项目与模块下载

任务：

将springmvc_ssm这个ssm整合后的项目拆分成四个模块，如下图：

ssm_pojo拆分

新建模块

 从原始项目中拷贝实体类（User）到该模块

ssm_dao拆分

新建模块

从原始项目中拷贝相关内容到该模块

• 数据层接口（UserDao）
• 配置文件：3个

注意：分页插件在配置中与SqlSessionFactoryBean绑定，需要保留，如下：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       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
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">

    <!--开启bean注解扫描-->
    <context:component-scan base-package="com.itheima"/>

    <!--加载properties文件-->
    <context:property-placeholder location="classpath*:jdbc.properties"/>

    <!--数据源-->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="driverClassName" value="${jdbc.driver}"/>
        <property name="url" value="${jdbc.url}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
    </bean>

    <!--整合mybatis到spring中-->
    <bean class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="typeAliasesPackage" value="com.itheima.domain"/>
        <!--分页插件-->
        <property name="plugins">
            <array>
                <bean class="com.github.pagehelper.PageInterceptor">
                    <property name="properties">
                        <props>
                            <prop key="helperDialect">mysql</prop>
                            <prop key="reasonable">true</prop>
                        </props>
                    </property>
                </bean>
            </array>
        </property>
    </bean>

    <!--映射扫描-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.itheima.dao"/>
    </bean>

</beans>

•  pom.xml:事先对ssm_pojo模块执行install指令，将其安装到本地仓库，再引入数据层相关坐标即可，删除springmvc相关坐标，具体依赖如下：

<!--导入资源文件pojo-->
        <dependency>
            <groupId>com.itheima</groupId>
            <artifactId>ssm_pojo</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>

        <!--spring环境-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.3.19</version>
        </dependency>

        <!--mybatis环境-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.6</version>
        </dependency>
        <!--mysql环境-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.28</version>
        </dependency>
        <!--spring整合jdbc-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.3.12</version>
        </dependency>
        <!--spring整合mybatis-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.6</version>
        </dependency>
        <!--druid连接池-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.22</version>
        </dependency>
        <!--分页插件坐标-->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper</artifactId>
            <version>5.1.6</version>
        </dependency>

ssm_service拆分

新建模块

从原始项目中拷贝相关内容到该模块

• 业务层接口和实现类（UserService、UserServiceImpl）
• 配置文件：applicationContext-service.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx"
       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
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">

    <!--开启bean注解扫描-->
    <context:component-scan base-package="com.itheima"/>

    <!--开启注解式事务-->
    <tx:annotation-driven transaction-manager="txManager"/>

    <!--事务管理器-->
    <bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>

</beans>

• pom.xml

        <!--导入资源文件dao-->
        <dependency>
            <groupId>com.itheima</groupId>
            <artifactId>ssm_dao</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
    
        <!--spring环境-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.3.12</version>
        </dependency>

        <!--junit单元测试-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13.2</version>
        </dependency>

        <!--spring整合junit-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>5.3.19</version>
        </dependency>

•  修改单元测试引入的配置文件名称，又单个文件修改为多个：

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {"classpath:applicationContext-service.xml","classpath:applicationContext-dao.xml"})
public class UserServiceTest {

ssm_controller拆分 

 新建模块（使用webapp模板）

从原始项目中拷贝相关内容到该模块

• 表现层控制器类与相关设置类（UserController、异常相关。。。）
• 配置文件：保留与表现层相关配置文件（spring-mvc.xml）、服务器相关配置文件（web.xml),如下：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       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
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">

    <mvc:annotation-driven/>
    <context:component-scan base-package="com.itheima.controller"/>

</beans>

<?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_3_1.xsd"
         version="3.1">

  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath*:applicationContext-*.xml</param-value>
  </context-param>

  <!--启动服务器时，通过监听器加载spring运行环境-->
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>

  <filter>
    <filter-name>CharacterEncodingFilter</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>CharacterEncodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

  <servlet>
    <servlet-name>DispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath*:spring-mvc.xml</param-value>
    </init-param>
  </servlet>
  <servlet-mapping>
    <servlet-name>DispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

</web-app>

注意：修改了web.xml中加载spring环境的配置文件名称，使用*通配符，加载所有applicationContext-开头的配置文件。

• pom.xml:

    <dependency>
      <groupId>com.itheima</groupId>
      <artifactId>ssm_service</artifactId>
      <version>1.0-SNAPSHOT</version>
    </dependency>

    <!--springmvc环境-->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>5.3.19</version>
    </dependency>
    <!--jackson相关坐标3个-->
    <dependency>
      <groupId>com.fasterxml.jackson.core</groupId>
      <artifactId>jackson-databind</artifactId>
      <version>2.9.0</version>
    </dependency>
    <!--<dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>2.9.0</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-annotations</artifactId>
        <version>2.9.0</version>
    </dependency>-->
    <!--servlet环境-->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>4.0.1</version>
      <scope>provided</scope>
    </dependency>

分模块开发总结：

1、模块中仅包含当前模块对应的功能类与配置文件

2、spring核心配置文件根据模块功能不同进行独立制作

3、被依赖的模块要安装到本地仓库，其他模块才能使用其坐标。

4、web.xml需要加载所有的spring核心配置文件