1. 程式人生 > >Hibernate關聯關係對映-----基於連線表的單向一對多對映

Hibernate關聯關係對映-----基於連線表的單向一對多對映

實體:

package uni.many2one.jointable;

public class Parent {
	private int id;
	private String name;
	private Child child;

	public Parent() {
	}

	public Parent(int id, String name, Child child) {
		super();
		this.id = id;
		this.name = name;
		this.child = child;
	}

	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 Child getChild() {
		return child;
	}

	public void setChild(Child child) {
		this.child = child;
	}

}

package uni.many2one.jointable;

public class Child {
	private int id;
	private String name;

	public Child(int id, String name) {
		super();
		this.id = id;
		this.name = name;
	}

	public Child() {
	}

	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;
	}
}

hm配置檔案:
<hibernate-mapping>
	<!-- <class name="org.hibernate.wk.Student" dynamic-insert="true" dynamic-update="true"> -->
	<class name="uni.many2one.jointable.Parent">
		<id name="id" column="did">
			<generator class="native" />
		</id>
		<property name="name" type="string" column="name"></property>
		
		<join table="parentchild">
			<key column="did"></key>
			<many-to-one name="child" column="cid" not-null="true"></many-to-one>
		</join>
	</class>

</hibernate-mapping>
<hibernate-mapping>
	<class name="uni.many2one.jointable.Child">
		<id name="id" column="id">
			<generator class="native" />
		</id>
		<property name="name" type="string" column="name"></property>
	</class>

</hibernate-mapping>

測試檔案:
public class Test {
	
	@org.junit.Test
	public void testAdd() {
		SessionFactory sf = HibernateUtil.getSessionFactory();
		Session session = sf.getCurrentSession();
		session.beginTransaction();
		Child c1 = new Child();
		c1.setName("child1");

		Parent mother = new Parent();
		mother.setName("Mother");
		mother.setChild(c1);
		
		Parent father = new Parent();
		father.setName("Daddy");
		father.setChild(c1);
		
		session.save(c1);
		session.save(mother);
		session.save(father);
		session.beginTransaction().commit();
		
	}
	
}

測測試結果:
Hibernate: insert into Child (name) values (?)
Hibernate: insert into Parent (name) values (?)
Hibernate: insert into parentchild (cid, did) values (?, ?)
Hibernate: insert into Parent (name) values (?)
Hibernate: insert into parentchild (cid, did) values (?, ?)