Mybatis入门（三）
数据库
public class Student {
private String sno;
public String getSno() {
return sno;
}
public void setSno(String sno) {
this.sno = sno;
}
public String getsName() {
return sName;
}
public void setsName(String sName) {
this.sName = sName;
}
public String getsSex() {
return sSex;
}
public void setsSex(String sSex) {
this.sSex = sSex;
}
public String getsAge() {
return sAge;
}
public void setsAge(String sAge) {
this.sAge = sAge;
}
public String getsDept() {
return sDept;
}
public void setsDept(String sDept) {
this.sDept = sDept;
}
public String sName;
public String sSex;
public String sAge;
public String sDept;
public String getcId() {
return cId;
}
public void setcId(String cId) {
this.cId = cId;
}
private String cId;
public Student(String sno, String sName, String sSex, String sAge,
String sDept,String cId) {
super();
this.sno = sno;
this.sName = sName;
this.sSex = sSex;
this.sAge = sAge;
this.sDept = sDept;
this.cId=cId;
}
public Student() {
super();
}
@Override
public String toString() {
return "Student [sno=" + sno + ", sName=" + sName + ", sSex=" + sSex
+ ", sAge=" + sAge + ", sDept=" + sDept + ", cId=" + cId + "]";
}
}
public class Classes {
private String cId;
public String getcId() {
return cId;
}
public void setcId(String cId) {
this.cId = cId;
}
public String getcName() {
return cName;
}
public void setcName(String cName) {
this.cName = cName;
}
private String cName;
public Classes(String cId, String cName) {
super();
this.cId = cId;
this.cName = cName;
}
public Classes() {
super();
}
@Override
public String toString() {
return "Classes [cId=" + cId + ", cName=" + cName + "]";
}
}
public class Teacher {
private String tId;
public String gettId() {
return tId;
}
public void settId(String tId) {
this.tId = tId;
}
public String gettName() {
return tName;
}
public void settName(String tName) {
this.tName = tName;
}
private String tName;
public Teacher(String tId, String tName) {
super();
this.tId = tId;
this.tName = tName;
}
public Teacher() {
super();
}
@Override
public String toString() {
return "Teacher [tId=" + tId + ", tName=" + tName + "]";
}
}
实例（一）
查询每个班级及其老师的详细信息。
1.创建ClassTeacher.java
public class ClassTeacher {
private Classes classes;
private List<Teacher> teaList;
public Classes getClasses() {
return classes;
}
public void setClasses(Classes classes) {
this.classes = classes;
}
public List<Teacher> getTeaList() {
return teaList;
}
public void setTeaList(List<Teacher> teaList) {
this.teaList = teaList;
}
public ClassTeacher( Classes classes, List<Teacher> teaList) {
super();
this.classes = classes;
this.teaList = teaList;
}
public ClassTeacher() {
super();
}
@Override
public String toString() {
return "ClassTeacher [ classes=" + classes + ", teaList="
+ teaList + "]";
}
}
2.创建classTeacherMapping.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.bean.classTeacherMapping">
<select id="getClassTeachInfor" resultMap="getClassTeaches">
select * from teacher s,classes c,teaches t where s.t_id =t.t_id and c.c_id=t.c_id;
</select>
<resultMap type="com.bean.ClassTeacher" id="getClassTeaches">
<id column="c_id"/>
<association property="classes" javaType="com.bean.Classes">
<id property="cId" column="c_id"/>
<result property="cName" column="c_name"/>
</association>
<collection property="teaList" ofType="com.bean.Teacher">
<id property="tId" column="t_id"/>
<result property="tName" column="t_name"/>
</collection>
</resultMap>
</mapper>
3.查询结果。
String classTeacherMap="com.bean.classTeacherMapping";
String classTeacherSelect=classTeacherMap+".getClassTeachInfor";
List<ClassTeacher> ctList=sqlSession.selectList(classTeacherSelect);
System.out.println(ctList);