/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you under the Apache
 *   License, Version 2.0 (the "License"); you may not use this file
 *   except in compliance with the License. You may obtain a copy of
 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
 */

package com.sun.star.comp.connections;

import com.sun.star.bridge.XInstanceProvider;

import com.sun.star.lang.XMultiServiceFactory;
import com.sun.star.lang.XSingleServiceFactory;

import com.sun.star.registry.XRegistryKey;

import com.sun.star.comp.loader.FactoryHelper;


/**
 * The <code>ConstantInstanceProvider</code> is a component
 * that implements the <code>XInstanceProvider</code> Interface.
 *
 * @see         com.sun.star.bridge.XBridge
 * @see         com.sun.star.bridge.XBridgeFactory
 * @see         com.sun.star.bridge.XInstanceProvider
 * @see         com.sun.star.comp.loader.JavaLoader
 * @since       UDK1.0
 */
public class ConstantInstanceProvider implements XInstanceProvider {
    /**
     * When set to true, enables various debugging output.
     */
    static public final boolean DEBUG = false;

    /**
     * The name of the service, the <code>JavaLoader</code> acceses this through
     * reflection.
     */
    static private final String __serviceName = "com.sun.star.comp.connection.InstanceProvider";

    /**
     * Gives a factory for creating the service.
     * <p>This method is called by the <code>JavaLoader</code>.</p>
     *
     * @param   implName     the name of the implementation for which a service is desired.
     * @param   multiFactory the service manager to be uses if needed.
     * @param   regKey       the registryKey.
     * @return  returns a <code>XSingleServiceFactory</code> for creating the component.
     *
     * @see                  com.sun.star.comp.loader.JavaLoader
     */
    public static XSingleServiceFactory __getServiceFactory(String implName,
                                                            XMultiServiceFactory multiFactory,
                                                            XRegistryKey regKey)
    {
        XSingleServiceFactory xSingleServiceFactory = null;

        if (implName.equals(ConstantInstanceProvider.class.getName()) )
            xSingleServiceFactory = FactoryHelper.getServiceFactory(ConstantInstanceProvider.class,
                                                                    __serviceName,
                                                                    multiFactory,
                                                                    regKey);

        return xSingleServiceFactory;
    }

    protected XMultiServiceFactory _serviceManager;
    protected String _serviceName;
    protected Object _instance;


    public void setInstance(String serviceName) throws com.sun.star.uno.Exception {
        _instance = _serviceManager.createInstance(serviceName);
        _serviceName = serviceName;
    }

    /**
     * Constructs a new <code>ConstantInstanceProvider</code>.
     * <p>Uses the provided ServiceManager as the provided instance.</p>
     *
     * @param    serviceManager   the provided service manager
     */
    public ConstantInstanceProvider(XMultiServiceFactory serviceManager) {
        _serviceManager = serviceManager;

        _serviceName = "SERVICEMANAGER";
        _instance    = serviceManager;
    }

    /**
     * Gives an object for the passed instance name.
     *
     * @return  the desired instance
     * @param   sInstanceName   the name of the desired instance
     */
    public Object getInstance(String sInstanceName) throws com.sun.star.container.NoSuchElementException, com.sun.star.uno.RuntimeException {
        Object result = sInstanceName.equals(_serviceName) ? _instance : null;

        if(DEBUG) System.err.println("##### " + getClass().getName() + ".getInstance(" + sInstanceName + "):" + result);

        return result;
    }
}

