AbstractToken.java

/**
 *  Copyright (C) 2010 dennis zhuang (killme2008@gmail.com)
 *
 *  This library is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published
 *  by the Free Software Foundation; either version 2.1 of the License, or
 *  (at your option) any later version.
 *
 *  This library 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 Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 **/
package com.googlecode.aviator.lexer.token;

/**
 * Base token class
 * 
 * @author dennis
 * 
 * @param <T>
 */
public abstract class AbstractToken<T> implements Token<T> {

    private final int startIndex;

    protected final String lexeme;


    public AbstractToken(int startIndex, String lexeme) {
        super();
        this.startIndex = startIndex;
        this.lexeme = lexeme;
    }


    public String getLexeme() {
        return this.lexeme;
    }


    public int getStartIndex() {
        return this.startIndex;
    }


    @Override
    public String toString() {
        return "[" + getType().name() + " " + getLexeme() + ",index=" + startIndex + "]";
    }


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


    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        AbstractToken<?> other = (AbstractToken<?>) obj;
        if (lexeme == null) {
            if (other.lexeme != null) {
                return false;
            }
        }
        else if (!lexeme.equals(other.lexeme)) {
            return false;
        }
        if (startIndex != other.startIndex) {
            return false;
        }
        return true;
    }

}