/*
 This file is part of the software framework JStatCom, 
 a library for building applications for data based analysis.

 Copyright (C) 2000-2005  Markus Kraetzig

 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 com.jstatcom.engine.ox;

import java.util.Map;

import com.jstatcom.engine.ConfigHolder;
import com.jstatcom.engine.ConfigKeys;
import com.jstatcom.engine.Engine;
import com.jstatcom.engine.EngineTypes;

/**
 * Holds information about the OxEngine and binds different
 * classes together as a Mediator. It is a Singleton.
 * 
 * @author Markus Kraetzig 
 */
public final class OxEngineType extends EngineTypes {

    /**
     * Singleton instance of this class.
     */
    public static final OxEngineType INSTANCE = new OxEngineType("Ox");

    private OxEngine oxEngine = null;

    /**
     * Create a OxEngineType.
     * 
     * @param name
     *            the name of the type
     */
    private OxEngineType(String name) {
        super(name);
    }

    /*
     * @see com.jstatcom.engine.EngineTypes#checkSettings(com.jstatcom.engine.ConfigHolder)
     */
    public String checkSettings(ConfigHolder configHolder) {
        // nothing to do, because settings are independent
        return null;
    }

    /*
     * @see com.jstatcom.engine.EngineTypes#getConfigKeys()
     */
    public Map getConfigKeys() {
        return ConfigKeys.getAllKeys(OxConfigKeys.class);

    }

    /*
     * @see com.jstatcom.engine.EngineTypes#getEngine()
     */
    public Engine getEngine() {
        if (oxEngine == null) {
            try {
                oxEngine = OxEngine.getInstance();
            } catch (Throwable ex) {
                throw new RuntimeException(
                        "The Ox engine could not be initialized\ndue to the following error:\n\n"
                                + ex.getMessage() + "\n");
            }
        }
        addLoadedEngine(oxEngine);
        return oxEngine;
    }
}