Hibernate映射树形结构

Orgnization.java

package com.test.hiberenate.model;

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

import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;

@Entity
public class Orgnization {
	private int id;
	private String name;
	private Set<Orgnization> children = new HashSet<Orgnization>();
	private Orgnization parent;

	@Id
	@GeneratedValue
	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;
	}

	@OneToMany(mappedBy = "parent", cascade = CascadeType.ALL, fetch = FetchType.EAGER)
	public Set<Orgnization> getChildren() {
		return children;
	}

	public void setChildren(Set<Orgnization> children) {
		this.children = children;
	}

	@ManyToOne
	@JoinColumn(name = "parent_id")
	public Orgnization getParent() {
		return parent;
	}

	public void setParent(Orgnization parent) {
		this.parent = parent;
	}

}

 

HibernateTreeTest.java

package com.test.hibernate.model;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;

import com.test.hiberenate.model.Orgnization;

public class HibernateTreeTest {
	private static SessionFactory sf = null;

	@BeforeClass
	public static void beforeClass() {
		new SchemaExport(new Configuration().configure()).create(false, true);
		try {
			if (sf == null) {
				sf = new Configuration().configure().buildSessionFactory();
			}
		} catch (HibernateException e) {
			e.printStackTrace();
		}
	}

	@AfterClass
	public static void afterClass() {
		sf.close();
	}

	@Test
	public void testSave() {
		Orgnization o = new Orgnization();
		o.setName("总公司");
		Orgnization o1 = new Orgnization();
		o1.setName("分公司1");
		Orgnization o2 = new Orgnization();
		o2.setName("分公司2");
		Orgnization o21 = new Orgnization();
		o21.setName("分公司2下部门1");
		Orgnization o22 = new Orgnization();
		o22.setName("分公司2下部门2");
		o.getChildren().add(o1);
		o.getChildren().add(o2);
		o2.getChildren().add(o21);
		o2.getChildren().add(o22);
		o1.setParent(o);
		o2.setParent(o);
		o21.setParent(o2);
		o22.setParent(o2);

		Session session = sf.openSession();
		session.beginTransaction();
		session.save(o);
		session.getTransaction().commit();
		session.close();
	}

	@Test
	public void testLoad() {
		testSave();
		Session session = sf.openSession();
		session.beginTransaction();
		Orgnization o = (Orgnization) session.load(Orgnization.class, 1);
		this.printChildren(o, 0);
		session.getTransaction().commit();
		session.close();
	}

	private void printChildren(Orgnization o, int level) {
		String str = "";
		for (int i = 0; i < level; i++) {
			str += "---";
		}
		System.out.println(str + o.getName());
		for (Orgnization children : o.getChildren()) {
			this.printChildren(children, level + 1);
		}
	}

	public static void main(String[] args) {
		beforeClass();
	}

}