Hibernate表现树状结构

package com.bjsxt.hibernate;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;@Entitypublic class Org {private int id;private String name;private Set<Org> children = new HashSet<Org>();private Org parent;@Id@GeneratedValuepublic 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(cascade=CascadeType.ALL, mappedBy="parent")public Set<Org> getChildren() {return children;}public void setChildren(Set<Org> children) {this.children = children;}@ManyToOne@JoinColumn(name="parent_id")public Org getParent() {return parent;}public void setParent(Org parent) {this.parent = parent;}}

 

junit

package com.bjsxt.hibernate;import java.util.Map;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.cfg.AnnotationConfiguration;import org.hibernate.tool.hbm2ddl.SchemaExport;import org.junit.AfterClass;import org.junit.BeforeClass;import org.junit.Test;public class HibernateTreeTest {private static SessionFactory sessionFactory;@BeforeClasspublic static void beforeClass() {new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();}@AfterClasspublic static void afterClass() {sessionFactory.close();}@Testpublic void testSave() {Org o = new Org();o.setName("总公司");Org o1 = new Org();o1.setName("分公司1");Org o2 = new Org();o2.setName("分公司2");Org o11 = new Org();o11.setName("分公司1下部门1");Org o12 = new Org();o12.setName("分公司1下部门2");o.getChildren().add(o1);o.getChildren().add(o2);o1.getChildren().add(o11);o1.getChildren().add(o12);o11.setParent(o1);o12.setParent(o1);o1.setParent(o);o2.setParent(o);Session session = sessionFactory.openSession();session.beginTransaction();session.save(o);session.getTransaction().commit();session.close();}@Testpublic void testLoad() {testSave();Session session = sessionFactory.openSession();session.beginTransaction();Org o = (Org)session.load(Org.class, 1);print(o, 0);session.getTransaction().commit();session.close();}private void print(Org o, int level) {String preStr = "";for(int i=0; i<level; i++) {preStr += "----";}System.out.println(preStr + o.getName());for(Org child : o.getChildren()) {print(child, level+1);}}@Testpublic void testSchemaExport() {new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);}public static void main(String[] args) {beforeClass();}}