/*
 *
 *
 * Copyright  1990-2007 Sun Microsystems, Inc. All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 only, as published by the Free Software Foundation.
 * 
 * This program 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
 * General Public License version 2 for more details (a copy is
 * included at /legal/license.txt).
 * 
 * You should have received a copy of the GNU General Public License
 * version 2 along with this work; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 * 
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
 * Clara, CA 95054 or visit www.sun.com if you need additional
 * information or have any questions.
 */

package com.sun.midp.services;

import com.sun.midp.main.MIDletSuiteUtils;
import com.sun.midp.security.SecurityToken;
import com.sun.midp.security.Permissions;

/**
 * Keeps track of available services.
 */
public abstract class SystemServiceManager {
    private static SystemServiceManager instance = null;


    /**
     * Gets class instance.
     *
     * @return SystemServiceManage class instance
     */
    synchronized public static SystemServiceManager getInstance(
            SecurityToken token) {

        token.checkIfPermissionAllowed(Permissions.MIDP);

        if (instance == null) {
            if (MIDletSuiteUtils.isAmsIsolate()) {
                instance = new SystemServiceManagerImpl();
            }
        }

        return instance;
    }

    /**
     * Registers service.
     *
     * @param service service to register
     */
    abstract public void registerService(SystemService service);


    /**
     * Gets registered service.
     *
     * @param serviceID unique service ID
     * @return service corresponding to specified ID
     */
    abstract public SystemService getService(String serviceID);

    /**
     * Shutdowns service manager
     */
    abstract public void shutdown();
}