/*
 * Copyright (c) OSGi Alliance (2009, 2010). All Rights Reserved.
 * 
 * Licensed 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
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.osgi.jmx.framework;

import java.io.IOException;

import javax.management.openmbean.CompositeType;
import javax.management.openmbean.SimpleType;
import javax.management.openmbean.TabularData;
import javax.management.openmbean.TabularType;

import org.osgi.jmx.Item;
import org.osgi.jmx.JmxConstants;

/**
 * This MBean represents the Service state of the framework. This MBean also
 * emits events that clients can use to get notified of the changes in the
 * service state of the framework.
 * 
 * @version $Id: 52e2ca739e54283040bde80cbd2e0e8bad3022d4 $
 * @ThreadSafe
 */
public interface ServiceStateMBean {
	/**
	 * The fully qualified object name of this mbean.
	 */
	String OBJECTNAME = JmxConstants.OSGI_CORE
			+ ":type=serviceState,version=1.5";
	/**
	 * The key BUNDLE_IDENTIFIER, used in {@link #BUNDLE_IDENTIFIER_ITEM}.
	 */
	String BUNDLE_IDENTIFIER = "BundleIdentifier";
	/**
	 * The item containing the bundle identifier in {@link #SERVICE_TYPE}. The
	 * key is {@link #BUNDLE_IDENTIFIER} and the type is {@link SimpleType#LONG}
	 * .
	 */
	Item BUNDLE_IDENTIFIER_ITEM = new Item(BUNDLE_IDENTIFIER,
			"The identifier of the bundle the service belongs to",
			SimpleType.LONG);

	/**
	 * The key OBJECT_CLASS, used {@link #OBJECT_CLASS_ITEM}.
	 */
	String OBJECT_CLASS = "objectClass";

	/**
	 * The item containing the interfaces of the service in
	 * {@link #SERVICE_TYPE}. The key is {@link #OBJECT_CLASS} and the type is
	 * {@link JmxConstants#STRING_ARRAY_TYPE}.
	 */
	Item OBJECT_CLASS_ITEM = new Item(
			OBJECT_CLASS,
			"An string array containing the interfaces under which the service has been registered",
			JmxConstants.STRING_ARRAY_TYPE);

	/**
	 * The key IDENTIFIER, used {@link #IDENTIFIER_ITEM}.
	 */
	String IDENTIFIER = "Identifier";

	/**
	 * The item containing the service identifier in {@link #SERVICE_TYPE}. The
	 * key is {@link #IDENTIFIER} and the type is {@link SimpleType#LONG}.
	 */
	Item IDENTIFIER_ITEM = new Item(IDENTIFIER,
			"The identifier of the service", SimpleType.LONG);

	/**
	 * The key USING_BUNDLES, used in {@link #USING_BUNDLES_ITEM}.
	 */
	String USING_BUNDLES = "UsingBundles";

	/**
	 * The item containing the bundles using the service in
	 * {@link #SERVICE_TYPE}. The key is {@link #USING_BUNDLES} and the type is
	 * {@link JmxConstants#LONG_ARRAY_TYPE}.
	 */
	Item USING_BUNDLES_ITEM = new Item(USING_BUNDLES,
			"The bundles using the service", JmxConstants.LONG_ARRAY_TYPE);

	/**
	 * The Composite Type for a CompositeData representing a service. This type
	 * consists of:
	 * <ul>
	 * <li>{@link #BUNDLE_IDENTIFIER}</li>
	 * <li>{@link #IDENTIFIER}</li>
	 * <li>{@link #OBJECT_CLASS}</li>
	 * <li>{@link #USING_BUNDLES}</li>
	 * </ul>
	 */
	CompositeType SERVICE_TYPE = Item.compositeType("SERVICE",
			"This type encapsulates an OSGi service", BUNDLE_IDENTIFIER_ITEM,
			IDENTIFIER_ITEM, OBJECT_CLASS_ITEM,
			USING_BUNDLES_ITEM);

	/**
	 * The Tabular Type for a Service table. The rows consists of
	 * {@link #SERVICE_TYPE} Composite Data and the index is {@link #IDENTIFIER}
	 * .
	 */
	TabularType SERVICES_TYPE = Item.tabularType("SERVICES",
			"The table of all services", SERVICE_TYPE, IDENTIFIER);

