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Posted to commits@directory.apache.org by ak...@apache.org on 2003/12/06 06:29:25 UTC

svn commit: rev 1366 - in incubator/directory/ldap/trunk/eve/frontend/event: impl impl/src impl/src/java impl/src/java/org impl/src/java/org/apache impl/src/java/org/apache/eve impl/src/java/org/apache/eve/event spi spi/src spi/src/java spi/src/java/org spi/src/java/org/apache spi/src/java/org/apache/eve spi/src/java/org/apache/eve/event

Author: akarasulu
Date: Fri Dec  5 21:29:25 2003
New Revision: 1366

Added:
   incubator/directory/ldap/trunk/eve/frontend/event/impl/
   incubator/directory/ldap/trunk/eve/frontend/event/impl/src/
   incubator/directory/ldap/trunk/eve/frontend/event/impl/src/java/
   incubator/directory/ldap/trunk/eve/frontend/event/impl/src/java/org/
   incubator/directory/ldap/trunk/eve/frontend/event/impl/src/java/org/apache/
   incubator/directory/ldap/trunk/eve/frontend/event/impl/src/java/org/apache/eve/
   incubator/directory/ldap/trunk/eve/frontend/event/impl/src/java/org/apache/eve/event/
   incubator/directory/ldap/trunk/eve/frontend/event/impl/src/java/org/apache/eve/event/EventRouterImpl.java
   incubator/directory/ldap/trunk/eve/frontend/event/spi/
   incubator/directory/ldap/trunk/eve/frontend/event/spi/src/
   incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/
   incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/
   incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/
   incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/eve/
   incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/eve/event/
   incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/eve/event/EventRouter.java
   incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/eve/event/Filter.java
   incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/eve/event/Subscription.java
Log:
Adding the event router module.


Added: incubator/directory/ldap/trunk/eve/frontend/event/impl/src/java/org/apache/eve/event/EventRouterImpl.java
==============================================================================
--- (empty file)
+++ incubator/directory/ldap/trunk/eve/frontend/event/impl/src/java/org/apache/eve/event/EventRouterImpl.java	Fri Dec  5 21:29:25 2003
@@ -0,0 +1,199 @@
+/*
+
+ ============================================================================
+                   The Apache Software License, Version 1.1
+ ============================================================================
+
+ Copyright (C) 1999-2002 The Apache Software Foundation. All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without modifica-
+ tion, are permitted provided that the following conditions are met:
+
+ 1. Redistributions of  source code must  retain the above copyright  notice,
+    this list of conditions and the following disclaimer.
+
+ 2. Redistributions in binary form must reproduce the above copyright notice,
+    this list of conditions and the following disclaimer in the documentation
+    and/or other materials provided with the distribution.
+
+ 3. The end-user documentation included with the redistribution, if any, must
+    include  the following  acknowledgment:  "This product includes  software
+    developed  by the  Apache Software Foundation  (http://www.apache.org/)."
+    Alternately, this  acknowledgment may  appear in the software itself,  if
+    and wherever such third-party acknowledgments normally appear.
+
+ 4. The names "Eve Directory Server", "Apache Directory Project", "Apache Eve" 
+	and "Apache Software Foundation"  must not be used to endorse or promote
+    products derived  from this  software without  prior written
+    permission. For written permission, please contact apache@apache.org.
+
+ 5. Products  derived from this software may not  be called "Apache", nor may
+    "Apache" appear  in their name,  without prior written permission  of the
+    Apache Software Foundation.
+
+ THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+ INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ FITNESS  FOR A PARTICULAR  PURPOSE ARE  DISCLAIMED.  IN NO  EVENT SHALL  THE
+ APACHE SOFTWARE  FOUNDATION  OR ITS CONTRIBUTORS  BE LIABLE FOR  ANY DIRECT,
+ INDIRECT, INCIDENTAL, SPECIAL,  EXEMPLARY, OR CONSEQUENTIAL  DAMAGES (INCLU-
+ DING, BUT NOT LIMITED TO, PROCUREMENT  OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ OF USE, DATA, OR  PROFITS; OR BUSINESS  INTERRUPTION)  HOWEVER CAUSED AND ON
+ ANY  THEORY OF LIABILITY,  WHETHER  IN CONTRACT,  STRICT LIABILITY,  OR TORT
+ (INCLUDING  NEGLIGENCE OR  OTHERWISE) ARISING IN  ANY WAY OUT OF THE  USE OF
+ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ This software  consists of voluntary contributions made  by many individuals
+ on  behalf of the Apache Software  Foundation. For more  information on the
+ Apache Software Foundation, please see <http://www.apache.org/>.
