详解Mybatis（五）Mapper接口

<?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">
<!-- 为这个mapper指定一个唯一的namespace，namespace的值习惯上设置成包名+sql映射文件名，这样就能够保证namespace的值是唯一的
例如namespace="me.gacl.mapping.userMapper"就是me.gacl.mapping(包名)+userMapper(userMapper.xml文件去除后缀)
 -->
<mapper namespace="Mybatis.domain.Mapper.UserMapper">

  <resultMap type="User" id="BaseResultMap">
  	<result column="t_id" property="id"/>
  	<result column="t_name" property="name"/>
  	<result column="t_salary" property="salary"/>
  </resultMap>
  
  <!-- 保存操作 -->
  <insert id="save" useGeneratedKeys="true" keyProperty="id">
	  INSERT INTO t_user (name , salary) 	VALUES (#{name},#{salary}) 	
  </insert>
  
  <!-- 更改操作 -->
  <update id="update">
  	update t_user where name=#{name},salary=#{salary} where id=#{id}
  </update>
  
  <!-- 删除操作 -->
  <delete id="delete" >
  	delete from t_user where id=#{id}
  </delete>
  
  <!-- 查询单个操作 --> 
  <select id="select" parameterMap="java.lang.Long" resultType="Mybatis.domain.User">
    select * from t_user where id = #{id}
  </select>

	<!-- 查询多个操作 -->
	<select id="selectAll" resultType="User">
		select id,name,salary from t_user
	</select>  
</mapper>

import java.util.List;

import Mybatis.domain.User;

public interface UserMapper {
	void save(User u);
	
	void update(User u);
	
	void delete(Long id);
	
	User select(User u);
	
	List<User> selectAll();
}