1.pom配置

<dependencies>标准配置

<!--标准模板-->
    <dependencies>
        <!--Junit-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <!--数据库驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <!-- 数据库连接池 dbcp-->
        <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>5.1.9.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.1.9.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.16.10</version>
        </dependency>
    </dependencies>

静态资源导出配置

<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>
    </resources>
</build>

2.mybatis配置

首先需要一个pojo类以及对应的mapper接口和mapper.xml

mapper.xml 用来写sql语句

mapper接口类需要和它对应

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">


<mapper namespace="com.alibaba.dao.BookMapper">
    <select id="queryAllBook" resultType="Books">
        select * from books;
    </select>
</mapper>

mybatis-config.xml

这个文件可以直接整合到spring的配置文件spring-dao.xml中，删掉也没有关系

<?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>
    <typeAliases>
        <package name="com.alibaba.pojo"/>
    </typeAliases>
    <mappers>
        <mapper class="com.alibaba.dao.BookMapper"/>
    </mappers>
</configuration>

database.properties

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

spring-dao.xml

spring-dao.xml就实现了 dao层的功能读取这个配置文件即可拿到 mapper去访问数据库

<?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
       https://www.springframework.org/schema/context/spring-context.xsd">

    <context:property-placeholder location="db.properties"/>


    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="jdbcUrl" value="${jdbc.url}"/>
        <property name="driverClass" value="${jdbc.driver}"/>
        <property name="user" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>

    </bean>

    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="typeAliases" value="com.alibaba.pojo.Books"/>
        <property name="mapperLocations" value="com/alibaba/dao/BookMapper.xml"/>
    </bean>


    <!-- 4.配置扫描Dao接口包，动态实现Dao接口注入到spring容器中 -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!-- 注入sqlSessionFactory -->
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        <!-- 给出需要扫描Dao接口包 -->
        <property name="basePackage" value="com.alibaba.dao"/>
    </bean>

</beans>

到现在dao层的代码基本实现，也就是说我们可以拿到mapper去访问数据库，实现基本的增删改查了。

mybatis层代码测试

@Test
public void test(){
    ApplicationContext context = new ClassPathXmlApplicationContext("spring-dao.xml");
    BookMapper mapper = (BookMapper) context.getBean("bookMapper");
    List<Books> books = mapper.queryAllBook();

    System.out.println(books);
}

3.springMVC

service层的代码+处理器的代码（controller）

controller就可以处理前端的请求，调用service层，service层再调用dao层的mapper去访问数据库，

那么这就需要写一个配置文件，将mapper注入到service层，使得业务层可以调用mapper访问数据库

先把spring-mvc的配置写好，这个主要是为了让controller正常工作

<?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"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       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.xsd
   http://www.springframework.org/schema/mvc
   https://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <!-- 配置SpringMVC -->
    <!-- 1.开启SpringMVC注解驱动 -->
    <mvc:annotation-driven />
    <!-- 2.静态资源默认servlet配置-->
    <mvc:default-servlet-handler/>

    <!-- 3.配置jsp 显示ViewResolver视图解析器 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
        <property name="prefix" value="/WEB-INF/jsp/" />
        <property name="suffix" value=".jsp" />
    </bean>

    <!-- 4.扫描web相关的bean -->
    <context:component-scan base-package="com.alibaba.controller" />

</beans>

接着写好 spring-service.xml，是为了把dao层和service层连接到一起

<?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.xsd">

    <import resource="spring-dao.xml"/>
    <!-- 扫描service相关的bean -->
    <context:component-scan base-package="com.alibaba.service" />

    <!--BookServiceImpl注入到IOC容器中-->
    <bean id="BookServiceImpl" class="com.alibaba.service.BookServiceImpl">
        <property name="bookMapper" ref="bookMapper"/>
    </bean>

    <!-- 配置事务管理器 -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <!-- 注入数据库连接池 -->
        <property name="dataSource" ref="dataSource" />
    </bean>

</beans>

web.xml配置（只有一个DispatcherServlet）

<?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">
    <!--DispatcherServlet-->
    <servlet>
        <servlet-name>DispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <!--一定要注意:我们这里加载的是总的配置文件，之前被这里坑了！-->
            <param-value>classpath:application.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>DispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

</web-app>

4.application.xml大一统

<?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="spring-dao.xml"/>
    <import resource="spring-mvc.xml"/>
    <import resource="spring-service.xml"/>

</beans>