test/target/SSM_03/WEB-INF/classes/mapper/treeMapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.itstudy.dao.TreeDao">
    <select id="findtrees" resultType="com.itstudy.domain.Trees">
        select  * from trees
    </select>
</mapper>