#region License
/*
* Copyright 2002-2005 the original author or authors.
*
* 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.
*/
#endregion
#region Imports
using System;
using System.Collections;
using System.Reflection;
#endregion
namespace Spring.Objects.Events.Support{
/// <summary>
/// Default implementation of the <see cref="Spring.Objects.Events.IEventRegistry"/>
/// interface.
/// </summary>
/// <author>Griffin Caprio</author>
public class EventRegistry : IEventRegistry
{
private readonly IList _publishers;
/// <summary>
/// Creates a new instance of the EventRegistry class.
/// </summary>
public EventRegistry()
{
_publishers = new ArrayList();
}
/// <summary>
/// The list of event publishers.
/// </summary>
/// <value>The list of event publishers.</value>
protected IList Publishers
{
get { return _publishers; }
}
/// <summary>
/// Adds the input object to the list of publishers.
/// </summary>
/// <remarks>
/// This publishes <b>all</b> events of the source object to any object
/// wishing to subscribe
/// </remarks>
/// <param name="source">The source object to publish.</param>
public virtual void PublishEvents(object source)
{
Publishers.Add(source);
}
/// <summary>
/// Subscribes to <b>all</b> events published, if the subscriber implements
/// compatible handler methods.
/// </summary>
/// <param name="subscriber">The subscriber to use.</param>
public virtual void Subscribe(object subscriber)
{
Subscribe(subscriber, null);
}
/// <summary>
/// Subscribes to published events of all objects of a given type, if the
/// subscriber implements compatible handler methods.
/// </summary>
/// <param name="subscriber">The subscriber to use.</param>
/// <param name="sourceType">
/// The target <see cref="System.Type"/> to subscribe to.
/// </param>
public virtual void Subscribe(object subscriber, Type sourceType)
{
Type currentSubscriberType = subscriber.GetType();
foreach (object currentPublisher in _publishers)
{
if (null == sourceType
|| sourceType.IsAssignableFrom(currentPublisher.GetType()))
{
WireOrUnwireSubscriberToPublisher(
currentPublisher, currentSubscriberType, subscriber, true);
}
}
}
/// <summary>
/// Unsubscribes to <b>all</b> events published, if the subscriber
/// implmenets compatible handler methods.
/// </summary>
/// <param name="subscriber">The subscriber to use</param>
public virtual void Unsubscribe(object subscriber)
{
Unsubscribe(subscriber, null);
}
/// <summary>
/// Unsubscribes to the published events of all objects of a given
/// <see cref="System.Type"/>, if the subscriber implements
/// compatible handler methods.
/// </summary>
/// <param name="subscriber">The subscriber to use.</param>
/// <param name="sourceType">The target <see cref="System.Type"/> to unsubscribe from</param>
public virtual void Unsubscribe(object subscriber, Type sourceType)
{
Type currentSubscriberType = subscriber.GetType();
foreach (object currentPublisher in _publishers)
{
if (null == sourceType
|| sourceType.IsAssignableFrom(currentPublisher.GetType()))
{
WireOrUnwireSubscriberToPublisher(
currentPublisher, currentSubscriberType, subscriber, false);
}
}
}
private static void WireOrUnwireSubscriberToPublisher(
object currentPublisher, Type currentSubscriberType, object subscriber, bool wire)
{
Type currentPublisherType = currentPublisher.GetType();
EventInfo[] events = currentPublisherType.GetEvents();
foreach (EventInfo currentEvent in events)
{
Type eventHandlerType = currentEvent.EventHandlerType;
MethodInfo invoke = eventHandlerType.GetMethod("Invoke");
MethodInfo eventHandler
= EventManipulationUtils.GetMethodInfoMatchingSignature(
invoke, currentSubscriberType);
if (eventHandler != null)
{
if (wire)
{
currentEvent.AddEventHandler(
currentPublisher,
EventManipulationUtils.GetHandlerDelegate(
eventHandlerType, subscriber, eventHandler));
}
else
{
currentEvent.RemoveEventHandler(
currentPublisher,
EventManipulationUtils.GetHandlerDelegate(
eventHandlerType, subscriber, eventHandler));
}
}
}
}
}
}
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