Mybatis基于配置文件注意事项

1.typeAlias   类型别名 

mybatisConfig.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>
<typeAliases>
<typeAlias alias="UserInfo" type="domain.model.UserInfo" />
<typeAlias alias="Bag" type="domain.model.Bag" />
</typeAliases>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC" />
<dataSource type="POOLED">
<property name="driver" value="com.microsoft.sqlserver.jdbc.SQLServerDriver" />
<property name="url" value="jdbc:sqlserver://localhost:1433;databasename=testMybatis" />
<property name="username" value="momo" />
<property name="password" value="momo" />
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="domain/config/UserMapper.xml" />
<mapper resource="domain/config/BagMapper.xml" />
</mappers>
</configuration>

userMapper.xml

<?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">
<mapper namespace="domain.mapper.UserMapper">
<select id="selectUserInfo" parameterType="int" resultType="UserInfo">
select * from UserInfo where id = #{id}
</select>

<insert id="save" parameterType="UserInfo">
insert into UserInfo(name) values(#{name})
</insert>

<select id="allCount" resultType="Int">
select count(*) from UserInfo
</select>

<select id="getUserInfoByName" parameterType="String" resultType="UserInfo">
select * from UserInfo where name =#{name}
</select>

<resultMap type="UserInfo" id="UserInfoResultMap">
<id column="ID" property="id" />
<result column="NAME" property="name"/>
</resultMap>

<select id="getUserInfoById" parameterType="Int" resultMap="UserInfoResultMap">
select * from UserInfo where id =#{id}
</select>

<select id="getUserByName" parameterType="String" resultType="UserInfo">
select * from UserInfo where NAME =#{name}
</select>
</mapper>

bagMapper.xml

<?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">
<mapper namespace="domain.mapper.BagMapper">
<resultMap type="Bag" id="bagResultMap">
<association property="user" select="getUserInfoById" column="userId" javaType="UserInfo"></association>
</resultMap><!--该user为bag对象中字段user-->

<select id="getBagByBagId" parameterType="Int" resultMap="bagResultMap">
select * from bag where id =#{id}
</select>
<select id="getUserInfoById" parameterType="Int" resultType="UserInfo">
select * from UserInfo where id =#{id}
</select>

</mapper>