/*
 * @(#)$Id: MatcherBundle.java,v 1.2 2001/08/08 00:01:20 Bear Exp $
 *
 * Copyright 2001 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * This software is the proprietary information of Sun Microsystems, Inc.  
 * Use is subject to license terms.
 * 
 */
package com.sun.msv.verifier.identity;

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.relaxng.datatype.Datatype;

/**
 * Base implementation of Matcher coordinator.
 * 
 * This class behaves as a parent of several other matchers, or as a composite
 * XPath matcher.
 * Those child matchers are not directly registered to IDConstraintChecker.
 * Instead, they receive notifications through this object.
 * 
 * @author <a href="mailto:kohsuke.kawaguchi@eng.sun.com">Kohsuke KAWAGUCHI</a>
 */
class MatcherBundle extends Matcher {
	
	/** child matchers. */
	protected Matcher[] children;
	/** depth. */
	private int depth = 0;
	protected final int getDepth() { return depth; }
	
	/**
	 * the derived class must initialize the children field appropriately.
	 */
	protected MatcherBundle( IDConstraintChecker owner ) {
		super(owner);
	}
	
	protected void startElement( String namespaceURI, String localName ) throws SAXException {
		
		depth++;
		for( int i=0; i<children.length; i++ )
			children[i].startElement(namespaceURI,localName);
	}
	
	protected void onAttribute( String namespaceURI, String localName, String value, Datatype type ) throws SAXException {
		for( int i=0; i<children.length; i++ )
			children[i].onAttribute(namespaceURI,localName,value,type);
	}
	
	protected void endElement( Datatype type ) throws SAXException {
		for( int i=0; i<children.length; i++ )
			children[i].endElement(type);
		if( depth-- == 0 ) {
			// traversal complete.
			owner.remove(this);
			onRemoved();
		}
	}

	protected void characters( char[] buf, int start, int len ) throws SAXException {
		for( int i=0; i<children.length; i++ )
			children[i].characters(buf,start,len);
	}
	
	/**
	 * called when this bundle is deactivated.
	 * This method is called by the endElement method when this bundle is
	 * removed. A derived class can override this method to do whatever
	 * necessary.
	 */
	protected void onRemoved() throws SAXException {
	}
}