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Mapper files

Use @RefMapper instead of @SimpleMapper to link a mapper interface to an XML file and map some or all methods to that file.

1. Link mapper interface to XML via @RefMapper
@RefMapper("/mapper/userMapper.xml")
public interface UserMapper {
    // Declarative API
    @Insert({ "insert into users (",
            "    id, name, age, create_time",
            ") values (",
            "    #{id}, #{name}, #{age}, #{createTime})",
            ")" })
    int saveUser(User user);

    // Map query to XML for more complex logic
    List<User> listUsers(@Param("searchId") long searchId, List<String> prefixList);
}
2. Define some or all mapper methods in XML
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//dbvisitor.net//DTD Mapper 1.0//EN"
        "https://www.dbvisitor.net/schema/dbvisitor-mapper.dtd">
    <!-- ➊ namespace matches the mapper interface name -->
<mapper namespace="net.example.mapper.UserMapper">
    <!-- ➋ select id matches the method name; result type comes from the interface method -->
    <select id="listUsers">
        select <include refid="userColumns"/>
        from   users
        where  owner_uid = #{searchId} and
               <if test="prefixList != null and prefixList.size() > 0">
                   <foreach collection="prefixList" item="item" index="index" separator="or" open="and (" close=")">
                       #{item} like concat(res_path,'%')
                   </foreach>
               </if>
    </select>
</mapper>
3. Create and use the mapper
// 1) Create Configuration
Configuration config = new Configuration();

// 2) Create Session
Session session = config.newSession(dataSource);
或者
Session session = config.newSession(connection);

// 3) Create mapper
UserMapper mapper = session.createMapper(UserMapper.class);
List<User> result = mapper.listUsers(2, prefixList);

Quick guide​