0.写在前面(对mybatis,spring的理解)（不看可跳过）

0.1 为什么需要mybatis

1.传统的jdbc代码，有很多重复的代码块。比如：数据取出时候的封装，数据库的建立连接等，操作非常繁琐…,通过框架可以减少重复代码，提高开发效率
2.为什么需要编写一个工具类，获得sqlSession对象？答：用于执行 SQL 语句、管理数据库连接、事务以及缓存
3.mybatis通过xml语句实现数据的增删改查
4.使用流程：4.1写好映射接口，UserMapper.java，4.2.写好对应的映射文件(增删改查语句，结果集)usermapper.xml 4.3mybatis-config.xml引用该配置文件 4.3 sqlsesion访问usermapper接口调用方法

0.2 为什么需要spring

1.对于一个实体类，无需创建对象，通过简单的bean配置就能实现对象的创建
2.支持注解。直接再某个类上面使用@Component,对应的Bean就不需要写了，简化代码
3.支持自动装配，某个类里面引用了其他类，再其他类上面加一个@Autowired,就需要再bean里面用ref引用了
4.配置数据源，帮mybatis完成这项工作

0.3为什么需要springmvc

1.后端的数据方便直接封装和返回给前端界面

1.新建ssmbuild数据库

1.打开Navicat
2.点击新建查询
3.输入一下语句代码

CREATE DATABASE `ssmbuild`;USE `ssmbuild`;DROP TABLE IF EXISTS `books`;CREATE TABLE `books` (`bookID` INT(10) NOT NULL AUTO_INCREMENT COMMENT '书id',`bookName` VARCHAR(100) NOT NULL COMMENT '书名',`bookCounts` INT(11) NOT NULL COMMENT '数量',`detail` VARCHAR(200) NOT NULL COMMENT '描述',KEY `bookID` (`bookID`)
) ENGINE=INNODB DEFAULT CHARSET=utf8INSERT INTO `books` (`bookID`, `bookName`, `bookCounts`, `detail`) VALUES
(1, 'Java', 1, '从入门到放弃'),
(1, 'MySQL', 10, '从删库到跑路'),
(3, 'Linux', 5, '从入门到坐牢');

2.新建Maven项目

2.1 操作步骤

2.2 初始项目结构

3.初始化步骤

3.1 配置下载maven依赖，构建资源导出

  <!--依赖, junit, 连接池,servlet,jsp,mybatis,mybatis-spring,spring,--><dependencies><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.13.2</version></dependency><!--数据库驱动--><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>8.0.24</version></dependency><!--数据库连接池--><dependency><groupId>com.mchange</groupId><artifactId>c3p0</artifactId><version>0.9.5.2</version></dependency><!--Servlet JSP--><dependency><groupId>javax.servlet</groupId><artifactId>servlet-api</artifactId><version>2.5</version></dependency><dependency><groupId>javax.servlet.jsp</groupId><artifactId>jsp-api</artifactId><version>2.2</version></dependency><dependency><groupId>javax.servlet</groupId><artifactId>jstl</artifactId><version>1.2</version></dependency><!--Mybatis--><dependency><groupId>org.mybatis</groupId><artifactId>mybatis</artifactId><version>3.5.2</version></dependency><dependency><groupId>org.mybatis</groupId><artifactId>mybatis-spring</artifactId><version>2.0.2</version></dependency><!--Spring--><dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>5.2.0.RELEASE</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-jdbc</artifactId><version>5.2.0.RELEASE</version></dependency></dependencies><!--静态资源导出问题--><build><resources><resource><directory>src/main/java</directory><includes><include>**/*.properties</include><include>**/*.xml</include></includes><filtering>false</filtering></resource><resource><directory>src/main/resources</directory><includes><include>**/*.properties</include><include>**/*.xml</include></includes><filtering>false</filtering></resource><resource><directory>src/main/resources</directory><includes><include>**/*.properties</include><include>**/*.xml</include></includes><filtering>false</filtering></resource></resources></build>

3.2 连接数据库

3.3建包，建mybatis，数据库和spring配置文件

mybatis-config.xml文件代码

<?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><!--配置数据源，交给Spring去做--><typeAliases><package name="com.aloha.pojo"/></typeAliases>
</configuration>

applicationContext.xml文件代码

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsd">
</beans>

database.properties代码文件

jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/ssmbuild?useSSL=false&useUnicode=true&characterEncoding=utf8&serverTimezone=UTC
jdbc.username=root
jdbc.password=123456

