/*
 * FindBugs - Find bugs in Java programs
 * Copyright (C) 2003-2005, 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.io.IOException;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedHashSet;

import edu.umd.cs.findbugs.xml.XMLOutput;

public abstract class CompoundMatcher implements Matcher {
    protected LinkedHashSet<Matcher> children = new LinkedHashSet<Matcher>();

    @Override
    public int hashCode() {
        int result = this.getClass().hashCode();
        for (Matcher m : children) {
            result += m.hashCode();
        }
        return result;
    }

    @Override
    public boolean equals(Object o) {
        if (o == null) {
            return false;
        }
        if (o.getClass() != this.getClass()) {
            return false;
        }
        CompoundMatcher m = (CompoundMatcher) o;
        return children.equals(m.children);
    }

    protected int numberChildren() {
        return children.size();
    }

    public void addChild(Matcher child) {
        children.add(child);
    }

    protected void removeChild(Matcher child) {
        children.remove(child);
    }

    protected void clear() {
        children.clear();
    }

    public Collection<Matcher> getChildren() {
        return Collections.unmodifiableCollection(children);
    }

    public Iterator<Matcher> childIterator() {
        return children.iterator();
    }

    public void writeChildrenXML(XMLOutput xmlOutput) throws IOException {
        for (Matcher m : children) {
            m.writeXML(xmlOutput, false);
        }
    }

    @Override
    public String toString() {
        if (children.isEmpty()) {
            return "";
        }
        StringBuilder buf = new StringBuilder();
        for (Matcher m : children) {
            buf.append(m).append(" ");
        }
        buf.setLength(buf.length() - 1);
        return buf.toString();
    }

    public int maxChildren() {
        return Integer.MAX_VALUE;
    }
}

