/*
 * @(#)$Id: ImportState.java,v 1.7 2002/03/04 02:12:05 kk122374 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.reader.xmlschema;

import com.sun.msv.reader.AbortException;
import com.sun.msv.reader.ChildlessState;

/**
 * used to parse <import> element.
 * 
 * @author <a href="mailto:kohsuke.kawaguchi@eng.sun.com">Kohsuke KAWAGUCHI</a>
 */
public class ImportState extends ChildlessState {
	
	protected void startSelf() {
		super.startSelf();
		final XMLSchemaReader reader = (XMLSchemaReader)this.reader;
		
		// TODO: @schemaLocation is optional.
		String namespace = startTag.getAttribute("namespace");
		if( namespace==null )   namespace="";
		
		if( namespace.equals(reader.currentSchema.targetNamespace) ) {
			reader.reportError( reader.ERR_IMPORTING_SAME_NAMESPACE );
			return;
		}
		
		if( reader.isSchemaDefined( reader.getOrCreateSchema(namespace) ) )
			// this grammar is already defined.
			// so ignore it.
			return;
				
        try {
    		reader.switchSource( this,
	    		new RootIncludedSchemaState(reader.sfactory.schemaHead(namespace)) );
        } catch( AbortException e ) {
            // recover by ignoring the error
        }
	}
}