/*
 * Copyright (c) OSGi Alliance (2000, 2013). 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.framework;

import java.util.EventObject;

An event from the Framework describing a bundle lifecycle change.
 BundleEvent objects are delivered to SynchronousBundleListeners and BundleListeners when a change occurs in a bundle's lifecycle. A type code is used to identify the event type for future extendability. 

OSGi Alliance reserves the right to extend the set of types.
Author:
$Id: cd49848213816c4f76541b70be12ac3af7900972 $
See Also:
BundleListener
SynchronousBundleListener
@Immutable
/**
 * An event from the Framework describing a bundle lifecycle change.
 * <p>
 * {@code BundleEvent} objects are delivered to
 * {@code SynchronousBundleListener}s and {@code BundleListener}s when a change
 * occurs in a bundle's lifecycle. A type code is used to identify the event
 * type for future extendability.
 * 
 * <p>
 * OSGi Alliance reserves the right to extend the set of types.
 * 
 * @Immutable
 * @see BundleListener
 * @see SynchronousBundleListener
 * @author $Id: cd49848213816c4f76541b70be12ac3af7900972 $
 */

public class BundleEvent extends EventObject {
	static final long		serialVersionUID	= 4080640865971756012L;
	
Bundle that had a change occur in its lifecycle.
/**
	 * Bundle that had a change occur in its lifecycle.
	 */
	private final Bundle	bundle;

	
Type of bundle lifecycle change.
/**
	 * Type of bundle lifecycle change.
	 */
	private final int		type;

	
The bundle has been installed.
See Also:
installBundle.installBundle(String)/**
	 * The bundle has been installed.
	 * 
	 * @see BundleContext#installBundle(String)
	 */
	public final static int	INSTALLED			= 0x00000001;

	
The bundle has been started.
 The bundle's BundleActivator
start method has been executed if the bundle has a bundle activator class. 
See Also:
Bundle.start()/**
	 * The bundle has been started.
	 * <p>
	 * The bundle's {@link BundleActivator#start(BundleContext) BundleActivator
	 * start} method has been executed if the bundle has a bundle activator
	 * class.
	 * 
	 * @see Bundle#start()
	 */
	public final static int	STARTED				= 0x00000002;

	
The bundle has been stopped.
 The bundle's BundleActivator
stop method has been executed if the bundle has a bundle activator class. 
See Also:
Bundle.stop()/**
	 * The bundle has been stopped.
	 * <p>
	 * The bundle's {@link BundleActivator#stop(BundleContext) BundleActivator
	 * stop} method has been executed if the bundle has a bundle activator
	 * class.
	 * 
	 * @see Bundle#stop()
	 */
	public final static int	STOPPED				= 0x00000004;

	
The bundle has been updated.
See Also:
update.update()/**
	 * The bundle has been updated.
	 * 
	 * @see Bundle#update()
	 */
	public final static int	UPDATED				= 0x00000008;

	
The bundle has been uninstalled.
See Also:
uninstall.uninstall()/**
	 * The bundle has been uninstalled.
	 * 
	 * @see Bundle#uninstall()
	 */
	public final static int	UNINSTALLED			= 0x00000010;

	
The bundle has been resolved.
See Also:
RESOLVED.RESOLVED
Since:
1.3/**
	 * The bundle has been resolved.
	 * 
	 * @see Bundle#RESOLVED
	 * @since 1.3
	 */
	public final static int	RESOLVED			= 0x00000020;

	
The bundle has been unresolved.
See Also:
INSTALLED.INSTALLED
Since:
1.3/**
	 * The bundle has been unresolved.
	 * 
	 * @see Bundle#INSTALLED
	 * @since 1.3
	 */
	public final static int	UNRESOLVED			= 0x00000040;

	
The bundle is about to be activated.
 The bundle's BundleActivator
start method is about to be called if the bundle has a bundle activator class. This event is only delivered to SynchronousBundleListener s. It is not delivered to BundleListeners. 
See Also:
Bundle.start()
Since:
1.3/**
	 * The bundle is about to be activated.
	 * <p>
	 * The bundle's {@link BundleActivator#start(BundleContext) BundleActivator
	 * start} method is about to be called if the bundle has a bundle activator
	 * class. This event is only delivered to {@link SynchronousBundleListener}
	 * s. It is not delivered to {@code BundleListener}s.
	 * 
	 * @see Bundle#start()
	 * @since 1.3
	 */
	public final static int	STARTING			= 0x00000080;

	
The bundle is about to deactivated.
 The bundle's BundleActivator
stop method is about to be called if the bundle has a bundle activator class. This event is only delivered to SynchronousBundleListener s. It is not delivered to BundleListeners. 
See Also:
Bundle.stop()
Since:
1.3/**
	 * The bundle is about to deactivated.
	 * <p>
	 * The bundle's {@link BundleActivator#stop(BundleContext) BundleActivator
	 * stop} method is about to be called if the bundle has a bundle activator
	 * class. This event is only delivered to {@link SynchronousBundleListener}
	 * s. It is not delivered to {@code BundleListener}s.
	 * 
	 * @see Bundle#stop()
	 * @since 1.3
	 */
	public final static int	STOPPING			= 0x00000100;

