GenericParseAttribute.java

/*
 * 
 * Copyright 2012 lexergen.
 * This file is part of lexergen.
 * 
 * lexergen 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.
 * 
 * lexergen 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 lexergen.  If not, see <http://www.gnu.org/licenses/>.
 *  
 * lexergen:
 * A tool to chunk source code into tokens for further processing in a compiler chain.
 * 
 * Projectgroup: bi, bii
 * 
 * Authors: Johannes Dahlke
 * 
 * Module:  Softwareprojekt Übersetzerbau 2012 
 * 
 * Created: Apr. 2012 
 * Version: 1.0
 *
 */

package de.fuberlin.bii.tokenmatcher.attributes;

import de.fuberlin.bii.utils.Test;

/**
 * Generische Basisklasse für Attribute, deren Wert 
 * nicht in Tokendefinitionsdatei angeben ist, 
 * sondern aus dem geparsten Lexem hervorgeht.
 * 
 * @author Johannes Dahlke
 *
 * @param <T>
 */
public abstract class GenericParseAttribute<T> implements Attribute {

	/**
	 * 
	 */
	private static final long serialVersionUID = 4152632396959708006L;
	private String lexem;
	private final Class<T> valueType;
	
	public GenericParseAttribute( Class<T> valueType) {
	  super();
	  this.valueType = valueType;
	}
	
	public Object lexemToValue( String lexem) {
		this.lexem = lexem;
	  return parseLexem( lexem);	
	}
	
	protected abstract Object parseLexem( String lexem);

	public Class<Integer> getValueType() {
		return Integer.class;
	}

	@Override
	public String toString() {
		return lexem;
	}
	
	@Override
	public boolean equals( Object obj) {
		if ( Test.isUnassigned( obj))
			return false;
		
		if ( !( obj instanceof GenericParseAttribute))
			return false;
		
		@SuppressWarnings("unchecked")
		final GenericParseAttribute<T> theOtherGenericParseAttribute = (GenericParseAttribute<T>) obj;
		
		boolean isEqual = theOtherGenericParseAttribute.valueType.equals( this.valueType) 
				&& theOtherGenericParseAttribute.lexem.equals( this.lexem);
		
		return isEqual;
	}
	
	@Override
	public int hashCode() {
		int hashCode = 5;
		hashCode = 31 * hashCode + this.valueType.hashCode();
		hashCode = 31 * hashCode + (Test.isAssigned( this.lexem) ? this.lexem.hashCode() : 0);
		
		return hashCode;
	}
	
}