ssm整合

1. SSM是什么?

• web层的解决方案

  • SpringMvc

• Service层的解决方案

  • Spring

• Dao层的解决方案

  • mybatis

2.开发项目的流程

Dao--->Service--->Web

---

3.mybatis与Spring的整合

3.1 依赖POM

<?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.xzy</groupId>
  <artifactId>ssm</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>

    <dependencies>
        <!--junit4的依赖-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>


        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.10</version>
        </dependency>


        <!--返回的对象转换成json字符串必须导入jackson的依赖-->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.11.0</version>
        </dependency>

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.11.0</version>
        </dependency>

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.11.0</version>
        </dependency>

        
        <!--log4j的依赖-->
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>

        <!--mysql的依赖-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.22</version>
        </dependency>


        <!--c3p0连接池-->
        <dependency>
            <groupId>com.mchange</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.5.2</version>
        </dependency>


        <!--mybatis依赖-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.4.4</version>
        </dependency>


        <!--spring整合mybatis的依赖-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>1.3.1</version>
        </dependency>

        <!--Spring的jdbc模块-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.2.1.RELEASE</version>
        </dependency>


        <!--导入spring的依赖-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.2.1.RELEASE</version>
        </dependency>

        <!--Spring整合单元测试的依赖-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>5.2.1.RELEASE</version>
        </dependency>

    </dependencies>

    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
        </resources>
    </build>

</project>

3.2 创建mybatis的配置文件(mybatis-conf.xml)

<?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>

    <settings>
        <!-- 打印sql语句 -->
        <setting name="logImpl" value="STDOUT_LOGGING" />
    </settings>

    <!-- 起别名 -->
    <typeAliases>
        <package name="com.xzy.ssm.entity"/>
    </typeAliases>
    <!--在此不需要的原因是,我们在Spring中使用了c3p0的连接池对象-->
    <!--<environments default="development">-->
    <!--<environment id="development">-->
    <!--<transactionManager type="JDBC"></transactionManager>-->
    <!--<dataSource type="POOLED">-->
    <!--<property name="driver" value="com.mysql.jdbc.Driver"/>-->
    <!--<property name="url" value="jdbc:mysql://localhost:3306/up2?characterEncoding=utf8"/>-->
    <!--<property name="username" value="root"/>-->
    <!--<property name="password" value="root"/>-->
    <!--</dataSource>-->
    <!--</environment>-->
    <!--</environments>-->

    <mappers>
        <!--不需要的原因是,Spring中使用了mapper扫描器-->
        <!--<package name="com.uplooking.ssm.mapper"></package>-->
    </mappers>



</configuration>

3.3 编写mapper

UserMapper.java

package com.uplooking.ssm.mapper;
import com.uplooking.ssm.pojo.User;
import org.springframework.stereotype.Repository;
@Repository
public interface UserMapper {
    User findUserById(Integer id);
}

UserMapper.xml

<?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.uplooking.ssm.mapper.UserMapper">
    <select id="findUserById" resultType="user" parameterType="int">
        select * from user where id=#{value}
    </select>
</mapper>

3.4 创建pojo类

package com.uplooking.ssm.pojo;
public class User {
    private Integer id;
    private String name;
    private Integer age;
    private Integer aid;

    @Override
    public String toString() {
        return "User{" +
            "id=" + id +
            ", name='" + name + '\'' +
            ", age=" + age +
            ", aid=" + aid +
            '}';
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public Integer getAid() {
        return aid;
    }

    public void setAid(Integer aid) {
        this.aid = aid;
    }
}

3.5 创建Spring的配置文件(applicationContext.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.xsd">

    <!--Spring的注解扫描器-->
    <context:component-scan base-package="com.uplooking.ssm"/>

    <!-- 配置c3p0连接池 -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver"/>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/up2?characterEncoding=utf8"/>
        <property name="user" value="root"/>
        <property name="password" value="root"/>
    </bean>

    <!--mybatis整合spring-->
    <bean name="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation" value="classpath:mybatis-conf.xml"/>
         <!-- 如果mapper对应的xml没有和接口在同一个包下,那么需要指定mapper对应的xml路径,如果在同一个包下,这不需要指定mapperLocations属性-->
        <property name="mapperLocations" value="classpath:/mappers/*.xml"></property>
    </bean>

    <!--mapper扫描器    bean的id为mapper类名首字母小写-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
      	<!--指定mapper接口所在的包路径-->  
      	<property name="basePackage" value="com.uplooking.ssm.mapper"/>
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
    </bean>
</beans>

3.6 编写Service

@Service
public class UserService {
    @Autowired
    private UserMapper userMapper;

    public User findUserById(Integer id) {
        User user = userMapper.findUserById(1);
        return user;
    }
}

3.7 测试Mapper

@RunWith(SpringRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class UserMapperTest {
    @Autowired
    private UserMapper userMapper;

    @Test
    public void testFindUserById() {
        userMapper.findUserById(1);
    }
}

3.8 测试Service

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class UserServiceTest {
    @Autowired
    private UserService userService;
    
    @Test
    public void testFindUserById() {
        User user = userService.findUserById(1);
        System.out.println(user);
    }
}

4. SpringMvc与Spring的整合

4.1 创建springmvc.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"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       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/aop
                           http://www.springframework.org/schema/aop/spring-aop.xsd
                           http://www.springframework.org/schema/tx
                           http://www.springframework.org/schema/tx/spring-tx.xsd
                           http://www.springframework.org/schema/mvc
                           http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <!--高级功能注解的扩展支持(一定要放在其他配置的最前面,要不然不生效)-->
    <mvc:annotation-driven></mvc:annotation-driven>
    <!--配置前端控制器(在web.xml中配置)-->
    <!--配置处理器映射器-->
    <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping"/>
    <!--处理器适配器-->
    <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter"/>
    <!--配置视图解析器-->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"/>
    <!--包扫描-->
    <context:component-scan base-package="com.xzy.ssm.controller"/>
</beans>

4.2 编写Controller

@Controller
@RequestMapping("/user")
public class UserController {
    @Autowired
    private UserService userService;

    @RequestMapping("/findUserById")
    public ModelAndView findUserById(HttpServletRequest request, HttpServletResponse response, Integer id) {
        ModelAndView modelAndView = new ModelAndView();
        modelAndView.setViewName("/user.jsp");
        User user = userService.findUserById(id);
        modelAndView.addObject("user", user);
        return modelAndView;
    }
}

4.3 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_3_1.xsd"
         version="3.1">
    <!--ServletContext创建时加载Spring工厂-->
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:applicationContext.xml</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>


    <!--当访问*.action时加载springmvc-->
    <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:springmvc.xml</param-value>
        </init-param>
    </servlet>

    <servlet-mapping>
        <servlet-name>dispatcherServlet</servlet-name>
        <url-pattern>*.action</url-pattern>
    </servlet-mapping>
</web-app>

4.5 测试程序

http://localhost:8080/user/findUserById.action?id=12