+
+*/
+package org.apache.eve.event ;
+
+
+import java.util.Set ;
+import java.util.HashSet ;
+import java.util.Iterator ;
+import java.util.EventObject ;
+
+
+/**
+ * An synchronous implementation of the event router / notification pattern.
+ *
+ * @author <a href="mailto:aok123@bellsouth.net">Alex Karasulu</a>
+ * @author $Author$
+ * @version $Revision$
+ */
+public class EventRouterImpl implements EventRouter
+{
+    /** the set of subscriptions made with this router */
+    private Set m_subscriptions = new HashSet() ;
+    
+    
+    /**
+     * @see org.apache.eve.event.EventRouter#subscribe(java.lang.Class, 
+     * org.apache.eve.event.Filter, org.apache.eve.event.Subscriber)
+     */
+    public void subscribe( Class a_type, Filter a_filter,
+						   Subscriber a_subscriber )
+    {
+		if ( ! EventObject.class.isAssignableFrom( a_type ) ) 
+		{
+			throw new IllegalArgumentException( "Invalid event class: " 
+					+ a_type.getName() ) ;
+		}
+
+		Subscription l_subscription = 
+        	new Subscription( a_type, a_filter, a_subscriber ) ;
+
+		if ( ! m_subscriptions.contains( l_subscription ) )
+		{
+		    synchronized ( m_subscriptions )
+		    {
+		        m_subscriptions.add( l_subscription ) ;
+		    }
+		}
+    }
+
+    
+    /**
+     * @see org.apache.eve.event.EventRouter#unsubscribe(
+     * org.apache.eve.event.Subscriber)
+     */
+    public void unsubscribe( Subscriber a_subscriber )
+    {
+        Iterator l_list = m_subscriptions.iterator() ;
+        
+		synchronized ( m_subscriptions )
+		{
+	        while ( l_list.hasNext() )
+	        {
+	            Subscription l_subscription = ( Subscription ) l_list.next() ;
+	            if ( a_subscriber == l_subscription.getSubscriber() )
+	            {
+	                l_list.remove() ;
+	            }
+	        }
+		}
+    }
+
+
+	/**
+	 * (non-Javadoc)
+	 * @see org.apache.eve.event.EventRouter#unsubscribe(java.lang.Class, 
+	 * org.apache.eve.event.Subscriber)
+	 */
+	public void unsubscribe( Class a_type, Subscriber a_subscriber )
+	{
+		Iterator l_list = m_subscriptions.iterator() ;
+        
+		synchronized ( m_subscriptions )
+		{
+			while ( l_list.hasNext() )
+			{
+				Subscription l_subscription = ( Subscription ) l_list.next() ;
+				if ( a_subscriber == l_subscription.getSubscriber()
+				  && a_type.equals( l_subscription.getType() ) )
+				{
+					l_list.remove() ;
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * (non-Javadoc)
+	 * @see org.apache.eve.event.EventRouter#unsubscribe(java.lang.Class, 
+	 * org.apache.eve.event.Subscriber)
+	 */
+	public void unsubscribe( Class a_type, Filter a_filter, 
+							 Subscriber a_subscriber )
+	{
+		if ( ! EventObject.class.isAssignableFrom( a_type ) ) 
+		{
+			throw new IllegalArgumentException( "Invalid event class: " 
+			        + a_type.getName() ) ;
+		}
+		
+		final Subscription l_subscription = new Subscription( a_type, a_filter, 
+		        a_subscriber ) ;
+        
+		synchronized ( m_subscriptions )
+		{
+			m_subscriptions.remove( l_subscription ) ;
+		}
+	}
+
+
+    /**
+     * (non-Javadoc)
+     * @see org.apache.eve.event.EventRouter#publish(org.apache.eve.event.Event)
+     */
+    public void publish( EventObject a_event ) 
+    {
+        final Subscription [] l_subscriptions ;
+        
+        synchronized ( m_subscriptions )
+        {
+            l_subscriptions = ( Subscription [] ) m_subscriptions
+            	.toArray( new Subscription [ m_subscriptions.size() ] ) ;
+        }
+
+        for ( int ii = 0; ii < l_subscriptions.length; ii++ )
+        {
+            boolean isAssignable = l_subscriptions[ii].getType()
+            	.isAssignableFrom( a_event.getClass() ) ;
+            
+            if ( ! isAssignable )
+            {
+                continue ;
+            }
+            
+            if ( l_subscriptions[ii].getFilter() != null && 
+                 l_subscriptions[ii].getFilter().apply( a_event ) )  
+			{
+				l_subscriptions[ii].getSubscriber().inform( a_event ) ;
+			}
+        }
+    }
+}

Added: incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/eve/event/EventRouter.java
==============================================================================
--- (empty file)
+++ incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/eve/event/EventRouter.java	Fri Dec  5 21:29:25 2003
@@ -0,0 +1,100 @@
+/*
+
+ ============================================================================
+                   The Apache Software License, Version 1.1
+ ============================================================================
+
+ Copyright (C) 1999-2002 The Apache Software Foundation. All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without modifica-
+ tion, are permitted provided that the following conditions are met:
+
+ 1. Redistributions of  source code must  retain the above copyright  notice,
+    this list of conditions and the following disclaimer.
