org.eclipse.viatra2.gtasm.patternmatcher.incremental/src/org/eclipse/viatra2/gtasm/patternmatcher/incremental/simple/legacy/PatternNodeBase.java

/*******************************************************************************
 * Copyright (c) 2004-2010 Gabor Bergmann and Daniel Varro
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Gabor Bergmann - initial API and implementation
 *******************************************************************************/

package org.eclipse.viatra2.gtasm.patternmatcher.incremental.simple.legacy;

import java.util.HashSet;
import java.util.LinkedList;

/**
 * @author Bergmann Gábor
 *
 */
public class PatternNodeBase {

	/**
	 * The name of the pattern variable. This is the unique key of the pattern node.
	 */
	public String name;
	/**
	 * if a node is not a symbolic parameter nor is it touched (quantified) by any
	 * nonnegative constraints, it should be inversely quantified
	 */
	public boolean isTouched;
	/**
	 * virtual pNodes are nodes that do not correspond to actual pattern
	 * variables; they represent constants or Term substitutes
	 */
	public boolean isVirtual;
	/**
	 * true if node is explicitly made exempt from injectivity
	 */
	public boolean isExemptFromInjectivity = false;
	/**
	 * Counts the number of hitherto unmatched constraints that can restrict the type of the node
	 */
	public int lingeringTypeInfoCounter;
	/**
	 * types explicitly asserted of this node
	 */
	public LinkedList<Object> assertedTypes;
	/**
	 * types automatically implied by other constraints
	 */
	public HashSet<Object> impliedTypes;


	/**
	 * @param name
	 * @param isTouched
	 * @param isVirtual
	 */
	public PatternNodeBase(String name, boolean isTouched, boolean isVirtual) {
		super();
		this.name = name;
		this.isTouched = isTouched;
		this.isVirtual = isVirtual;
		
		this.assertedTypes = new LinkedList<Object>();
		this.impliedTypes = new HashSet<Object>();
		this.lingeringTypeInfoCounter = 0;
		
	}

	public PatternNodeBase(String name) {
		this(name, false, false);
	}
	

	public boolean isVirtual() {
		return isVirtual;
	}

	public boolean isExemptFromInjectivity() {
		return isVirtual || isExemptFromInjectivity;
	}

	public void makeExemptFromInjectivity() {
		isExemptFromInjectivity = true;
	}

	@Override
	public int hashCode() {
		final int PRIME = 31;
		int result = 1;
		result = PRIME * result + ((name == null) ? 0 : name.hashCode());
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		final PatternNode other = (PatternNode) obj;
		if (name == null) {
			if (other.name != null)
				return false;
		} else if (!name.equals(other.name))
			return false;
		return true;
	}

	public int compareTo(PatternNode arg0) {
		return name.compareTo(arg0.name);
	}

	@Override
	public String toString() {
		return name;// + ":PatternNode";
	}

}