Spring与MyBatis整合上_Mapper动态代理方式

     将MyBatis与Spring进行整合，主要解决的问题就是将SqlSessionFactory对象交由Spring来管理。。所以该整合，只需将SQLSessionFactory的对象生成器SQLSessionFactoryBean注册到Spring容器中，再将其注入给Dao的实现类即可完成整合。

可以通过2种方式来实现Spring与MyBatis的整合：

• Mapper动态代理
• 支持扫描的Mapper动态代理

一、环境搭建

二、定义映射文件

 import java.util.List;

 import com.jmu.beans.Student;

 //Dao增删改查
 public interface IStudentDao {
     void insertStudent(Student student);
     void deleteById(int id);
     void updateStudent(Student student);

     List<String> selectAllStudentsNames();
     String selectStudentNameById(int id);

     List<Student> selectAllStudents();
     Student selectStudentById(int id);
 }

IStudentDao

 <?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.jmu.dao.IStudentDao">
     <insert id="insertStudent">
         insert into student(name,age) values(#{name},#{age})
     </insert>

     <delete id="deleteById">
         delete from student where id=#{XXX}
     </delete>

     <update id="updateStudent">
         update student set name=#{name},age=#{age} where id=#{id}
     </update>

     <select id="selectAllStudents" resultType="student">
         select id,name,age from student
     </select>

     <select id="selectStudentById" resultType="student">
         select id,name,age from student where id=#{XXX}
     </select>
 </mapper>

mapper.xml

三、定义主配置文件

 <?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>

     <!--配置别名 -->
     <typeAliases>
         <package name="com.jmu.beans" />
     </typeAliases>

     <mappers>
         <!-- <mapper resource="com/jmu/dao/mapper.xml"/> -->
         <!--xml文件和dao同名 -->
         <package name="com.jmu.dao" />

     </mappers>

 </configuration>

mybatis.xml

四、Mapper动态代理方式生成Dao代理对象

 <?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">

     <!--注册数据源:C3P0 -->
     <bean id="myDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
         <property name="driverClass" value="${jdbc.driver}" />
         <property name="jdbcUrl" value="${jdbc.url}" />
         <property name="user" value="${jdbc.user}" />
         <property name="password" value="${jdbc.password}" />
     </bean>

     <!-- 注册属性文件 -->
     <context:property-placeholder location="classpath:jdbc.properties" />

     <bean id="mySqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="configLocation" value="classpath:mybatis.xml"></property>
        <property name="dataSource" ref="myDataSource"></property>
     </bean>

     <!--生成Dao的代理对象 -->
     <bean id="studentDao" class="org.mybatis.spring.mapper.MapperFactoryBean">
         <property name="sqlSessionFactory" ref="mySqlSessionFactory" />
         <property name="mapperInterface" value="com.jmu.dao.IStudentDao" />
     </bean>

     <!-- 注册Service -->
     <bean id="studentService" class="com.jmu.service.StudentServiceImpl">
         <property name="dao" ref="studentDao" />
     </bean>
 </beans>

applicationContext.xml

五、测试

 import java.util.List;

 import org.junit.Before;
 import org.junit.Test;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.support.ClassPathXmlApplicationContext;

 import com.jmu.beans.Student;
 import com.jmu.service.IStudentService;

 public class MyTest {

     private IStudentService service;

     @Before
     public void before() {
         //创建容器对象
         String resource = "applicationContext.xml";
         ApplicationContext ac=new ClassPathXmlApplicationContext(resource);
         service = (IStudentService) ac.getBean("studentService");
     }

     @Test
     public void test01() {
         Student student=new Student("张三", 23);
         service.addStudent(student);
     }

     @Test
     public void test02() {
         service.removeById(2);
     }

     @Test
     public void test03() {
         Student student=new Student("王意义", 23);
         student.setId(3);
         service.modifyStudent(student);
     }
     @Test
     public void test04() {
         List<String> names = service.findAllStudentsNames();
         System.out.println(names);
     }
     @Test
     public void test05() {
         String names = service.findStudentNameById(3);
         System.out.println(names);
     }

     @Test
     public void test06() {
         List<Student> students=service.findAllStudents();
         for (Student student : students) {
             System.out.println(student);
         }
     }

     @Test
     public void test07() {
         Student student=service.findStudentById(3);
         System.out.println(student);
     }

 }

MyTest

对于IstudentDao.xml中没有写到的List<String> selectAllStudentsNames()和String selectStudentNameById(int id)进行修改

六、支持扫描的动态代理

对于上面的情况，如果有多个Dao接口，就要写多次的以下字段

<!--生成Dao的代理对象 -->
    <bean id="studentDao" class="org.mybatis.spring.mapper.MapperFactoryBean">
        <property name="sqlSessionFactory" ref="mySqlSessionFactory" />
        <property name="mapperInterface" value="com.jmu.dao.IStudentDao" />
    </bean>

 <!--生成Dao的代理对象
      当前配置会被本包中所有的接口生成代理对象
     -->
     <bean  class="org.mybatis.spring.mapper.MapperScannerConfigurer">
         <property name="sqlSessionFactoryBeanName" value="mySqlSessionFactory" />
         <property name="basePackage" value="com.jmu.dao" />
     </bean>

     <!-- 注册Service -->
     <bean id="studentService" class="com.jmu.service.StudentServiceImpl">
          <!-- 这里的Dao的注入需要使用ref属性，且其作为接口的简单类名 -->
         <property name="dao" ref="studentDao" />
     </bean>

applicationContext

---