+
+ 2. Redistributions in binary form must reproduce the above copyright notice,
+    this list of conditions and the following disclaimer in the documentation
+    and/or other materials provided with the distribution.
+
+ 3. The end-user documentation included with the redistribution, if any, must
+    include  the following  acknowledgment:  "This product includes  software
+    developed  by the  Apache Software Foundation  (http://www.apache.org/)."
+    Alternately, this  acknowledgment may  appear in the software itself,  if
+    and wherever such third-party acknowledgments normally appear.
+
+ 4. The names "Eve Directory Server", "Apache Directory Project", "Apache Eve" 
+	and "Apache Software Foundation"  must not be used to endorse or promote
+    products derived  from this  software without  prior written
+    permission. For written permission, please contact apache@apache.org.
+
+ 5. Products  derived from this software may not  be called "Apache", nor may
+    "Apache" appear  in their name,  without prior written permission  of the
+    Apache Software Foundation.
+
+ THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+ INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ FITNESS  FOR A PARTICULAR  PURPOSE ARE  DISCLAIMED.  IN NO  EVENT SHALL  THE
+ APACHE SOFTWARE  FOUNDATION  OR ITS CONTRIBUTORS  BE LIABLE FOR  ANY DIRECT,
+ INDIRECT, INCIDENTAL, SPECIAL,  EXEMPLARY, OR CONSEQUENTIAL  DAMAGES (INCLU-
+ DING, BUT NOT LIMITED TO, PROCUREMENT  OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ OF USE, DATA, OR  PROFITS; OR BUSINESS  INTERRUPTION)  HOWEVER CAUSED AND ON
+ ANY  THEORY OF LIABILITY,  WHETHER  IN CONTRACT,  STRICT LIABILITY,  OR TORT
+ (INCLUDING  NEGLIGENCE OR  OTHERWISE) ARISING IN  ANY WAY OUT OF THE  USE OF
+ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ This software  consists of voluntary contributions made  by many individuals
+ on  behalf of the Apache Software  Foundation. For more  information on the
+ Apache Software Foundation, please see <http://www.apache.org/>.
+
+*/
+package org.apache.eve.event ;
+
+
+import java.util.EventObject ;
+
+
+/**
+ * Event service based on an exact version of the event notifier pattern found
+ * <a href="http://members.ispwest.com/jeffhartkopf/notifier/">here</a>.
+ * 
+ * @author <a href="mailto:aok123@bellsouth.net">Alex Karasulu</a>
+ * @author $Author$
+ * @version $Revision$
+ */
+public interface EventRouter
+{
+    /** Avalon compliant service interface role */
+    String ROLE = EventRouter.class.getName() ;
+    
+	/**
+	 * Subscribes an event subscriber.
+	 * 
+	 * @param a_type an event type enumeration value
+	 * @param a_filter an event filter if any to apply
+	 * @param a_subscriber the Subscriber to subscribe
+	 */
+	void subscribe( Class a_type, Filter a_filter, 
+					Subscriber a_subscriber ) ;
+    
+	/**
+	 * Unsubscribes an event subscriber.
+	 * 
+	 * @param a_subscriber the Subscriber to unsubscribe
+	 */
+	void unsubscribe( Subscriber a_subscriber ) ;
+    
+	/**
+	 * Unsubscribes an event subscriber.
+	 * 
+	 * @param a_subscriber the Subscriber to unsubscribe
+	 */
+	void unsubscribe( Class a_type, Subscriber a_subscriber ) ;
+    
+    /**
+     * Fires an event synchronously in the thread of the caller to all 
+     * subscribers registered for a specific event type.
+     * 
+     * @param a_event the event to publish
+     */
+    void publish( EventObject a_event ) ;
+}

Added: incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/eve/event/Filter.java
==============================================================================
--- (empty file)
+++ incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/eve/event/Filter.java	Fri Dec  5 21:29:25 2003
@@ -0,0 +1,73 @@
+/*
+
+ ============================================================================
+                   The Apache Software License, Version 1.1
+ ============================================================================
+
+ Copyright (C) 1999-2002 The Apache Software Foundation. All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without modifica-
+ tion, are permitted provided that the following conditions are met:
+
+ 1. Redistributions of  source code must  retain the above copyright  notice,
+    this list of conditions and the following disclaimer.
