spring整合mybatis时,要使用mybatis的注解,需要spring-config.xml文件中添加下述配置:
<!--下述配置指明了我们的Mapper,即Dao,在相应的包里也就可以使用注解了,同时不用写Dao的实现类了 -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.itszt.dao"></property>
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>
</bean>
UserDao.xml文件配置如下:
<?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">
<!--
保证命名空间,和接口的全类名一致
-->
<mapper namespace="com.itszt.dao.UserDao">
<resultMap id="userMap" type="user">
<id property="uid" column="uid"></id>
<result property="username111" column="username"></result>
</resultMap>
</mapper>
此时,在与UserDao.xml文件同一包下的UserDao接口可以直接写sql操作语句:
package com.itszt.dao;
import com.itszt.domain.User;
import com.itszt.domain.User2;
import org.apache.ibatis.annotations.*;
import org.springframework.stereotype.Repository;
import java.util.List;
/**
* 我们给接口加@Repository注解,会根据我们的MapperScanner配置,
*将来会自动为该接口构建匿名实现类,然后实例化这个实现类的对象拿去使用
* 而实现类的具体方法功能怎么实现,由两方面决定:
* 1.UserDao.xml 2.interface UserDao中的注解
*/
@Repository
public interface UserDao {
//演示常用查询
@Select("select * from user where uid=#{uid}")
public User findUserByUID(int uid); @Select("select * from user where username=#{username} and userage=#{userage}")
public User findUserByNameAndAge(@Param("username") String username, @Param("userage")int age); @Select("select count(*) from user")
public Integer queryUserCount(); //演示insert ,并且获取自动递增的id赋值
@Insert("insert into user(username,userage,usersalary,regTime) values(#{username},#{userage},#{usersalary},#{regTime})")
@SelectKey(keyProperty = "uid",keyColumn = "uid",resultType = Integer.class,before = false,statement = "select last_insert_id()")
public void testaddUser1(User user); //演示insert ,并且获取自动设置UUID
@Insert("insert into user2(uid,username,userage,usersalary,regTime) values(#{uid},#{username},#{userage},#{usersalary},#{regTime})")
@SelectKey(keyProperty = "uid",keyColumn = "uid",resultType = String.class,before = true,statement = "select uuid()")
public void testaddUser2(User2 user); //演示删除
@Delete("delete from user where uid=#{uid}")
public void testDeleteUser(int uid);
//演示更新某个字段
@Update("update user set username=#{username} where uid=#{uid}")
public void testUpdateUser1(@Param("uid") int uid,@Param("username")String username); //演示ResultMap
@Select("select * from user where uid=#{uid}")
// @ResultMap("userMap")
@Results({@Result(property = "username111",column = "username")})
public User testReusltRM(int uid); //演示list
@Select("<script>" +
"SELECT * FROM user WHERE uid IN\n" +
"<foreach collection=\"list\" open=\"(\" close=\")\" separator=\",\" item=\"uid\">\n" +
" #{uid}\n" +
"</foreach>"+
"</script>")
public List<User> findUsersByIDs(List<Integer> uids); //演示list2,基于自定义SQL来做
@Select("SELECT * FROM user WHERE uid IN list:#{uids}")
@Lang(SelectInLangDriver.class)
public List<User> findUsersByIDs3(@Param("uids") List<Integer> uids); //演示list3,基于自定义SQL来做,能够支持多个集合
@Select("SELECT * FROM user WHERE uid IN list:#{uids} or userage IN list:#{ages}")
@Lang(SelectInLangDriver2.class)
public List<User> findUsersByIDs4(@Param("uids") List<Integer> uids,@Param("ages") List<Integer> ages);
}