IdRefTokenizer.java

/**********************************************
 * Copyright (C) 2010 Lukas Laag
 * This file is part of svgreal.
 * 
 * svgreal 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.
 * 
 * svgreal 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 svgreal.  If not, see http://www.gnu.org/licenses/
 **********************************************/
package org.vectomatic.svg.edit.client.engine;

/**
 * Class to split SVG attribute values into a stream of
 * tokens. Each token is either a piece of text to be
 * quoted verbatim by the SVG id normalizer, or an idref
 * to be replaced by a normalized id ref.
 * @author laaglu
 */
public class IdRefTokenizer {
	protected static final String START = "url(#";
	protected static final String END = ")";
	static class IdRefToken {
		public static final int IDREF = 1;
		public static final int DATA = 2;
		int kind;
		String value;
		public int getKind() {
			return kind;
		}
		public String getValue() {
			return value;
		}
	}
	protected IdRefToken token = new IdRefToken();
	protected String str;
	protected int index1;
	protected int index2;

	public void tokenize(String str) {
		this.str = str;
		index1 = 0;
		index2 = 0;
		token.kind = IdRefToken.IDREF;
		token.value = null;
	}
	public IdRefToken nextToken() {
		if (index1 != str.length()) {
			if (token.kind == IdRefToken.IDREF) {
				token.kind = IdRefToken.DATA;
				index2 = str.indexOf(START, index1);
				if (index2 != -1) {
					token.value = str.substring(index1, index2 + START.length());
					index1 = index2 + START.length();
				} else {
					token.value = str.substring(index1);
					index1 = str.length();
				}
			} else {
				index2 = str.indexOf(END, index1);
				if (index2 != -1) {
					token.value = str.substring(index1, index2);
					index1 = index2;
					token.kind = IdRefToken.IDREF;
				} else {
					token.value = str.substring(index1);
					index1 = str.length();
				}
			}
			return token;
		}
		return null;
	}
}