+
+ 2. Redistributions in binary form must reproduce the above copyright notice,
+    this list of conditions and the following disclaimer in the documentation
+    and/or other materials provided with the distribution.
+
+ 3. The end-user documentation included with the redistribution, if any, must
+    include  the following  acknowledgment:  "This product includes  software
+    developed  by the  Apache Software Foundation  (http://www.apache.org/)."
+    Alternately, this  acknowledgment may  appear in the software itself,  if
+    and wherever such third-party acknowledgments normally appear.
+
+ 4. The names "Eve Directory Server", "Apache Directory Project", "Apache Eve" 
+	and "Apache Software Foundation"  must not be used to endorse or promote
+    products derived  from this  software without  prior written
+    permission. For written permission, please contact apache@apache.org.
+
+ 5. Products  derived from this software may not  be called "Apache", nor may
+    "Apache" appear  in their name,  without prior written permission  of the
+    Apache Software Foundation.
+
+ THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+ INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ FITNESS  FOR A PARTICULAR  PURPOSE ARE  DISCLAIMED.  IN NO  EVENT SHALL  THE
+ APACHE SOFTWARE  FOUNDATION  OR ITS CONTRIBUTORS  BE LIABLE FOR  ANY DIRECT,
+ INDIRECT, INCIDENTAL, SPECIAL,  EXEMPLARY, OR CONSEQUENTIAL  DAMAGES (INCLU-
+ DING, BUT NOT LIMITED TO, PROCUREMENT  OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ OF USE, DATA, OR  PROFITS; OR BUSINESS  INTERRUPTION)  HOWEVER CAUSED AND ON
+ ANY  THEORY OF LIABILITY,  WHETHER  IN CONTRACT,  STRICT LIABILITY,  OR TORT
+ (INCLUDING  NEGLIGENCE OR  OTHERWISE) ARISING IN  ANY WAY OUT OF THE  USE OF
+ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ This software  consists of voluntary contributions made  by many individuals
+ on  behalf of the Apache Software  Foundation. For more  information on the
+ Apache Software Foundation, please see <http://www.apache.org/>.
+
+*/
+package org.apache.eve.event ;
+
+
+import java.util.EventObject ;
+
+
+/**
+ * A filter in the event router is used to further prune the subscriber's 
+ * interest list.
+ *
+ * @author <a href="mailto:aok123@bellsouth.net">Alex Karasulu</a>
+ * @author $Author$
+ * @version $Revision$
+ */
+public interface Filter
+{
+    /**
+     * Determines whether or not to inform a subscriber of an event.
+     * 
+     * @param a_event the event to test 
+     * @return true if the event can be sent, false if it cannot
+     */
+    boolean apply( EventObject a_event ) ;
+}

Added: incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/eve/event/Subscription.java
==============================================================================
--- (empty file)
+++ incubator/directory/ldap/trunk/eve/frontend/event/spi/src/java/org/apache/eve/event/Subscription.java	Fri Dec  5 21:29:25 2003
@@ -0,0 +1,186 @@
+/*
+
+ ============================================================================
+                   The Apache Software License, Version 1.1
+ ============================================================================
+
+ Copyright (C) 1999-2002 The Apache Software Foundation. All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without modifica-
+ tion, are permitted provided that the following conditions are met:
+
+ 1. Redistributions of  source code must  retain the above copyright  notice,
+    this list of conditions and the following disclaimer.
+
+ 2. Redistributions in binary form must reproduce the above copyright notice,
+    this list of conditions and the following disclaimer in the documentation
+    and/or other materials provided with the distribution.
+
+ 3. The end-user documentation included with the redistribution, if any, must
+    include  the following  acknowledgment:  "This product includes  software
+    developed  by the  Apache Software Foundation  (http://www.apache.org/)."
+    Alternately, this  acknowledgment may  appear in the software itself,  if
+    and wherever such third-party acknowledgments normally appear.
+
+ 4. The names "Eve Directory Server", "Apache Directory Project", "Apache Eve" 
+	and "Apache Software Foundation"  must not be used to endorse or promote
+    products derived  from this  software without  prior written
+    permission. For written permission, please contact apache@apache.org.
+
+ 5. Products  derived from this software may not  be called "Apache", nor may
+    "Apache" appear  in their name,  without prior written permission  of the
+    Apache Software Foundation.
