Spring/Spring MVC/MyBatis整合详解

本文引用自：《Java EE企业级应用开发教程》

由于Spring MVC只是Spring框架中的一个模块，所以Spring MVC与Spring之间不存在整合的问题，只需要引入相应Jar包就可以直接使用。因此，Spring/Spring MVC/MyBatis的整合，只涉及Spring与MyBatis的整合，以及Spring MVC与MyBatis的整合。

首先，定义三大框架的版本：

• Spring 5.2.3（注意：Spring框架的所有Jar包版本必须保持一致，否则会发生不可预料的错误！）
• Spring MVC 5.2.3
• MyBatis 3.5.2

其它附件的版本：

• log4j　　1.2.17
• mysql　　5.1.49
• mybatis-spring　　1.3.1

这些Jar包的引入地址，可以参考：https://mvnrepository.com/

一、准备所需要的Jar包

1.1 Spring核心包

    commons-logging-1.2.jar        Spring需要用它记录日志（第三方包）
    spring-beans-5.2.3.RELEASE.jar    SpringIoC（依赖注入）的基础实现
    spring-context-5.2.3.RELEASE.jar    Spring提供在基础IoC功能上的扩展服务，如邮件服务、任务调度、JNDI定位、EJB集成、远程访问、缓存以及各种视图层框架的封装等
    spring-core-5.2.3.RELEASE.jar        Spring核心包
    spring-expression-5.2.3.RELEASE.jar    Spring表达式语言
    spring-aop-5.2.3.RELEASE.jar        Spring的面向切面编程,提供AOP(面向切面编程)实现

1.2 Spring的JDBC相关包

    spring-jdbc-5.2.3.RELEASE.jar        JDBC驱动包
    spring-tx-5.2.3.RELEASE.jar        事务管理
    commons-dbcp2-2.1.1.jar        数据源所需
    commons-pool2-2.4.2.jar        数据源所需

1.3 Spring的aspectj相关包（可选 ，本节用不到）

    aopalliance-1.0.jar        AspectJ包（三个）
    aspectjrt-1.9.5.jar
    aspectjweaver-1.8.7.jar

1.4 Spring MVC相关包

    spring-webmvc-5.2.3.RELEASE.jar
    spring-web-5.2.3.RELEASE.jar

1.5 MyBatis相关包

    mybatis-3.5.2.jar
    ant-1.10.3.jar
    ant-launcher-1.10.3.jar
    asm-7.0.jar
    cglib-3.2.10.jar
    commons-logging-1.2.jar
    javassist-3.24.1-GA.jar
    log4j-1.2.17.jar
    log4j-api-2.11.2.jar
    log4j-core-2.11.2.jar
    ognl-3.2.10.jar
    slf4j-api-1.7.26.jar
    slf4j-log4j12-1.7.26.jar

1.6 其它包

mysql-connector-java-5.1.49-bin.jar    MySQL数据库驱动
mybatis-spring-1.3.1.jar        Spring与MyBatic整合包

1.7 pom.xml文件参考

<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>ssm</groupId>
    <artifactId>ssm</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>
    <name>ssm</name>
    <description />
    <properties>
        <webVersion>4.0</webVersion>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
    <dependencies>
        <dependency>
            <groupId>javax</groupId>
            <artifactId>javaee-api</artifactId>
            <version>8.0</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.glassfish.web</groupId>
            <artifactId>javax.servlet.jsp.jstl</artifactId>
            <version>1.2.4</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/log4j/log4j -->
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
        <!-- spring-context这个包囊括：spring-aop/spring-beans/spring-core/spring-expression -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.2.3.RELEASE</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework/spring-aop -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aop</artifactId>
            <version>5.2.17.RELEASE</version>
        </dependency>
        
        <!-- https://mvnrepository.com/artifact/org.aspectj/aspectjrt -->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjrt</artifactId>
            <version>1.8.7</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.aspectj/aspectjweaver -->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.8.7</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/aopalliance/aopalliance -->
        <dependency>
            <groupId>aopalliance</groupId>
            <artifactId>aopalliance</artifactId>
            <version>1.0</version>
        </dependency>
        
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-web -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>5.2.17.RELEASE</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.2.17.RELEASE</version>
        </dependency>        
        
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-jdbc -->
        <!-- spring-jdbc这个包囊括： spring-beans/spring-core/spring-tx -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.2.3.RELEASE</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
        <!-- mybatis这个包囊括： cglib (optional)/commons-logging (optional)
        /log4j (optional)/ognl (optional)/log4j-core (optional)
        /javassist (optional)/slf4j-api (optional)/slf4j-log4j12 (optional) -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        
        <!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.20</version>
            <scope>provided</scope>
        </dependency>

        <!-- https://mvnrepository.com/artifact/junit/junit -->
        <!-- junit这个包囊括： hamcrest-core -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13</version>
        </dependency>
        
