 StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
97 //4. 调用方法
98 mapper.deleteById(id);
99 //5.提交并关闭事务
100 sqlSession.commit();
101 sqlSession.close();
102
103 }
104 }
4、创建servlet类，调用service文件
addServlet：
package com.tree.servlet;
import com.tree.entity.Student;
import com.tree.service.StudentService;
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.io.IOException;
@WebServlet("/addServlet")
public class addServlet extends HttpServlet {
private StudentService service = new StudentService();
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//处理POST请求的乱码问题
request.setCharacterEncoding("utf-8");
// 1.接收并设置参数
int id = Integer.parseInt(request.getParameter("id"));
String name = request.getParameter("name");
int age = Integer.parseInt(request.getParameter("age"));
Student student = new Student();
student.setId(id);
student.setName(name);
student.setAge(age);
// 2.调用BrandService完成查询
service.add(student);
// 3. 存入request域中
request.setAttribute("Student", student);
// 4. 转发到brand.jsp
request.getRequestDispatcher("/selectAllServlet").forward(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doGet(request, response);
}
}
deleteServlet
package com.tree.servlet;
import com.tree.service.StudentService;
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.io.IOException;
@WebServlet("/deleteByIdServlet")
public class deleteByIdServlet extends HttpServlet {
private StudentService service = new StudentService();
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//处理POST请求的乱码问题
request.setCharacterEncoding("utf-8");
// 1.接收参数
int id = Integer.parseInt(request.getParameter("id"));
System.out.println(id);
// 2.调用BrandService完成查询
service.deleteById(id);
// 4. 转发到brand.jsp
request.getRequestDispatcher("/selectAllServlet").forward(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doGet(request, response);
}
}
selectAll
1 package com.tree.servlet;
2
3
4 import com.tree.entity.Student;
5 import com.tree.service.StudentService;
6
7 import javax.servlet.ServletException;
8 import javax.servlet.annotation.WebServlet;
9 import javax.servlet.http.HttpServlet;
10 import javax.servlet.http.HttpServletRequest;
11 import javax.servlet.http.HttpServletResponse;
12 import java.io.IOException;
13 import java.util.List;
14
15 @WebServlet("/selectAllServlet")
16 public class selectAllServlet extends HttpServlet {
17 private StudentService service = new StudentService();
18
19 @Override
20 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
21 //处理POST请求的乱码问题
22 request.setCharacterEncoding("utf-8");
23
24 // 1.接收参数
25
26 // 2.调用BrandService完成查询
27 List<Student> students = service.selectAll();
28 // 3. 存入request域中
29 request.setAttribute("students", students);
30 // 4. 转发到brand.jsp
31 request.getRequestDispatcher("/selectAll.jsp").forward(request, response);
32 }
33
34 @Override
35 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
36 this.doGet(request, response);
37 }
38 }
selectById:
package com.tree.servlet;
import com.tree.entity.Student;
import com.tree.service.StudentService;
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.io.IOException;
import java.util.List;
@WebServlet("/selectByIdServlet")
public class selectByIdServlet extends HttpServlet {
private StudentService service = new StudentService();
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//处理POST请求的乱码问题
request.setCharacterEncoding("utf-8");
//1.接收参数
String id = request.getParameter("id");
// 2.调用BrandService完成查询
Student student = service.selectById(Integer.parseInt(id));
// 3. 存入request域中
request.setAttribute("student", student);
// 4. 转发到brand.jsp
request.getRequestDispatcher("/updateStudent.jsp").forward(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doGet(request, response);
}
}
update:
package com.tree.servlet;
import com.tree.entity.Student;
import com.tree.service.StudentService;
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.io.IOException;
import java.util.List;
@WebServlet("/updateByIdServlet")
public class updateByIdServlet extends HttpServlet {
private StudentService service = new StudentService();
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//处理POST请求的乱码问题
request.setCharacterEncoding("utf-8");
// 1.接收参数
String id = request.getParameter("id");
String name = request.getParameter("name");
String age = request.getParameter("age");
//设置参数
Student student = new Student();
student.setId(Integer.valueOf(id));
student.setName(name);
student.setAge(Integer.valueOf(age));
// 2.调用BrandService完成查询
service.updateById(student);
// 4. 转发到brand.jsp
request.getRequestDispatcher("/selectAllServlet").forward(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doGet(request, response);
}
}
成品页面很简陋就不放出来了，其实写好之后算是一个模板，以后有差不多的直接套用，兜兜转转也一年了
标签：JavaWeb,request,改查,javax,student,增删,import,servlet,id From： https://www.cnblogs.com/changeyi/p/16971830.html