Spring+JdbcTemplate+mybatis

Spring+JdbcTemplate

1.dao组件继承org.springframework.jdbc.core.support.JdbcDaoSupport
applicationContext.xml文件中配置

    id = "jdbcProperties" location = "classpath:db.properties">

    id = "myDataSource2" class = "org.apache.commons.dbcp.BasicDataSource" destroy-method = "close">
        <property name="driverClassName" value ="#{jdbcProperties.driver}">property>
        <property name="url" value="#{jdbcProperties.url}">property>
        <property name="username" value="#{jdbcProperties.user}">property>
        <property name="password" value="#{jdbcProperties.pwd}">property>
    

    id = "empDao01" class = "hateapple.dao.EmpDao01">
        <property name="dataSource" ref = "myDataSource2">property>
    

empDao01通过setter注入dataSource，set方法继承自JdbcDaoSupport,且不能被覆盖重写

//set方法签名
public final void setDataSource(DataSource dataSource)

其实就是注入的dataSource被父类JdbcDaoSupport拿去初始化自己的成员变量jdbcTemplate了，empDao01想要使用jdbcTemplate只能通过getJdbcTemplate。

2.不继承
org.springframework.jdbc.core.support.JdbcDaoSupport,为empDao02注入jdbcTemplate，empDao02通过jdbcTemplate操作数据库；
applicationContext.xml文件配置

    id = "myDataSource" class = "org.apache.commons.dbcp.BasicDataSource" destroy-method = "close">
        <property name="driverClassName" value ="oracle.jdbc.driver.OracleDriver">property>
        <property name="url" value="jdbc:oracle:thin:@localhost:1521:orcl">property>
        <property name="username" value="em">property>
        <property name="password" value="em">property>
    

    id = "jdbcTemplate" class = "org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref = "myDataSource">property>
    
    id = "empDao02" class = "hateapple.dao.EmpDao02">
        <property name="jdbcTemplate" ref = "jdbcTemplate">property>
    

对比两种方式，第一种是把钥匙交给门卫用的时候向门卫拿，第二种自己带身上。

Spring+myBatis

1.spring整合mybatis 的核心是 SqlSessionFactoryBean、MapperFactoryBean(单一接口)

org.mybatis.spring.SqlSessionFactoryBean包含了dataSource(数据源)、mapperLocations(接口的mapper映射文件路径);

org.mybatis.spring.mapper.MapperFactoryBean包含了sqlSessionFactory(上面的bean),mapperInterface(接口的完整名称);

<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref = "myDataSource">property>
        
        <property name="mapperLocations" value = "classpath:hateapple/mapper/StudentMapperMyBatis.xml">property>
bean>


<bean id="studentMapper" class= "org.mybatis.spring.mapper.MapperFactoryBean">
        <property name="mapperInterface" value="hateapple.dao.BaseDao">property>
        <property name="sqlSessionFactory" ref ="sqlSessionFactory">property>
bean>

测试代码

        @Test
        public void testMybatis(){
            String conf = "applicationContext.xml";
            ClassPathXmlApplicationContext ac = new ClassPathXmlApplicationContext(conf);
            BaseDao baseDao = (BaseDao)ac.getBean("studentMapper");
            List studentList = baseDao.findAll();
            for (Student  student : studentList) {
                System.out.println(student.getName());
            }

如果需要多个org.mybatis.spring.mapper.MapperFactoryBean，一个一个配置肯定不现实

2. MapperScannerConfigurer批量扫描接口，并为每个接口生成一个 MapperFactoryBean的实例

<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        
        <property name="basePackage" value ="hateapple.dao">property>
        
        <property name="sqlSessionFactory" ref ="sqlSessionFactory">property>
        
        <property name="annotationClass" value="hateapple.annotation.MyMapperAnnotation">property>
bean>

MyMapperAnnotation .java

public @interface MyMapperAnnotation {

}

BaseDao.java

@MyMapperAnnotation
public interface BaseDao {
    public List findAll();
}

测试代码:

        @Test
        public void testMybatis(){
            String conf = "applicationContext.xml";
            ClassPathXmlApplicationContext ac = new ClassPathXmlApplicationContext(conf);
            BaseDao baseDao = (BaseDao)ac.getBean("baseDao");
            List studentList = baseDao.findAll();
            for (Student  student : studentList) {
                System.out.println(student.getName());
            }

spring+SqlSessionTemplate

其实org.mybatis.spring.mapper.MapperFactoryBean就是封装了一个SqlSessionTemplate操作数据库，我们调用baseDao.findAll()最终的操作还是sqlSessionTemplate.selectList(“findAll”)

1.直接为操作数据库类注入sqlSessionTemplate

id ="sqlSessionTemplate" class = "org.mybatis.spring.SqlSessionTemplate">
        "0" ref="sqlSessionFactory">

    //sqlSessionTemplate是被注入进来的
    @Override
    public List findAll() {
        List studentList = sqlSessionTemplate.selectList("findAll");
        for (Student student : studentList) {
            System.out.println(student.getName());
        }
        return studentList;
    }