B站狂神说Mybatis+Spring+SpringMVC整合理解(ssm框架整合)

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=utf8

INSERT 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 configuration
        PUBLIC "-//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/beans
                           http://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 mapper
        PUBLIC "-//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.books
        set 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Dao
    private BookMapper bookMapper;

    public void setBookMapper(BookMapper bookMapper) {
        this.bookMapper = bookMapper;
    }

    @Override
    public int addBook(Books books) {
        return bookMapper.addBook(books);
    }

    @Override
    public int deleteBookById(int id) {
        return bookMapper.deleteBookById(id);
    }

    @Override
    public int updateBook(Books books) {
        return bookMapper.updateBook(books);
    }

    @Override
    public Books queryBookById(int id) {
        return bookMapper.queryBookById(id);
    }

    @Override
    public 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/beans
                           http://www.springframework.org/schema/beans/spring-beans.xsd
                           http://www.springframework.org/schema/context
                           http://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）
        druid
        hikari
    -->
    <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/beans
                           http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
                           http://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/beans
                           http://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/beans
                           http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
                           http://www.springframework.org/schema/mvc
                           http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd
                           http://www.springframework.org/schema/context
                           http://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
    @Resource
    private 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: aloha
  Date: 2024/11/30
  Time: 11:28
  To 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！！！！