+
+ THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+ INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ FITNESS  FOR A PARTICULAR  PURPOSE ARE  DISCLAIMED.  IN NO  EVENT SHALL  THE
+ APACHE SOFTWARE  FOUNDATION  OR ITS CONTRIBUTORS  BE LIABLE FOR  ANY DIRECT,
+ INDIRECT, INCIDENTAL, SPECIAL,  EXEMPLARY, OR CONSEQUENTIAL  DAMAGES (INCLU-
+ DING, BUT NOT LIMITED TO, PROCUREMENT  OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ OF USE, DATA, OR  PROFITS; OR BUSINESS  INTERRUPTION)  HOWEVER CAUSED AND ON
+ ANY  THEORY OF LIABILITY,  WHETHER  IN CONTRACT,  STRICT LIABILITY,  OR TORT
+ (INCLUDING  NEGLIGENCE OR  OTHERWISE) ARISING IN  ANY WAY OUT OF THE  USE OF
+ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ This software  consists of voluntary contributions made  by many individuals
+ on  behalf of the Apache Software  Foundation. For more  information on the
+ Apache Software Foundation, please see <http://www.apache.org/>.
+
+*/
+package org.apache.eve.event ;
+
+
+/**
+ * A subscription bean.
+ *
+ * @author <a href="mailto:aok123@bellsouth.net">Alex Karasulu</a>
+ * @author $Author$
+ * @version $Revision$
+ */
+public class Subscription
+{
+    /** the filter if any used to filter out events */
+	private final Filter m_filter ; 
+	/** the event class */
+	private final Class m_type ; 
+	/** the subscriber */
+	private final Subscriber m_subscriber ; 
+
+	
+	/**
+	 * Creates a subscription for a type of event using a filter and a 
+	 * subscriber.
+	 * 
+	 * @param a_type the class of event to be informed on
+	 * @param a_filter the Filter to use weed out unwanted events
+	 * @param a_subscriber the subscriber to deliever the event to
+	 */
+	public Subscription( Class a_type, Filter a_filter, 
+						 Subscriber a_subscriber ) 
+	{ 
+	    m_type = a_type ;
+	    m_filter = a_filter ;
+	    m_subscriber = a_subscriber ;
+	}
+	
+	
+	/**
+	 * Get the event class/type
+	 *
+	 * @return the event class/type
+	 */
+	public Class getType() 
+	{
+		return m_type ;
+	}
+	
+
+	/**
+	 * Get the filter used with this subscription.
+	 *
+	 * @return  The filter
+	 */
+	public Filter getFilter() 
+	{
+		return m_filter ;
+	}
+
+	
+	/**
+	 * Get the subscriber.
+	 *
+	 * @return the subscriber
+	 */
+	public Subscriber getSubscriber() 
+	{
+		return m_subscriber ;
+	}
+
+	
+	/**
+	 * Compare two Subscriptions to each other.
+	 *
+	 * @param a_obj the object to compare this Subscription to
+	 * @return <code>true</code> if the two Subscription objects are the same
+	 */
+	public boolean equals( Object a_obj ) 
+	{
+		if ( this == a_obj ) 
+		{
+		    return true ;
+		}
+		
+		if ( ! ( a_obj instanceof Subscription ) ) 
+		{ 
+		    return false ;
+		}
+
+		final Subscription l_subscription = ( Subscription ) a_obj ;
+
+		if ( ! m_type.equals( l_subscription.getType() ) )
+		{    
+		    return false ;
+		}
+		
+		if ( m_filter != null )
+		{
+		    if ( l_subscription.getFilter() == null )
+		    {
+		        return false ;
+		    }
+		    
+		    if ( ! m_filter.equals( l_subscription.getFilter() ) )
+		    {    
+		        return false ;
+		    }
+		}
+		
+		if ( ! m_subscriber.equals( l_subscription.getSubscriber() ) ) 
+		{
+		    return false ;
+		}
+
+		return true ;
+	}
+	
+
+	/**
+	 * Get the hashcode (used in HashMaps).
+	 *
+	 * hashCode = 37 * (37 * (629 + event.hashCode()) + filter.hashCode())
+	 *            + subscriber.hashCode()
+	 * 
+	 * This method was borrowed from Berin Loritsch.
+	 * 
+	 * @return the hashCode value
+	 */
+	public int hashCode() 
+	{
+		int l_result = 17 ;
+		l_result = 37 * l_result + m_type.hashCode() ;
+		l_result = 37 * l_result + 
+			( m_filter != null ? m_filter.hashCode() : 0 ) ;
+		l_result = 37 * l_result + m_subscriber.hashCode() ;
+		return l_result ;
+	}
+}