/*************************************************************************
*
* ADOBE CONFIDENTIAL
* __________________
*
* [2002] - [2007] Adobe Systems Incorporated
* All Rights Reserved.
*
* NOTICE: All information contained herein is, and remains
* the property of Adobe Systems Incorporated and its suppliers,
* if any. The intellectual and technical concepts contained
* herein are proprietary to Adobe Systems Incorporated
* and its suppliers and may be covered by U.S. and Foreign Patents,
* patents in process, and are protected by trade secret or copyright law.
* Dissemination of this information or reproduction of this material
* is strictly forbidden unless prior written permission is obtained
* from Adobe Systems Incorporated.
**************************************************************************/
package flex.messaging;
import flex.messaging.client.FlexClient;
import flex.messaging.client.FlexClientListener;
import flex.messaging.log.LogCategories;
import flex.messaging.messages.Message;
import flex.messaging.util.TimeoutAbstractObject;
import java.security.Principal;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.concurrent.CopyOnWriteArrayList;
/**
* The base for FlexSession implementations.
*/
public abstract class FlexSession extends TimeoutAbstractObject implements FlexClientListener, MessageClientListener
{
//--------------------------------------------------------------------------
//
// Public Static Variables
//
//--------------------------------------------------------------------------
/**
* Log category for FlexSession related messages.
*/
public static final String FLEX_SESSION_LOG_CATEGORY = LogCategories.ENDPOINT_FLEXSESSION;
//--------------------------------------------------------------------------
//
// Private Static Variables
//
//--------------------------------------------------------------------------
/**
* The set of session created listeners to notify upon a new session creation.
*/
private static final CopyOnWriteArrayList createdListeners = new CopyOnWriteArrayList();
/**
* Error string constants.
*/
private static final int FLEX_SESSION_INVALIDATED = 10019;
//--------------------------------------------------------------------------
//
// Constructor
//
//--------------------------------------------------------------------------
/**
* @exclude
* Constructs a new FlexSession instance.
*
*/
public FlexSession()
{
}
//--------------------------------------------------------------------------
//
// Static Methods
//
//--------------------------------------------------------------------------
/**
* Adds a session created listener that will be notified when new sessions
* are created.
*
* @see flex.messaging.FlexSessionListener
*
* @param listener The listener to add.
*/
public static void addSessionCreatedListener(FlexSessionListener listener)
{
if (listener != null)
createdListeners.addIfAbsent(listener);
}
/**
* Removes a session created listener.
*
* @see flex.messaging.FlexSessionListener
*
* @param listener The listener to remove.
*/
public static void removeSessionCreatedListener(FlexSessionListener listener)
{
if (listener != null)
createdListeners.remove(listener);
}
//--------------------------------------------------------------------------
//
// Variables
//
//--------------------------------------------------------------------------
/**
* Instance level lock to sync for state changes.
*/
protected final Object lock = new Object();
/**
* The attributes associated with this session.
*/
private HashMap attributes;
/**
* Registered attribute listeners for the session.
*/
private volatile CopyOnWriteArrayList attributeListeners;
/**
* Flag indicating whether creation notification has been completed.
*/
private boolean creationNotified;
/**
* The set of session destroy listeners to notify when the session is destroyed.
*/
private volatile CopyOnWriteArrayList destroyedListeners;
/**
* The associated FlexClients.
*/
private final CopyOnWriteArrayList<FlexClient> flexClients = new CopyOnWriteArrayList<FlexClient>();
/**
* Flag used to break cycles during invalidation.
*/
private boolean invalidating;
/**
* List of associated MessageClients created while this session was active (thread local).
*/
private volatile CopyOnWriteArrayList messageClients;
/**
* Storage for remote credentials associated with the session; used by the HTTPProxyService
* when requests are made to a secured remote endpoint.
*/
private volatile Map remoteCredentials;
/**
* Flag indicated whether the session has been invalidated/destroyed.
*/
protected boolean valid = true;
//--------------------------------------------------------------------------
//
// Properties
//
//--------------------------------------------------------------------------
//----------------------------------
// asyncPollMap
//----------------------------------
/**
* @exclude
* Used internally to manage async long-polls; not for public use.
*
* A map of endpoint to async poll objects that keeps track of what
* client is parked on a long-poll with what endpoint.
* We only want an endpoint to have a single connection to a client.
* Normally, the server leaves an async long-poll in place until
* data arrives to push to the client or a timeout is reached.
* However, if two or more browser tabs/windows are sharing the same server session and are both attempting
* async long-polling, we alternate their parked requests to avoid locking up the browser process by holding too many
* Http connections open at once.
* This also aids with closing out 'orphaned' long polls following a browser page reload.
* Generically typed as <code>Object</code>; using this reference is left up to async poll
* implementation code.
*/
public volatile HashMap<String, FlexClient.AsyncPollWithTimeout> asyncPollMap;
//----------------------------------
// principal
//----------------------------------
/**
* The principal associated with the session.
*/
private Principal userPrincipal;
/**
* This method should be called on FlexContext and not on this class. Keeping
* this method for backwards compatibility. This method will produce
* correct results when perClientAuthentication is false. However, it will
* not return correct results when perClientAuthentication is true.
*
* Returns the principal associated with the session. If the client has not
* authenticated the principal will be null.