        <!-- https://mvnrepository.com/artifact/org.apache.commons/commons-dbcp2 -->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-dbcp2</artifactId>
            <version>2.9.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.commons/commons-pool2 -->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-pool2</artifactId>
            <version>2.11.1</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.49</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.12.5</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.12.5</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-annotations -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.12.5</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/commons-fileupload/commons-fileupload -->
        <dependency>
            <groupId>commons-fileupload</groupId>
            <artifactId>commons-fileupload</artifactId>
            <version>1.3.3</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/commons-io/commons-io -->
        <dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>2.6</version>
        </dependency>
        
        <!-- https://mvnrepository.com/artifact/org.mybatis/mybatis-spring -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>1.3.3</version>
        </dependency>

        <dependency>
            <groupId>oraclejdbc</groupId>
            <artifactId>oraclejdbc</artifactId>
            <version>4.0</version>
            <scope>system</scope>
            <systemPath>${project.basedir}/lib/ojdbc6.jar</systemPath>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.3.2</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-war-plugin</artifactId>
                <version>3.2.3</version>
                <configuration>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>
        </plugins>
        <resources>
            <resource>
                <directory>lib</directory>
                <targetPath>/WEB-INF/lib/</targetPath>
                <includes>
                    <include>**/*.jar</include>
                </includes>
            </resource>
        </resources>
    </build>
</project>

注意：本配置文件额外引用lombok、junit、jackson、fileupload、oraclejdbc（本地引用）等相关包；不需要的，请自行删除。

二、创建配置文件

2.1 创建db.properties

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/xuejia?useUnicode=true&characterEncoding=UTF-8&serverTimezone=GMT%2B8
jdbc.username=root
jdbc.password=admin
jdbc.maxTotal=30
jdbc.maxIdle=10
jdbc.initialSize=5

2.2 创建log4j.properties

# Global logging configuration
log4j.rootLogger=ERROR, stdout
# MyBatis logging configuration...
log4j.logger.com.itheima=DEBUG
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

2.3 创建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:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans 
    http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
    http://www.springframework.org/schema/tx 
    http://www.springframework.org/schema/tx/spring-tx-4.3.xsd
    http://www.springframework.org/schema/context 
    http://www.springframework.org/schema/context/spring-context-4.3.xsd
    http://www.springframework.org/schema/aop 
    http://www.springframework.org/schema/aop/spring-aop-4.3.xsd">
    <!-- 读取db.properties -->
    <context:property-placeholder
        location="classpath:db.properties" />
    <!-- 配置数据源 -->
    <bean id="dataSource"
        class="org.apache.commons.dbcp2.BasicDataSource">
        <!--数据库驱动 -->
        <property name="driverClassName" value="${jdbc.driver}" />
        <!--连接数据库的url -->
        <property name="url" value="${jdbc.url}" />
        <!--连接数据库的用户名 -->
        <property name="username" value="${jdbc.username}" />
        <!--连接数据库的密码 -->
        <property name="password" value="${jdbc.password}" />
        <!--最大连接数 -->
        <property name="maxTotal" value="${jdbc.maxTotal}" />
        <!--最大空闲连接 -->
        <property name="maxIdle" value="${jdbc.maxIdle}" />
        <!--初始化连接数 -->
        <property name="initialSize" value="${jdbc.initialSize}" />
    </bean>
    <!-- 事务管理器，依赖于数据源 -->
    <bean id="transactionManager"
        class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource" />
    </bean>
    <!-- 开启事务注解 -->
    <tx:annotation-driven
        transaction-manager="transactionManager" />
    <!-- 配置MyBatis工厂SqlSessionFactory -->
    <bean id="sqlSessionFactory"
        class="org.mybatis.spring.SqlSessionFactoryBean">
        <!--注入数据源 -->
        <property name="dataSource" ref="dataSource" />
        <!--指定核MyBatis心配置文件位置 -->
        <property name="configLocation"
            value="classpath:mybatis-config.xml" />
    </bean>
    <!-- 配置mapper扫描器 -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.itheima.dao" />
    </bean>
    <!-- 扫描Service -->
    <context:component-scan
        base-package="com.itheima.service" />
</beans>

该文件中，首先根据db.properties的信息配置数据源；然后配置事务管理器并开启事务注解；接下来配置整合MyBatis框架的MyBatis工厂信息，最后定义mapper扫描器来扫描DAO层以及扫描Service层的配置。

2.4 创建mybatis-config.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>
    <!-- 别名定义 -->
    <typeAliases>
        <package name="com.itheima.po" />
    </typeAliases>
</configuration>

由于在Spring中已经配置数据源信息以及mapper接口文件扫描器，所以在MyBatis的配置文件中只需要根据POJO类路径进行别名配置即可。

2.5 创建springmvc-config.xml

<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"
  xmlns:tx="http://www.springframework.org/schema/tx"
  xsi:schemaLocation="http://www.springframework.org/schema/beans 
  http://www.springframework.org/schema/beans/spring-beans-4.3.xsd 
  http://www.springframework.org/schema/mvc 
  http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd 
  http://www.springframework.org/schema/context 
  http://www.springframework.org/schema/context/spring-context-4.3.xsd">
    <!-- 配置包扫描器，扫描@Controller注解的类 -->
    <context:component-scan base-package="com.itheima.controller" />
    <!-- 加载注解驱动 -->
    <mvc:annotation-driven />
    <!-- 配置视图解析器 -->
    <bean class=
    "org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/jsp/" />
        <property name="suffix" value=".jsp" />
    </bean>
</beans>

