/*******************************************************************************
 * Copyright (c) 2007, 2010 Association for Decentralized Information Management
 * in Industry THTH ry.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
package org.simantics.db.common.request;

import java.util.Map;

import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.common.uri.UnescapedChildMapOfResource;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.request.ReadExt;
import org.simantics.db.request.RequestFlags;

final public class PossibleChild extends BinaryRead<Resource, String, Resource> implements ReadExt {

    public PossibleChild(Resource resource, String name) {
        super(resource, name);
    }

    @Override
    public Resource perform(ReadGraph graph) throws DatabaseException {
    	Map<String, Resource> childMap = graph.syncRequest(new UnescapedChildMapOfResource(parameter));
    	return childMap.get(parameter2);
    }
    
    @Override
    public String toString() {
    	return "PossibleChild " + parameter + " " + parameter2;
    }

	@Override
	public boolean isImmutable(ReadGraph graph) throws DatabaseException {
		return graph.isImmutable(parameter);
	}

	@Override
	public int getType() {
		return RequestFlags.IMMEDIATE_UPDATE;
	}

}