ItemsetTreeNode.java

package ca.pfv.spmf.algorithms.frequentpatterns.itemsettree;

import java.io.Serializable;
import java.util.Collection;
import java.util.HashSet;
/**
 * This class represents an itemset-tree node.
 * 
 * Copyright (c) 2008-2012 Philippe Fournier-Viger
 * 
 * This file is part of the SPMF DATA MINING SOFTWARE
 * (http://www.philippe-fournier-viger.com/spmf).
 *
 * SPMF is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * SPMF is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with SPMF.  If not, see <http://www.gnu.org/licenses/>.
 */
public class ItemsetTreeNode implements Serializable{
	
	// the itemset
	int[] itemset;
	// the support
	int support;
	// the list of childs
	Collection<ItemsetTreeNode> childs = new HashSet<ItemsetTreeNode>();
	
	/**
	 * The constructor
	 * @param itemset the itemset to be stored in this node.
	 * @param support the support associated to this node.
	 */
	public ItemsetTreeNode(int[] itemset, int support){
		this.itemset = itemset;
		this.support = support;
	}

	/**
	 * Return a string representation of this node
	 * @param buffer a strinbuffer for appending a string representation
	 * @param space the indentation that should be used on each line
	 * @return the updated buffer as a string.
	 */
	public String toString(StringBuilder buffer, String space){
		buffer.append(space);
		if(itemset == null){
			buffer.append("{}");
		}else{
			buffer.append("[");
			for(Integer item : itemset){
				buffer.append(item);
				buffer.append(" ");
			}
			buffer.append("]");
		}
		buffer.append("   sup=");
		buffer.append(support);
		buffer.append("\n");
		
		for(ItemsetTreeNode node : childs){
			node.toString(buffer, space + "  ");
		}
		return buffer.toString();
	}
	
	public String toString(){
		return toString(new StringBuilder(), "  ");
	}
	
}