4.配置dao,service，pojo包下的文件

结构如下

4.1新建实体类Books

新建pojo中Books实体类

package com.aloha.pojo;import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;@Data
@AllArgsConstructor
@NoArgsConstructor
public class Books {private int bookID;private String bookName;private int bookCounts;private String detail;
}

4.2新建dao接口和对应xml文件

BookMapper

package com.aloha.dao;import com.aloha.pojo.Books;
import org.apache.ibatis.annotations.Param;import java.awt.print.Book;
import java.util.List;public interface BookMapper {// 增加一本书int addBook(Books books);// 删除一本书int deleteBookById(@Param("bookId") int id);// 更新一本书int updateBook(Books books);// 查询一本书Books queryBookById(@Param("bookId") int id);// 查询全部的书List<Books> queryAllBooks();
}

BookMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.aloha.dao.BookMapper"><insert id="addBook" parameterType="Books">insert into ssmbuild.books (bookName, bookCounts, detail)values (#{bookName}, #{bookCounts}, #{detail})</insert><delete id="deleteBookById" parameterType="int">delete from ssmbuild.books where bookID = #{bookId}</delete><update id="updateBook" parameterType="Books">update ssmbuild.booksset bookName=#{bookName}, bookCounts=#{bookCounts}, detail=#{detail}where bookID=#{bookID}</update><select id="queryBookById" resultType="Books">select * from ssmbuild.books where bookID = #{bookId}</select><select id="queryAllBooks" resultType="Books">select * from ssmbuild.books</select>
</mapper>

4.3新建service接口和实现类

BookService

package com.aloha.service;import com.aloha.pojo.Books;
import org.apache.ibatis.annotations.Param;import java.util.List;public interface BookService {// 增加一本书int addBook(Books books);// 删除一本书int deleteBookById(int id);// 更新一本书int updateBook(Books books);// 查询一本书Books queryBookById(int id);// 查询全部的书List<Books> queryAllBooks();
}

BookServiceImpl

package com.aloha.service;import com.aloha.dao.BookMapper;
import com.aloha.pojo.Books;import java.util.Collections;
import java.util.List;public class BookServiceImpl implements BookMapper {// service调dao层，业务层调用dao层就对了：组合Daoprivate BookMapper bookMapper;public void setBookMapper(BookMapper bookMapper) {this.bookMapper = bookMapper;}@Overridepublic int addBook(Books books) {return bookMapper.addBook(books);}@Overridepublic int deleteBookById(int id) {return bookMapper.deleteBookById(id);}@Overridepublic int updateBook(Books books) {return bookMapper.updateBook(books);}@Overridepublic Books queryBookById(int id) {return bookMapper.queryBookById(id);}@Overridepublic List<Books> queryAllBooks() {return bookMapper.queryAllBooks();}
}

5.配置spring-dao.xml和spring-service.xml文件

resources文件目录下的spring-dao.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context-4.0.xsd"><!--1.关联数据库配置文件--><context:property-placeholder location="classpath:database.properties"/><!--2.连接池dbcp: 半自动化，不能自动链接c3p0：自动化操作（自动化加载配置文件，并且可以自动设置到对象中）druidhikari--><bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"><property name="driverClass" value="${jdbc.driver}"/><property name="jdbcUrl" value="${jdbc.url}"/><property name="user" value="${jdbc.username}"/><property name="password" value="${jdbc.password}"/><!-- c3p0连接池的私有属性 --><property name="maxPoolSize" value="30"/><property name="minPoolSize" value="10"/><!-- 关闭连接后不自动commit --><property name="autoCommitOnClose" value="false"/><!-- 获取连接超时时间 --><property name="checkoutTimeout" value="10000"/><!-- 当获取连接失败重试次数 --><property name="acquireRetryAttempts" value="2"/></bean><!--3.sqlSessionFactory--><bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"><property name="dataSource" ref="dataSource"/><!--绑定Mybatis配置文件--><property name="configLocation" value="classpath:mybatis-config.xml"/></bean><!--配置dao接口扫描包，动态实现Dao接口可以注入到Spring容器中--><!--意思是这个配置文件，mapper接口就不需要使用bean注入了--><bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"><!--注入sqlSessionFactory--><property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/><!--要扫描的dao包--><property name="basePackage" value="com.aloha.dao"/></bean></beans>

spring-service.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context-4.0.xsd"><!--1.扫描service下的包，将它们自动注册为 Spring 容器的 Bean--><context:component-scan base-package="com.aloha.service"/><!--2.将我们所有的业务类，注入到Spring,可以通过配置或注解实现--><bean id="bookServiceImpl" class="com.aloha.service.BookServiceImpl"><property name="bookMapper" ref="bookMapper"/></bean><!--3.声明式事务配置--><bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"><!--注入数据源--><property name="dataSource" ref="dataSource"/></bean><!--4.aop事务支持--></beans>

