IDE:idea
框架:maven + mybatis + tomcat
具体的文件分布
需要的配置文件
maven的pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><groupId>com.stdu</groupId><artifactId>NewClasses</artifactId><version>1.0-SNAPSHOT</version><!-- 默认打包为war包--><packaging>war</packaging><dependencies><dependency><!-- 导入Servlet API--><groupId>javax.servlet</groupId><artifactId>javax.servlet-api</artifactId><version>3.1.0</version><scope>provided</scope></dependency><dependency><groupId>org.mybatis</groupId><artifactId>mybatis</artifactId><version>3.5.5</version></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>8.0.25</version></dependency><dependency><groupId>commons-io</groupId><artifactId>commons-io</artifactId><version>2.6</version></dependency><dependency><groupId>javax.servlet.jsp</groupId><artifactId>javax.servlet.jsp-api</artifactId><version>2.3.3</version><scope>provided</scope></dependency><!-- https://mvnrepository.com/artifact/jstl/jstl --><dependency><groupId>jstl</groupId><artifactId>jstl</artifactId><version>1.2</version></dependency><!-- https://mvnrepository.com/artifact/taglibs/standard --><dependency><groupId>taglibs</groupId><artifactId>standard</artifactId><version>1.1.2</version></dependency></dependencies><properties><maven.compiler.source>1.8</maven.compiler.source><maven.compiler.target>1.8</maven.compiler.target><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding></properties><build><plugins><!-- tomcat 插件--><plugin><groupId>org.apache.tomcat.maven</groupId><artifactId>tomcat7-maven-plugin</artifactId><version>2.2</version><configuration><port>80</port><!-- <path>/</path>--></configuration></plugin></plugins></build></project>
mybatis的mybatis-config.xml文件
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration><environments default="development"><environment id="development"><transactionManager type="JDBC"/><dataSource type="POOLED"><property name="driver" value="com.mysql.jdbc.Driver"/><property name="url" value="jdbc:mysql:///test?useSSL=false&allowPublicKeyRetrieval=true"/><property name="username" value="root"/><property name="password" value="123456"/></dataSource></environment></environments><mappers><package name="com.stdu"/>
<!-- <mapper resource="UserMapper.xml"/>--></mappers>
</configuration>
具体步骤
- 首先,创建课程实体类
package com.stdu.pojo;public class Lesson {private String lesson;private String teacher;private String place;public Lesson() {}public Lesson(String lesson, String teacher, String place) {this.lesson = lesson;this.teacher = teacher;this.place = place;}/*** 获取* @return lesson*/public String getLesson() {return lesson;}/*** 设置* @param lesson*/public void setLesson(String lesson) {this.lesson = lesson;}/*** 获取* @return teacher*/public String getTeacher() {return teacher;}/*** 设置* @param teacher*/public void setTeacher(String teacher) {this.teacher = teacher;}/*** 获取* @return place*/public String getPlace() {return place;}/*** 设置* @param place*/public void setPlace(String place) {this.place = place;}public String toString() {return "Lesson{lesson = " + lesson + ", teacher = " + teacher + ", place = " + place + "}";}
}- 建立数据库表(名称尽量和java实体类的名称一致)
create table lesson(id int primary key auto_increment,lesson varchar(30),teacher varchar(30),place varchar(30)
);
- 建立前端html界面
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>Title</title>
</head>
<body><center><!-- 添加课程的表单 --><h1>添加课程</h1>
<!-- action: 表单提交的地址--><form action="http://localhost/NewClasses/commit" method = 'post' style="text-align: center;">课程名称: <input type="text" name="lesson"><br>老师姓名: <input type="text" name="teacher"><br>上课地点: <input type="text" name="place"><br><input type="submit" value="提交"></form>
</center></body>
</html>- LessonMapper接口和LessonMapper.xml
在这两个文件中书写添加的sql语句
深入解析 Mybatis 中 Mapper 接口的实现原理
package com.stdu.mapper;import com.stdu.pojo.Lesson;
import org.apache.ibatis.annotations.Insert;/*** LessonMapper接口用于定义与数据库中lesson表相关的数据操作方法*/
public interface LessonMapper {/*** 插入一个新的lesson记录到数据库中* * @param l Lesson对象，包含要插入的lesson、teacher和place字段* * 使用MyBatis的@Insert注解来执行插入操作，注解内的SQL语句用于指定插入的字段和值* 这里的#{lesson}, #{teacher}, #{place}是参数占位符，它们将被Lesson对象的相应属性值替换*/@Insert("insert into lesson(lesson,teacher,place) values(#{lesson},#{teacher},#{place})")void insert(Lesson l);
}上面是直接在接口里使用MyBatis的@Insert注解来执行插入操作,也可以写在LessonMapper.xml文件中,如下
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.stdu.mapper.LessonMapper"><insert id="insert" >insert into lesson(lesson,teacher,place) values(#{lesson},#{teacher},#{place})</insert></mapper>
- 最主要的Servlet代码
用来获取到前端输入框的内容和连接数据库
package com.stdu.web;import com.stdu.mapper.LessonMapper;
import com.stdu.pojo.Lesson;
import com.stdu.util.SqlSessionFactoryUtils;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;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.io.InputStream;// 处理"/commit"路径的HTTP请求
@WebServlet("/commit")
public class a01Servlet extends HttpServlet {/*** 处理GET请求的方法* * @param req 用于获取请求信息的HttpServletRequest对象* @param resp 用于发送响应信息的HttpServletResponse对象* @throws ServletException 如果Servlet遇到异常* @throws IOException 如果发生输入或输出异常*/@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {//解决乱码问题req.setCharacterEncoding("utf-8");resp.setHeader("content-type","text/html;charset=utf-8");// 获取请求参数中的课程、教师和地点信息String l = req.getParameter("lesson");String t = req.getParameter("teacher");String p = req.getParameter("place");// 加载MyBatis配置文件String resource = "mybatis-config.xml";InputStream inputStream = Resources.getResourceAsStream(resource);// 构建SqlSessionFactory对象，用于获取SqlSessionSqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);SqlSession sqlSession = sqlSessionFactory.openSession();// 获取LessonMapper接口的实现类对象，用于执行数据库操作LessonMapper mapper = sqlSession.getMapper(LessonMapper.class);// 插入新的课程信息到数据库，并提交事务mapper.insert(new Lesson(l,t,p));sqlSession.commit();// 向客户端发送添加成功的响应信息resp.getWriter().write("添加成功!");}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {//post请求也调用doGet方法this.doGet(req, resp);}
}结果展示
查看数据库,添加成功