	
The bundle will be lazily activated.
 The bundle has a lazy activation policy and is waiting to be activated. It is now in the 
STARTING state and has a valid BundleContext. This event is only delivered to SynchronousBundleListeners. It is not delivered to BundleListeners. 
Since:
1.4/**
	 * The bundle will be lazily activated.
	 * <p>
	 * The bundle has a {@link Constants#ACTIVATION_LAZY lazy activation policy}
	 * and is waiting to be activated. It is now in the {@link Bundle#STARTING
	 * STARTING} state and has a valid {@code BundleContext}. This event is only
	 * delivered to {@link SynchronousBundleListener}s. It is not delivered to
	 * {@code BundleListener}s.
	 * 
	 * @since 1.4
	 */
	public final static int	LAZY_ACTIVATION		= 0x00000200;

	
Bundle that was the origin of the event. For install event type, this is
the bundle whose context was used to install the bundle. Otherwise it is
the bundle itself.
Since:
1.6/**
	 * Bundle that was the origin of the event. For install event type, this is
	 * the bundle whose context was used to install the bundle. Otherwise it is
	 * the bundle itself.
	 * 
	 * @since 1.6
	 */
	private final Bundle	origin;

	
Creates a bundle event of the specified type.
Params:
type – The event type.
bundle – The bundle which had a lifecycle change.
origin – The bundle which is the origin of the event. For the event type INSTALLED, this is the bundle whose context was used to install the bundle. Otherwise it is the bundle itself.
Since:
1.6/**
	 * Creates a bundle event of the specified type.
	 * 
	 * @param type The event type.
	 * @param bundle The bundle which had a lifecycle change.
	 * @param origin The bundle which is the origin of the event. For the event
	 *        type {@link #INSTALLED}, this is the bundle whose context was used
	 *        to install the bundle. Otherwise it is the bundle itself.
	 * @since 1.6
	 */
	public BundleEvent(int type, Bundle bundle, Bundle origin) {
		super(bundle);
		if (origin == null) {
			throw new IllegalArgumentException("null origin");
		}
		this.bundle = bundle;
		this.type = type;
		this.origin = origin;
	}

	
Creates a bundle event of the specified type.
Params:
type – The event type.
bundle – The bundle which had a lifecycle change. This bundle is
       used as the origin of the event./**
	 * Creates a bundle event of the specified type.
	 * 
	 * @param type The event type.
	 * @param bundle The bundle which had a lifecycle change. This bundle is
	 *        used as the origin of the event.
	 */
	public BundleEvent(int type, Bundle bundle) {
		super(bundle);
		this.bundle = bundle;
		this.type = type;
		this.origin = bundle;
	}

	
Returns the bundle which had a lifecycle change. This bundle is the
source of the event.
Returns:
The bundle that had a change occur in its lifecycle./**
	 * Returns the bundle which had a lifecycle change. This bundle is the
	 * source of the event.
	 * 
	 * @return The bundle that had a change occur in its lifecycle.
	 */
	public Bundle getBundle() {
		return bundle;
	}

	
Returns the type of lifecyle event. The type values are:

INSTALLED
RESOLVED
LAZY_ACTIVATION
STARTING
STARTED
STOPPING
STOPPED
UPDATED
UNRESOLVED
UNINSTALLED

Returns:
The type of lifecycle event./**
	 * Returns the type of lifecyle event. The type values are:
	 * <ul>
	 * <li>{@link #INSTALLED}</li>
	 * <li>{@link #RESOLVED}</li>
	 * <li>{@link #LAZY_ACTIVATION}</li>
	 * <li>{@link #STARTING}</li>
	 * <li>{@link #STARTED}</li>
	 * <li>{@link #STOPPING}</li>
	 * <li>{@link #STOPPED}</li>
	 * <li>{@link #UPDATED}</li>
	 * <li>{@link #UNRESOLVED}</li>
	 * <li>{@link #UNINSTALLED}</li>
	 * </ul>
	 * 
	 * @return The type of lifecycle event.
	 */
	public int getType() {
		return type;
	}

	
Returns the bundle that was the origin of the event.
 For the event type INSTALLED, this is the bundle whose context was used to install the bundle. Otherwise it is the bundle itself. 
Returns:
The bundle that was the origin of the event.
Since:
1.6/**
	 * Returns the bundle that was the origin of the event.
	 * 
	 * <p>
	 * For the event type {@link #INSTALLED}, this is the bundle whose context
	 * was used to install the bundle. Otherwise it is the bundle itself.
	 * 
	 * @return The bundle that was the origin of the event.
	 * @since 1.6
	 */
	public Bundle getOrigin() {
		return origin;
	}
}