	/**
	 * The key BUNDLE_LOCATION, used in {@link #SERVICE_EVENT_TYPE}.
	 */
	String BUNDLE_LOCATION = "BundleLocation";
	/**
	 * The item containing the bundle location in {@link #EVENT_ITEM}. The key
	 * is {@link #BUNDLE_LOCATION} and the the type is {@link SimpleType#STRING}
	 * .
	 */
	Item BUNDLE_LOCATION_ITEM = new Item(BUNDLE_LOCATION,
			"The location of the bundle", SimpleType.STRING);
	/**
	 * The key BUNDLE_SYMBOLIC_NAME, used in {@link #SERVICE_EVENT_TYPE}.
	 */
	String BUNDLE_SYMBOLIC_NAME = "BundleSymbolicName";

	/**
	 * The item containing the symbolic name in {@link #EVENT}. The key is
	 * {@link #BUNDLE_SYMBOLIC_NAME} and the the type is
	 * {@link SimpleType#STRING}.
	 */
	Item BUNDLE_SYMBOLIC_NAME_ITEM = new Item(BUNDLE_SYMBOLIC_NAME,
			"The symbolic name of the bundle", SimpleType.STRING);

	/**
	 * The key EVENT, used in {@link #EVENT_ITEM}.
	 */
	String EVENT = "ServiceEvent";

	/**
	 * The item containing the event type. The key is {@link #EVENT} and the
	 * type is {@link SimpleType#INTEGER}
	 */
	Item EVENT_ITEM = new Item(
			EVENT,
			"The eventType of the event: {REGISTERED=1, MODIFIED=2 UNREGISTERING=3}",
			SimpleType.INTEGER);

	/**
	 * The Composite Type that represents a service event. This composite
	 * consists of:
	 * <ul>
	 * <li>{@link #IDENTIFIER}</li>
	 * <li>{@link #OBJECT_CLASS}</li>
	 * <li>{@link #BUNDLE_LOCATION}</li>
	 * <li>{@link #BUNDLE_SYMBOLIC_NAME}</li>
	 * <li>{@link #EVENT}</li>
	 * </ul>
	 */
	CompositeType SERVICE_EVENT_TYPE = Item.compositeType("SERVICE_EVENT",
			"This type encapsulates OSGi service events", IDENTIFIER_ITEM,
			OBJECT_CLASS_ITEM, BUNDLE_IDENTIFIER_ITEM, BUNDLE_LOCATION_ITEM,
			BUNDLE_SYMBOLIC_NAME_ITEM, EVENT_ITEM);

	/**
	 * Answer the list of interfaces that this service implements
	 * 
	 * @param serviceId
	 *            the identifier of the service
	 * @return the list of interfaces
	 * @throws IOException
	 *             if the operation fails
	 * @throws IllegalArgumentException
	 *             if the service indicated does not exist
	 */
	public String[] getObjectClass(long serviceId) throws IOException;

	/**
	 * Answer the bundle identifier of the bundle which registered the service
	 * 
	 * @param serviceId
	 *            the identifier of the service
	 * @return the identifier for the bundle
	 * @throws IOException
	 *             if the operation fails
	 * @throws IllegalArgumentException
	 *             if the service indicated does not exist
	 */
	long getBundleIdentifier(long serviceId) throws IOException;

	/**
	 * Answer the map of properties associated with this service
	 * 
	 * @see JmxConstants#PROPERTIES_TYPE JmxConstants.PROPERTIES_TYPE for the
	 *      details of the TabularType
	 * 
	 * @param serviceId the identifier of the service
	 * @return the table of properties. These include the standard mandatory
	 *         service.id and objectClass properties as defined in the
	 *         {@code org.osgi.framework.Constants} interface
	 * @throws IOException if the operation fails
	 * @throws IllegalArgumentException if the service indicated does not exist
	 */
	TabularData getProperties(long serviceId) throws IOException;

	/**
	 * Answer the service state of the system in tabular form.
	 * 
	 * @see #SERVICES_TYPE SERVICES_TYPE for the details of the TabularType
	 * 
	 * @return the tabular representation of the service state
	 * @throws IOException If the operation fails
	 * @throws IllegalArgumentException if the service indicated does not exist
	 */
	TabularData listServices() throws IOException;

	/**
	 * Answer the list of identifiers of the bundles that use the service
	 * 
	 * @param serviceId
	 *            the identifier of the service
	 * @return the list of bundle identifiers
	 * @throws IOException
	 *             if the operation fails
	 * @throws IllegalArgumentException
	 *             if the service indicated does not exist
	 */
	long[] getUsingBundles(long serviceId) throws IOException;

}
