<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC"-//Hibernate/Hibernate Mapping DTD 3.0//EN""http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><hibernate-mapping package="cn.happy.entity"><class name="Dept" table="DEPT"><id name="deptNo"><generator class="sequence"><param name="sqeuence">SEQ_NUM</param></generator></id><set name="emps"><key column="DEPTNO"></key><one-to-many class="Emp"></one-to-many></set><property name="deptName">  </property></class></hibernate-mapping>

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC"-//Hibernate/Hibernate Mapping DTD 3.0//EN""http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><hibernate-mapping package="cn.happy.entity"><class name="Emp" table="EMP"><id name="empid"><generator class="sequence"><param name="sqeuence">SEQ_NUM</param></generator></id><property name="empname" type="string"></property><many-to-one name="dept" column="deptNo" class="Dept"></many-to-one></class></hibernate-mapping>

    @Testpublic void test(){Session session = HibernateUtil.currentSession();Transaction tx = session.beginTransaction();//开始一个事务Dept dept=new Dept();//部门dept.setDeptName("小卖部");session.save(dept);//保存部门对象Emp emp=new Emp();//员工emp.setEmpname("李狗蛋");session.save(emp);tx.commit();//关闭事务
        HibernateUtil.closeSession();}

@Entity
public class HibernateUtil {private static final ThreadLocal<Session> sessionTL=new ThreadLocal<Session>();private static Configuration configuration;private final static SessionFactory sessionFactory;static{try {configuration=new Configuration().configure();sessionFactory=configuration.buildSessionFactory();} catch (Exception e) {e.printStackTrace();throw new ExceptionInInitializerError(e);}}public static Session currentSession(){Session session=sessionTL.get();//如果session为null，则打开一个新的sessionif (session==null) {session=sessionFactory.openSession();sessionTL.set(session);}return session;}public static void closeSession(){Session session=sessionTL.get();sessionTL.set(null);session.close();}
}

private Set<Emp> emps=new HashSet<Emp>();public Set<Emp> getEmps() {return emps;}public void setEmps(Set<Emp> emps) {this.emps = emps;}

 <set name="emps"><key column="DEPTNO"></key><one-to-many class="Emp"></one-to-many></set>

@Testpublic void onetomanyTest(){Session session = HibernateUtil.currentSession();Transaction tx = session.beginTransaction();Dept dept = (Dept)session.load(Dept.class, 1);//建立dept对象和emp对象的一对多双向关联关系Set<Emp> emps = dept.getEmps();for (Emp emp : emps) {System.out.println(emp.getEmpname());}//session.save(dept);//保存dept对象tx.commit();//关闭事务
        HibernateUtil.closeSession();}

@Testpublic void onetomanyTest(){Session session = HibernateUtil.currentSession();Transaction tx = session.beginTransaction();//建立dept对象和emp对象的一对多双向关联关系Dept dept=new Dept();Emp emp=new Emp();dept.setDeptName("中部");emp.setEmpname("张三");emp.setDept(dept);dept.getEmps().add(emp);//session.save(dept);//保存dept对象tx.commit();//关闭事务
        HibernateUtil.closeSession();}