spring整合mybatis

项目结构：

表：

create table user(
  username varchar(50),
  pswd varchar(50),
  sex varchar(50)
);

表中的数据：

自定义注释：

Type_User_Annotation:

/*User类对应User表的注解*/
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
public @interface Type_User_Annotation {
    String value(); //表名
}

Field_User_Annotaion:

@Target(ElementType.FIELD)
@Retention(RetentionPolicy.RUNTIME)
public @interface Field_User_Annotation { //表对应实体类属性的注释
    String columnName(); //列名
    String type(); //类型
    int length(); //长度
}

UserMapper接口：

public interface UserMapper {
    @Select("select * from User WHERE username = #{username}")
    public User getUserByUsername(@Param("username")String username);
}

UserMapperImpl实现类：

public class UserMapperImpl implements UserMapper{
    private SqlSessionTemplate sqlSessionTemplate;
    public void setSqlSessionTemplate(SqlSessionTemplate sqlSessionTemplate){
        this.sqlSessionTemplate = sqlSessionTemplate;
    }
    @Override
    public User getUserByUsername(String username) {
        UserMapper mapper = sqlSessionTemplate.getMapper(UserMapper.class);
        return mapper.getUserByUsername("晓晓");
    }
}

实体类User：

@Data
@AllArgsConstructor
@NoArgsConstructor
@ToString
@Type_User_Annotation("User")
public class User {
    @Field_User_Annotation(columnName = "username",type = "varchar",length = 50)
    private String username;
    @Field_User_Annotation(columnName = "pswd",type = "varchar",length = 50)
    private String pswd;
    @Field_User_Annotation(columnName = "sex",type = "varchar",length = 50)
    private String sex;
}

UserMapper.xml：

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="dao.UserMapper">
    <cache/>

</mapper>

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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/aop
       http://www.springframework.org/schema/aop/spring-aop.xsd">
       <import resource="spring-dao.xml"/>
       <bean id="userMapperImpl" class="dao.UserMapperImpl">
              <property name="sqlSessionTemplate" ref="sqlSessionTemplate"/>
       </bean>
</beans>

log4j.properties：

#将等级为DEBUG的日志信息输出到console和file这两个目的地，console和file的定义在下面的代码
log4j.rootLogger=DEBUG,console,file

#控制台输出的相关设置
log4j.appender.console = org.apache.log4j.ConsoleAppender
log4j.appender.console.Target = System.out
log4j.appender.console.Threshold=DEBUG
log4j.appender.console.layout = org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=[%c]-%m%n

#文件输出的相关设置
log4j.appender.file = org.apache.log4j.RollingFileAppender
log4j.appender.file.File=./log/ming.log
log4j.appender.file.MaxFileSize=10mb
log4j.appender.file.Threshold=DEBUG
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=[%p][%d{yy-MM-dd}][%c]%m%n

#日志输出级别
log4j.logger.org.mybatis=DEBUG
log4j.logger.java.sql=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.ResultSet=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG

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>
    <settings>
        <setting name="logImpl" value="LOG4J"/>
        <setting name="cacheEnabled" value="true"/>
    </settings>
    <typeAliases>
        <package name="pojo"/>
        <package name="dao"/>
    </typeAliases>
</configuration>

spring-dao.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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/aop
       http://www.springframework.org/schema/aop/spring-aop.xsd">
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF-8&amp;serverTimezone=GMT%2B8"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>
    </bean>
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath:dao/*.xml"/>
    </bean>
    <bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg index="0" ref="sqlSessionFactory"/>
    </bean>
</beans>

控制台输出：

第二种整合方式（常用）：

改变UserMapperImpl实现类：

public class UserMapperImpl2 extends SqlSessionDaoSupport implements UserMapper {
    @Override
    public User getUserByUsername(String username) {
        return this.getSqlSession().getMapper(UserMapper.class).getUserByUsername("晓晓");
    }
}

删掉spring-dao.xml中不必要的配置：

<?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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/aop
       http://www.springframework.org/schema/aop/spring-aop.xsd">
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF-8&amp;serverTimezone=GMT%2B8"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>
    </bean>
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath:dao/*.xml"/>
    </bean>
</beans>

ApplicationContext写法：

<?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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/aop
       http://www.springframework.org/schema/aop/spring-aop.xsd">
       <import resource="spring-dao.xml"/>
       <bean id="userMapperImpl2" class="dao.UserMapperImpl2">
              <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
       </bean>
</beans>