mybatis中的智能标签之二

Posted 2020-10-08 努力奋斗吧

智能标签foreach-Array， 智能标签foreach-List数据组，智能标签 foreach list自定义类型

接口：

/**
 * 智能标签foreach-Array
 * @param num
 * @return
 */
public List<Student> findByForeachArray(int[] num);

/**
 * 智能标签foreach-List
 * @param list
 * @return
 */
public List<Student> findByForeachList(List<Integer> list);


/**
 * 智能标签 foreach list自定义类型
 * @param list
 * @return
 */
public List<Student> findByForeachListStudent(List<Student> list);




xml文件（小配置）

<!--智能标签foreach-array-->
<select id="findByForeachArray" resultType="student">
    SELECT  *from Student
    <where>
       <if test="array.length>0">
           id in
           <foreach collection="array" open="(" close=")" separator="," item="id">
               #{id}
           </foreach>
       </if>
    </where>
</select>

<!--智能标签foreach-list数组-->
<select id="findByForeachList" resultType="student">
    SELECT  *from Student
    <where>
        <if test="list.size>0">
            id in
            <foreach collection="list" open="(" close=")" separator="," item="id">
                #{id}
            </foreach>
        </if>
    </where>
</select>

<!--智能标签foreach-list自定义类型-->
<select id="findByForeachListStudent" resultType="student">
    SELECT  *from Student
    <where>
        <if test="list.size>0">
            id in
            <foreach collection="list" open="(" close=")" separator="," item="it">
                #{it.id}
            </foreach>
        </if>
    </where>
</select>




测试类：

/**
 * 智能标签foreach-array
 */
@Test
public  void findByForeachArray(){
    SqlSession session = MyBatisUtil.getSession();
    IStudentDAO mapper = session.getMapper(IStudentDAO.class);
    int[] num={2,3,4};
    List<Student> list = mapper.findByForeachArray(num);
    for (Student item:list){
        System.out.println(item.getName());
    }
    session.commit();
    session.close();
}

/**
 * 智能标签foreach-list数组
 */
@Test
public  void findByForeachList(){
    SqlSession session = MyBatisUtil.getSession();
    IStudentDAO mapper = session.getMapper(IStudentDAO.class);
   List<Integer> list=new ArrayList<Integer>();
   list.add(2);
   list.add(9);
    List<Student> lists = mapper.findByForeachList(list);
    for (Student item:lists){
        System.out.println(item.getName());
    }
    session.commit();
    session.close();
}

/**
 * 智能标签foreach-list自定义类型
 */
@Test
public  void findByForeachListStudent(){
    SqlSession session = MyBatisUtil.getSession();
    IStudentDAO mapper = session.getMapper(IStudentDAO.class);
    List<Student> list=new ArrayList<Student>();
    Student student=new Student();
    student.setId(2);
    Student students=new Student();
    students.setId(9);
    list.add(student);
    list.add(students);
    List<Student> lists = mapper.findByForeachListStudent(list);
    for (Student item:lists){
        System.out.println(item.getName());
    }
    session.commit();
    session.close();
}