Mybatis中Collection集合标签的使用详解

import java.util.List;

public class ClazzEntity {

  private int clazzID;

  private String clazzName;

  private List<StudentEntity> studentList;

  public int getClassID() {
    return clazzID;
  }

  public int getClazzID() {
    return clazzID;
  }

  public void setClazzID(int clazzID) {
    this.clazzID = clazzID;
  }

  public String getClazzName() {
    return clazzName;
  }

  public void setClazzName(String clazzName) {
    this.clazzName = clazzName;
  }

  public List<StudentEntity> getStudentList() {
    return studentList;
  }

  public void setStudentList(List<StudentEntity> studentList) {
    this.studentList = studentList;
  }
}

package com.cn.hnust.pojo;

public class StudentEntity {

  private int stuID;

  private String stuName;

  private int stuAge;

  private String stuAddress;

  public int getStuID() {
    return stuID;
  }

  public void setStuID(int stuID) {
    this.stuID = stuID;
  }

  public String getStuName() {
    return stuName;
  }

  public void setStuName(String stuName) {
    this.stuName = stuName;
  }

  public int getStuAge() {
    return stuAge;
  }

  public void setStuAge(int stuAge) {
    this.stuAge = stuAge;
  }

  public String getStuAddress() {
    return stuAddress;
  }

  public void setStuAddress(String stuAddress) {
    this.stuAddress = stuAddress;
  }
}

CREATE TABLE student_t
(
stuno INT PRIMARY KEY,
stuname VARCHAR(20),
stuage INT,
stuaddress VARCHAR(20) ,
classid INT
);
CREATE TABLE class_t
(
classid INT PRIMARY KEY,
classname VARCHAR(20)
);

<?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.cn.hnust.dao.InfoManageDao" >

 <resultMap id="ClazzResultMap" type="com.cn.hnust.pojo.ClazzEntity" >
  <id column="classID" property="clazzID" jdbcType="INTEGER" />
  <result column="className" property="clazzName" jdbcType="VARCHAR" />
  <collection property="studentList" column="classID" javaType="ArrayList" 
        ofType="com.cn.hnust.pojo.StudentEntity" select="getStudentByClassID"/>
 </resultMap>

 <resultMap id="StudentResultMap" type="com.cn.hnust.pojo.StudentEntity"> 
  <id property="stuID" column="stuID" /> 
  <result property="stuName" column="stuName" /> 
  <result property="stuAge" column="stuAge" /> 
  <result property="stuAddress" column="stuAddress" />
 </resultMap> 

<select id="getClassByID" resultMap="ClazzResultMap" parameterType="java.lang.Integer" >
  select classID,className
  from class_t
  where classID = #{clazzID}
</select>

<select id="getStudentByClassID" resultMap="StudentResultMap" parameterType="java.lang.Integer" >
  select stuID,stuName,stuAge,stuAddress,classID
  from student_t
  where classID = #{clazzID}
</select>

</mapper>