Mybatis-sql语句的抽取

1.抽取之前的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="com.hao.mapper.UserMapper">
<select id="findByCondition" parameterType="user" resultType="user">
select * from user
<where>
<if test="id!=0">
and id=#{id}
</if>
<if test="username!=null">
and username=#{username}
</if>
<if test="password!=null">
and password=#{password}
</if>
</where>
</select>
<select id="findByIds" parameterType="list" resultType="user">
select * from user
<where>
<foreach collection="list" open="id in(" close=")" item="id" separator=",">
#{id}
</foreach>
</where>
</select>
</mapper>

2.抽取之后的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="com.hao.mapper.UserMapper">
<!-- sql语句的抽取-->
<sql id="selectUser">select * from user</sql>
<select id="findByCondition" parameterType="user" resultType="user">
<include refid="selectUser"></include>
<where>
<if test="id!=0">
and id=#{id}
</if>
<if test="username!=null">
and username=#{username}
</if>
<if test="password!=null">
and password=#{password}
</if>
</where>
</select>
<select id="findByIds" parameterType="list" resultType="user">
<include refid="selectUser"></include>
<where>
<foreach collection="list" open="id in(" close=")" item="id" separator=",">
#{id}
</foreach>
</where>
</select>
</mapper>

refid：引用