迷失北京

package bi.one2many.jointable;

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

public class Emperor {
	private int id;
	private String name;
	private Set<Minister> ministers = new HashSet<Minister>();

	public Emperor() {

	}

	public Emperor(int id, String name, Set<Minister> ministers) {
		super();
		this.id = id;
		this.name = name;
		this.ministers = ministers;
	}

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public Set<Minister> getMinisters() {
		return ministers;
	}

	public void setMinisters(Set<Minister> ministers) {
		this.ministers = ministers;
	}

}

package bi.one2many.jointable;

public class Minister {
	private int id;
	private String name;
	private Emperor emperor;

	public Minister() {

	}

	public Minister(int id, String name, Emperor emperor) {
		super();
		this.id = id;
		this.name = name;
		this.emperor = emperor;
	}

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public Emperor getEmperor() {
		return emperor;
	}

	public void setEmperor(Emperor emperor) {
		this.emperor = emperor;
	}

}

<hibernate-mapping>
	<class name="bi.one2many.jointable.Emperor">
		<id name="id" column="eid">
			<generator class="native" />
		</id>
		<property name="name" type="string" column="name"></property>
		
		<!-- confirure the uniredirection association -->
		<set name="ministers" table="emperorminister" inverse="true" >
			<key column="eid" not-null="true"></key>
			<many-to-many column="mid" unique="true" class="bi.one2many.jointable.Minister"/>
		</set>
	</class>

</hibernate-mapping>
<hibernate-mapping>
	<class name="bi.one2many.jointable.Minister">
		<id name="id" column="mid">
			<generator class="native" />
		</id>
		<property name="name" type="string" column="name"></property>
	
		<join table="emperorminister" optional="true"  >
			<key column="mid"></key>
			<many-to-one name="emperor" column="eid" not-null="true"></many-to-one>
		</join>
	</class>

</hibernate-mapping>

public class Test {
	
	@org.junit.Test
	public void testAdd() {
		SessionFactory sf = HibernateUtil.getSessionFactory();
		Session session = sf.getCurrentSession();
		session.beginTransaction();
		
		Minister m1 = new Minister();
		m1.setName("廉頗");
		
		Minister m2 = new Minister();
		m2.setName("藺相如");
		
		Emperor emperor = new Emperor();
		emperor.setName("齊威王");
		//emperor.getMinisters().add(m1);
		//emperor.getMinisters().add(m2);
		
		m1.setEmperor(emperor);
		m2.setEmperor(emperor);
		
		session.save(emperor);
		session.save(m1);
		session.save(m2);
		session.beginTransaction().commit();
	}
}

Hibernate: insert into Emperor (name) values (?)
Hibernate: insert into Minister (name) values (?)
Hibernate: insert into emperorminister (eid, mid) values (?, ?)
Hibernate: insert into Minister (name) values (?)
Hibernate: insert into emperorminister (eid, mid) values (?, ?)