/*
 * FindBugs - Find Bugs in Java programs
 * Copyright (C) 2006, University of Maryland
 * 
 * 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 library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package edu.umd.cs.findbugs.filter;

import java.util.HashSet;
import java.util.Set;
import java.util.StringTokenizer;

/**
 * Matches a string against a set of predefined values.
 * 
 * Value set is defined using a String containing a comma separated value list.
 * Heading an trailing whitespace on the values is ignored in matching.
 * 
 * @author rak
 */
public class StringSetMatch {
	private Set<String> strings = new HashSet<String>();

	@Override
    public int hashCode() {
		return strings.hashCode();
	}
	@Override
    public boolean equals(Object o) {
		if (!(o instanceof StringSetMatch)) return false;
		return strings.equals(((StringSetMatch)o).strings);
	}
	/**
	 * Constructor.
	 * 
	 * @param strings comma-separated list of Strings
	 */
	public StringSetMatch(String strings) {
		if (strings != null) {
			StringTokenizer tok = new StringTokenizer(strings, ",");
			while (tok.hasMoreTokens()) {
				this.strings.add(tok.nextToken().trim());
			}
		}
	}

	public boolean isEmpty() {
		return strings.isEmpty();
	}
	/**
	 * Returns true if the given string is contained in the value set.
	 * 
	 * @param string
	 * @return true if the given string is contained in the value set
	 */
	public boolean match(String string) {
		return strings.contains(string.trim());
	}
	
	@Override
	public String toString() {
		if (strings.isEmpty()) return "";
		StringBuilder result = new StringBuilder();
		for(String s : strings)
			result.append(s).append(",");
		return result.substring(0, result.length()-1);
	}
}
