Token.java

/*
 * Copyright 2006 - 2013
 *     Stefan Balev     <stefan.balev@graphstream-project.org>
 *     Julien Baudry    <julien.baudry@graphstream-project.org>
 *     Antoine Dutot    <antoine.dutot@graphstream-project.org>
 *     Yoann Pign��      <yoann.pigne@graphstream-project.org>
 *     Guilhelm Savin   <guilhelm.savin@graphstream-project.org>
 * 
 * This file is part of GraphStream <http://graphstream-project.org>.
 * 
 * GraphStream is a library whose purpose is to handle static or dynamic
 * graph, create them from scratch, file or any source and display them.
 * 
 * This program is free software distributed under the terms of two licenses, the
 * CeCILL-C license that fits European law, and the GNU Lesser General Public
 * License. You can  use, modify and/ or redistribute the software under the terms
 * of the CeCILL-C license as circulated by CEA, CNRS and INRIA at the following
 * URL <http://www.cecill.info> or under the terms of the GNU LGPL as published by
 * the Free Software Foundation, either version 3 of the License, or (at your
 * option) any later version.
 * 
 * This program 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, see <http://www.gnu.org/licenses/>.
 * 
 * The fact that you are presently reading this means that you have had
 * knowledge of the CeCILL-C and LGPL licenses and that you accept their terms.
 */
package org.graphstream.util.parser;

/**
 * Describes the input token stream.
 */

public class Token implements java.io.Serializable {

	/**
	 * The version identifier for this Serializable class. Increment only if the
	 * <i>serialized</i> form of the class changes.
	 */
	private static final long serialVersionUID = 1L;

	/**
	 * An integer that describes the kind of this token. This numbering system
	 * is determined by JavaCCParser, and a table of these numbers is stored in
	 * the file ...Constants.java.
	 */
	public int kind;

	/** The line number of the first character of this Token. */
	public int beginLine;
	/** The column number of the first character of this Token. */
	public int beginColumn;
	/** The line number of the last character of this Token. */
	public int endLine;
	/** The column number of the last character of this Token. */
	public int endColumn;

	/**
	 * The string image of the token.
	 */
	public String image;

	/**
	 * A reference to the next regular (non-special) token from the input
	 * stream. If this is the last token from the input stream, or if the token
	 * manager has not read tokens beyond this one, this field is set to null.
	 * This is true only if this token is also a regular token. Otherwise, see
	 * below for a description of the contents of this field.
	 */
	public Token next;

	/**
	 * This field is used to access special tokens that occur prior to this
	 * token, but after the immediately preceding regular (non-special) token.
	 * If there are no such special tokens, this field is set to null. When
	 * there are more than one such special token, this field refers to the last
	 * of these special tokens, which in turn refers to the next previous
	 * special token through its specialToken field, and so on until the first
	 * special token (whose specialToken field is null). The next fields of
	 * special tokens refer to other special tokens that immediately follow it
	 * (without an intervening regular token). If there is no such token, this
	 * field is null.
	 */
	public Token specialToken;

	/**
	 * An optional attribute value of the Token. Tokens which are not used as
	 * syntactic sugar will often contain meaningful values that will be used
	 * later on by the compiler or interpreter. This attribute value is often
	 * different from the image. Any subclass of Token that actually wants to
	 * return a non-null value can override this method as appropriate.
	 */
	public Object getValue() {
		return null;
	}

	/**
	 * No-argument constructor
	 */
	public Token() {
	}

	/**
	 * Constructs a new token for the specified Image.
	 */
	public Token(int kind) {
		this(kind, null);
	}

	/**
	 * Constructs a new token for the specified Image and Kind.
	 */
	public Token(int kind, String image) {
		this.kind = kind;
		this.image = image;
	}

	/**
	 * Returns the image.
	 */
	public String toString() {
		return image;
	}

	/**
	 * Returns a new Token object, by default. However, if you want, you can
	 * create and return subclass objects based on the value of ofKind. Simply
	 * add the cases to the switch for all those special cases. For example, if
	 * you have a subclass of Token called IDToken that you want to create if
	 * ofKind is ID, simply add something like :
	 * 
	 * case MyParserConstants.ID : return new IDToken(ofKind, image);
	 * 
	 * to the following switch statement. Then you can cast matchedToken
	 * variable to the appropriate type and use sit in your lexical actions.
	 */
	public static Token newToken(int ofKind, String image) {
		switch (ofKind) {
		default:
			return new Token(ofKind, image);
		}
	}

	public static Token newToken(int ofKind) {
		return newToken(ofKind, null);
	}

}
/*
 * JavaCC - OriginalChecksum=0c00a7ff8fbeeb2312a89d5c1c4252da (do not edit this
 * line)
 */