该文件中，主要配置用于扫描@Controller注解的包扫描器、注解驱动器以及视图解析器。

2.6 创建web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
      xmlns="http://xmlns.jcp.org/xml/ns/javaee" 
      xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee 
      http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" 
      id="WebApp_ID" version="3.1">
      <!-- 配置加载Spring文件的监听器-->
    <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>
    <!-- 编码过滤器 -->
    <filter>
        <filter-name>encoding</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>encoding</filter-name>
        <url-pattern>*.action</url-pattern>
    </filter-mapping>
    <!-- 配置Spring MVC前端核心控制器 -->
    <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:springmvc-config.xml</param-value>
        </init-param>
        <!-- 配置服务器启动后立即加载Spring MVC配置文件 -->
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <!--/:拦截所有请求（除了jsp）-->
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

该文件中，配置Spring的文件监听器、编码过滤器以及Spring MVC的前端控制器等信息。

三、创建各种程序

3.1 创建PO类 

package com.itheima.po;
/**
 * 客户持久化类
 */
public class Customer {
    private Integer id;       // 主键id
    private String username; // 客户名称
    private String jobs;      // 职业
    private String phone;     // 电话
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public String getJobs() {
        return jobs;
    }
    public void setJobs(String jobs) {
        this.jobs = jobs;
    }
    public String getPhone() {
        return phone;
    }
    public void setPhone(String phone) {
        this.phone = phone;
    }
}

此实体类对应的数据库SQL语句为：

CREATE TABLE `t_customer` (
  `ID` int(11) NOT NULL AUTO_INCREMENT,
  `USERNAME` varchar(45) NOT NULL,
  `JOBS` varchar(45) DEFAULT NULL,
  `PHONE` varchar(45) DEFAULT NULL,
  PRIMARY KEY (`ID`)
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8;

3.2 创建Dao类，及其对应的映射文件（同一个package）

CustomerDao.java

package com.itheima.dao;
import com.itheima.po.Customer;
/**
 * Customer接口文件
 */
public interface CustomerDao {
    /**
     * 根据id查询客户信息
     */
    public Customer findCustomerById(Integer id);
}

CustomerDao.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.itheima.dao.CustomerDao">
    <!--根据id查询客户信息 -->
    <select id="findCustomerById" parameterType="Integer"
                                       resultType="Customer">
        select * from t_customer where id = #{id}
    </select>
</mapper>

说明：配置文件applicationContext.xml，已经配置mapper扫描器扫描com.itheima.dao包下的所有接口及映射文件，所以此处完成DAO层接口及映射文件开发后，工作即告一段落。

3.3 创建service接口类，及其实现类

CustomerService.java

package com.itheima.service;
import com.itheima.po.Customer;
public interface CustomerService {
    public Customer findCustomerById(Integer id);
}

CustomerServiceImpl.java

package com.itheima.service.impl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import com.itheima.dao.CustomerDao;
import com.itheima.po.Customer;
import com.itheima.service.CustomerService;
@Service
@Transactional
public class CustomerServiceImpl implements CustomerService {
    //注解注入CustomerDao
    @Autowired
    private CustomerDao customerDao;
    //查询客户
    public Customer findCustomerById(Integer id) {
        return this.customerDao.findCustomerById(id);
    }
}

该文件中，使用@Service注解来标识业务层的实现类，使用@Transactional注解来标识类中所有方法都纳入Spring的事务管理，并使用@Autowired注解将CustomerDao对象注入到本类中，然后在本类的查询方法中调用CustomerDao对象的查询客户方法。

注：@Transactional注解主要针对数据的增加、修改、删除，此处仅为说明使用。

3.4 创建控制器类

package com.itheima.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import com.itheima.po.Customer;
import com.itheima.service.CustomerService;
@Controller
public class CustomerController {
    @Autowired
    private CustomerService customerService;
    /**
     * 根据id查询客户详情
     */
    @RequestMapping("/findCustomerById")
    public String findCustomerById(Integer id,Model model) {
        Customer customer = customerService.findCustomerById(id);
        model.addAttribute("customer", customer);
        //返回客户信息展示页面
        return "customer";
    }
}

该文件中，使用@Controller注解来标识控制器类，然后通过@Autowired注解将CustomerService接口对象注入到本类中，最后编写一个根据id查询客户的方法findCustomerById，并将结果返回到视图名为customer的JSP页面中。

3.5 创建JSP页面customer.jsp，位于：WEB-INF\jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>客户信息</title>
</head>
<body>
    <table border=1>
        <tr>
            <td>编号</td>
            <td>名称</td>
            <td>职业</td>
            <td>电话</td>
        </tr>
        <tr>
            <td>${customer.id}</td>
            <td>${customer.username}</td>
            <td>${customer.jobs}</td>
            <td>${customer.phone}</td>
        </tr>
    </table>
</body>
</html>

四、测试，打开页面：http://localhost:8080/ssm/findCustomerById?id=1

结果如上图所示。