mybatis：choose标签

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mapping

<?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.java1234.mappers.StudentMapper">

	<resultMap type="Student" id="StudentResult">
		<id property="id" column="id"/>
		<result property="name" column="name"/>
		<result property="age" column="age"/>
	</resultMap>
	
	<select id="searchStudents" parameterType="Map" resultMap="StudentResult">
		select * from t_student 
		 where gradeId=#{gradeId}
		 <if test="name!=null">
		 	and name like #{name}
		 </if>
		 <if test="age!=nulll">
		 	and age=#{age}
		 </if>
	</select>
	
	<select id="searchStudents2" parameterType="Map" resultMap="StudentResult">
		select * from t_student 
		 <choose>
		 	<when test="searchBy=='gradeId'">
		 		where gradeId=#{gradeId}
		 	</when>
		 	<when test="searchBy=='name'">
		 		where name like #{name}
		 	</when>
		 	<otherwise>
		 		where age=#{age}
		 	</otherwise>
		 </choose>	 
	</select>
    
</mapper> 

调用测试

@Test
public void testSearchStudents() {
    logger.info("添加学生(带条件)");
    Map<String,Object> map=new HashMap<String,Object>();
    map.put("gradeId", 2);
    // map.put("name", "%李%");
    // map.put("age", 11);
    List<Student> studentList=studentMapper.searchStudents(map);
    for(Student student:studentList){
        System.out.println(student);
    }
}

@Test
public void testSearchStudents2() {
    logger.info("添加学生(带条件)");
    Map<String,Object> map=new HashMap<String,Object>();
    map.put("searchBy", "age");
    map.put("gradeId", 2);
    map.put("name", "%李%");
    map.put("age", 11);
    List<Student> studentList=studentMapper.searchStudents2(map);
    for(Student student:studentList){
        System.out.println(student);
    }
}