one2manytest.java

hibernate一对多双向关联映射 一对多双向关联映射的方法 在"一"一端的集合中使用<key>标签,在对方表中加入一个外键指向"一"端 在"多"的一端采用<ma

package com.xt.hibernate;

import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

import junit.framework.TestCase;

import org.hibernate.Session;

import com.xt.hibernate.utils.hibernateUtils;

public class one2manyTest extends TestCase {
	public void testone2many(){
		Session session = null;
		try{
			session = hibernateUtils.getSession();
			session.beginTransaction();
			
			Student stu1 = new Student();
			stu1.setName("张飞");
			session.save(stu1);
			Student stu2 = new Student();
			stu2.setName("刘备");
			session.save(stu2);
			
			Set student = new HashSet();
			student.add(stu1);
			student.add(stu2);
			
			Classes classes = new Classes();
			classes.setName("讯腾国际");
			classes.setStudent(student);
			
			session.save(classes);
			
			session.getTransaction().commit();
		}catch(Exception e){
			e.printStackTrace();
			session.getTransaction().rollback();
		}finally{
			hibernateUtils.closeSession(session);
		}
	}
	
	public void testLoadone2many(){
		Session session = null;
		try{
			session = hibernateUtils.getSession();
			session.beginTransaction();
			
			Classes classes = (Classes)session.load(Classes.class, new Integer(2));
			System.out.println("name:"+classes.getName());
			Set student = classes.getStudent();
			for(Iterator it = student.iterator();it.hasNext();){
				Student stu = (Student)it.next();
				System.out.println("stu:"+stu.getName());
			}
			
			
			session.getTransaction().commit();
		}catch(Exception e){
			e.printStackTrace();
			session.getTransaction().rollback();
		}finally{
			hibernateUtils.closeSession(session);
		}
	}
	
}