ApplicationContext进行关联

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsd"><import resource="classpath:spring-dao.xml"/><import resource="classpath:spring-service.xml"/>
</beans>

6.spring-mvc相关配置

6.1配置web.xml

<?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"><!--DispatchServlet--><servlet><servlet-name>springmvc</servlet-name><servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class><init-param><param-name>contextConfigLocation</param-name><param-value>classpath:applicationContext.xml</param-value></init-param><load-on-startup>1</load-on-startup></servlet><servlet-mapping><servlet-name>springmvc</servlet-name><url-pattern>/</url-pattern></servlet-mapping><!--乱码过滤--><filter><filter-name>encondingFilter</filter-name><filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class><init-param><param-name>encoding</param-name><param-value>utf-8</param-value></init-param></filter><filter-mapping><filter-name>encondingFilter</filter-name><url-pattern>/*</url-pattern></filter-mapping><!--Session--><session-config><session-timeout>15</session-timeout></session-config></web-app>

6.2配置spring-mvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:mvc="http://www.springframework.org/schema/mvc"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-4.0.xsdhttp://www.springframework.org/schema/mvchttp://www.springframework.org/schema/mvc/spring-mvc-4.0.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context-4.0.xsd"><!--1.注解驱动，这些功能涉及 Web 层的请求映射、数据绑定和响应处理。处理映射器，处理器适配器--><mvc:annotation-driven/><!--2.静态资源过滤--><mvc:default-servlet-handler/><!--3.扫描包controller，将该类自动注册为 Spring 容器的 Bean--><context:component-scan base-package="com.aloha.controller"/><!--4.视图解析器--><bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"><property name="prefix" value="/WEB-INF/jsp/"/><property name="suffix" value=".jsp"/></bean></beans>

最后

7.编写Controller文件

package com.aloha.controller;import com.aloha.pojo.Books;
import com.aloha.service.BookService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;import javax.annotation.Resource;
import java.util.List;@Controller
@RequestMapping("/book")
public class BookController {// controller 调 service层@Autowired@Resourceprivate BookService bookService;  // 属性自动注入@RequestMapping("/allBook")public String list(Model model) {List<Books> list = bookService.queryAllBooks();model.addAttribute("list", list);return "allBook";  // 返回的jsp界面}}

8.前端界面渲染

index.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<body>
<h2>Hello World!</h2>
<style>a {text-decoration: none;color: black;}h3 {width: 180px;height: 38px;margin: 100px auto;text-align: center;line-height: 38px;background: deepskyblue;border-radius: 5px;}
</style>
</body><h3><a href="${pageContext.request.contextPath}/book/allBook">进入书籍界面</a>
</h3>
</html>

jsp/allBook.jsp

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%--Created by IntelliJ IDEA.User: alohaDate: 2024/11/30Time: 11:28To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head><title>书籍展示</title><!--Bootsthap美化界面--><link href="https://cdn.staticfile.org/twitter-bootsthap/3.3.7/css/bootsthap.min.css" rel="stylesheet">
</head>
<body>
<div class="continer"><div class="row clearfix"><div class="col-md-12 column"><div class="page-header"><small>书籍列表 ------ 显示所有书籍</small></div></div><div class="row clearfix"><div class="col-md-12 column"><table class="table table-hover table-striped"><thead><tr><th>书籍编号</th><th>书籍名称</th><th>书籍数量</th><th>书籍详情</th></tr></thead><tbody><c:forEach var="book" items="${list}"><tr><td>${book.bookID}</td><td>${book.bookName}</td><td>${book.bookCounts}</td><td>${book.detail}</td></tr></c:forEach></tbody></table></div></div></div>
</div></body>
</html>

渲染结果

成功！！！！