测试Hibernate添加查询修改删除学生信息（一对多的关系）

一 添加学生和班级测试代码

import com.imooc.util.HibernateUtil;

 

/*

 * 单向一对多关系关系（班级--->学生）

 * 建立关联关系后，可以方便的从一个对象导航到另一个对象

 * 注意关联的方向

 */

public class Test {

        public static void main(String[] args) {

                add();                

        }

        

        //将学生添加到班级

        public static void add(){

                Grade g=new Grade("Java一班", "Java软件开发一班");

                Student stu1=new Student("张三", "男");

                Student stu2=new Student("穆女神", "女");

                

                //如果希望在学生表中添加对应的班级编号，需要在班级中添加学生，建立关联关系

                g.getStudents().add(stu1);

                g.getStudents().add(stu2);

                

                Session session=HibernateUtil.getSession();

                Transaction tx=session.beginTransaction();

                session.save(g);

                session.save(stu1);

                session.save(stu2);

                tx.commit();

                HibernateUtil.closeSession(session);

        }

}

 

二 测试结果

Hibernate: select max(gid) from grade

Hibernate: select max(sid) from student

Hibernate: insert into grade (gname, gdesc, gid) values (?, ?, ?)

Hibernate: insert into student (sname, sex, sid) values (?, ?, ?)

Hibernate: insert into student (sname, sex, sid) values (?, ?, ?)

Hibernate: update student set gid=? where sid=?

Hibernate: update student set gid=? where sid=?

 

 

三 查询班级信息和班级中的学生信息测试代码

package com.imooc.test;

 

import java.util.Set;

 

import org.hibernate.Session;

import org.hibernate.Transaction;

 

import com.imooc.entity.Grade;

import com.imooc.entity.Student;

import com.imooc.util.HibernateUtil;

 

/*

 * 单向一对多关系关系（班级--->学生）

 * 建立关联关系后，可以方便的从一个对象导航到另一个对象

 * 注意关联的方向

 */

public class Test {

        public static void main(String[] args) {

                findStudentsByGrade();      

        }

        

        //查询班级中包含的学生

        public static void findStudentsByGrade(){

                Session session=HibernateUtil.getSession();

                Grade grade=(Grade) session.get(Grade.class, 1);

                System.out.println(grade.getGname()+","+grade.getGdesc());

                

                Set<Student> students=grade.getStudents();

                for(Student stu:students){

                        System.out.println(stu.getSname()+","+stu.getSex());

                }

        }

}

 

四 测试结果

Hibernate: select grade0_.gid as gid1_0_0_, grade0_.gname as gname2_0_0_, grade0_.gdesc as gdesc3_0_0_ from grade grade0_ where grade0_.gid=?

Java一班,Java软件开发一班

Hibernate: select students0_.gid as gid4_0_0_, students0_.sid as sid1_1_0_, students0_.sid as sid1_1_1_, students0_.sname as sname2_1_1_, students0_.sex as sex3_1_1_ from student students0_ where students0_.gid=?

穆女神,女

张三,男

 

五 修改学生信息测试代码

        //修改学生信息

        public static void update(){

                Grade g=new Grade("Java二班", "Java软件开发二班");

                

                Session session=HibernateUtil.getSession();

                Transaction tx=session.beginTransaction();

                Student stu=(Student) session.get(Student.class, 1);

                g.getStudents().add(stu);

                session.save(g);

                tx.commit();

                HibernateUtil.closeSession(session);

        }

 

六 测试结果

Hibernate: select student0_.sid as sid1_1_0_, student0_.sname as sname2_1_0_, student0_.sex as sex3_1_0_ from student student0_ where student0_.sid=?

Hibernate: select max(gid) from grade

Hibernate: insert into grade (gname, gdesc, gid) values (?, ?, ?)

Hibernate: update student set gid=? where sid=?

 

 

七 删除学生信息测试代码

        //删除学生信息

        public static void delete(){

                Session session=HibernateUtil.getSession();

                Transaction tx=session.beginTransaction();

                Student stu=(Student) session.get(Student.class, 2);

                session.delete(stu);

                tx.commit();

                HibernateUtil.closeSession(session);

        }

 

八 测试结果

Hibernate: select student0_.sid as sid1_1_0_, student0_.sname as sname2_1_0_, student0_.sex as sex3_1_0_ from student student0_ where student0_.sid=?

Hibernate: delete from student where sid=?