test3.java

实现树状数据结构

package com.bjsxt.treenode.mode;

import java.util.Iterator;
import java.util.List;
import java.util.Set;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;

import com.bjsxt.treenode.model.Node;

public class Test3 {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		Configuration cfg = new Configuration().configure();
		SessionFactory factory = cfg.buildSessionFactory();
		Session session = factory.openSession();
		Transaction tx = null;

		try {
			tx = session.beginTransaction();

			List roots = session.createQuery("from Node where nodeId is null order by id").list();
			for (Iterator iter = roots.iterator(); iter.hasNext();) {
				Node root = (Node) iter.next();
				nodeRecursion(root);
			}
			

			tx.commit();
		} catch (Exception e) {
			if (tx != null) {
				tx.rollback();
			}
		} finally {
			if (session.isOpen()) {
				session.close();
			}
		}

	}
	
	private static void nodeRecursion(Node node) {
		for (int i=0; i<node.getLevel(); i++) {
			System.out.print("\t");
		}
		
		System.out.println("|-"+node.getName());
		
		Set children = node.getNodes();
		
		if (children != null && !children.isEmpty()) {
			for (Iterator iter = children.iterator(); iter.hasNext();) {
				Node child = (Node) iter.next();
				nodeRecursion(child);
			}
		}
	}

}