/*
 * $Id$
 *
 * Copyright (C) 2003-2015 JNode.org
 *
 * 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., 
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
package org.jnode.plugin;

/**
 * Descriptor of an "implementation" of an ExtensionPoint.
 *
 * @author Ewout Prangsma (epr@users.sourceforge.net)
 * @see org.jnode.plugin.ExtensionPoint
 */
public interface Extension {

    /**
     * Returns the simple identifier of this extension, or null if this
     * extension does not have an identifier.
     * This identifier is specified in the plug-in manifest (plugin.xml)
     * file as a non-empty string containing no period characters ('.')
     * and must be unique within the defining plug-in.
     *
     * @return The simple identifier
     */
    public abstract String getSimpleIdentifier();

    /**
     * Returns the unique identifier of this extension, or null if this
     * extension does not have an identifier.
     * If available, this identifier is unique within the plug-in registry,
     * and is composed of the identifier of the plug-in that declared this
     * extension and this extension's simple identifier.
     *
     * @return The unique identifier
     */
    public abstract String getUniqueIdentifier();

    /**
     * Gets all child elements
     *
     * @return List<Element>
     */
    public abstract ConfigurationElement[] getConfigurationElements();

    /**
     * Gets the name of the extension-point this extension connects to.
     *
     * @return The unique id of the extension-point
     */
    public String getExtensionPointUniqueIdentifier();

    /**
     * Gets the descriptor of the plugin in which this element was declared.
     *
     * @return The descriptor
     */
    public PluginDescriptor getDeclaringPluginDescriptor();

    public String getExtensionPointPluginId();

}