*
* @return The principal associated with the session.
*/
public Principal getUserPrincipal()
{
synchronized (lock)
{
checkValid();
return userPrincipal;
}
}
/**
* This method should be called on FlexContext and not on this class. Keeping
* this method for backwards compatibility. Calling this when perClientAuthentication
* is true will not correctly set the UserPrincipal.
*
* @param userPrincipal The principal to associate with the session.
*/
public void setUserPrincipal(Principal userPrincipal)
{
synchronized (lock)
{
checkValid();
this.userPrincipal = userPrincipal;
}
}
//----------------------------------
// canStream
//----------------------------------
/**
* @exclude
* Used internally by streaming endpoints to enforce session level streaming
* connection limits; not for public use.
* This flag is volatile to allow for consistent reads across thread without
* needing to pay the cost for a synchronized lock for each read.
*/
public volatile boolean canStream = true;
//----------------------------------
// maxConnectionsPerSession
//----------------------------------
/**
* @exclude
* Used internally by streaming and long polling endpoints to enforce session
* level streaming connection limits; not for public use.
*/
public int maxConnectionsPerSession = 1;
//----------------------------------
// streamingClientsCount
//----------------------------------
/**
* @exclude
* Used internally by streaming and long polling endpoints to enforce
* session level streaming connection limits; not for public use.
*
* Some browsers put limits on the number of connections per session. For
* example, Firefox has network.http.max-connections-per-server=8 limit which
* limits the number of streaming connections per session to 7. Similarly,
* IE has a limit of 2 per session.
*
* This variable is used by streaming and long polling endpoint to keep
* track of open connections per session and disallow them when needed.
*
*/
public int streamingConnectionsCount;
//----------------------------------
// useSmallMessages
//----------------------------------
/**
* @exclude
*/
private boolean useSmallMessages;
/**
* @exclude
* Determines whether the server can attempt to send small messages
* for those messages that have a small form. This setting can be overridden
* by an endpoint's enableSmallMessages switch which controls whether
* small messages should be sent, even if they are supported.
*
* The default is false.
*/
public boolean useSmallMessages()
{
return useSmallMessages;
}
/**
* @exclude
*/
public void setUseSmallMessages(boolean value)
{
useSmallMessages = value;
}
//----------------------------------
// waitMonitor
//----------------------------------
/**
* @exclude
* Used internally to manage wait()-based long-polls; not for public use.
*
* This is the monitor that a request handling thread associated with this
* FlexSession is waiting on. Normally, the waiting request handling thread will wait until
* a new message arrives that can be returned in a poll response or its wait interval times out.
* This also aids with closing out 'orphaned' long polls following a browser page reload.
*/
public volatile HashMap<String, FlexClient.EndpointQueue> waitMonitor;
//--------------------------------------------------------------------------
//
// Methods
//
//--------------------------------------------------------------------------
/**
* Adds a session attribute listener that will be notified when an
* attribute is added, removed or changed.
*
* @param listener The listener to add.
*/
public void addSessionAttributeListener(FlexSessionAttributeListener listener)
{
if (listener != null)
{
checkValid();
if (attributeListeners == null)
{
synchronized (lock)
{
if (attributeListeners == null)
attributeListeners = new CopyOnWriteArrayList();
}
}
attributeListeners.addIfAbsent(listener);
}
}
/**
* Adds a session destroy listener that will be notified when the session
* is destroyed. Session destroy listeners are notified after all attributes
* have been unbound from the session and any FlexSessionBindingListeners
* and FlexSessionAttributeListeners have been notified.
*
* @see flex.messaging.FlexSessionListener
*
* @param listener The listener to add.
*/
public void addSessionDestroyedListener(FlexSessionListener listener)
{
if (listener != null)
{
checkValid();
if (destroyedListeners == null)
{
synchronized (lock)
{
if (destroyedListeners == null)
destroyedListeners = new CopyOnWriteArrayList();
}
}
destroyedListeners.addIfAbsent(listener);
}
}
/**
* Returns the attribute bound to the specified name in the session, or null
* if no attribute is bound under the name.
*
* @param name The name the target attribute is bound to.
* @return The attribute bound to the specified name.
*/
public Object getAttribute(String name)
{
synchronized (lock)
{
checkValid();
return (attributes == null) ? null : attributes.get(name);
}
}
/**
* Returns a snapshot of the names of all attributes bound to the session.
*
* @return A snapshot of the names of all attributes bound to the session.
*/
public Enumeration getAttributeNames()
{
synchronized (lock)
{
checkValid();
if (attributes == null)
return Collections.enumeration(Collections.EMPTY_LIST);
// Return a copy so we do not run into concurrent modification problems if
// someone adds to the attributes while iterating through the returned enumeration.
return Collections.enumeration(new ArrayList(attributes.keySet()));
}
}
/**
* @exclude
* Implements MessageClientListener.
* Handling created events is a no-op.
*
* @messageClient The new MessageClient.
*/
public void messageClientCreated(MessageClient messageClient) {}
/**
* @exclude
* Implements MessageClientListener.
* Notification that an associated MessageClient was destroyed.
*
* @param messageClient The MessageClient that was destroyed.
*/
public void messageClientDestroyed(MessageClient messageClient)
{
unregisterMessageClient(messageClient);
}
/**
* @exclude
* FlexClient invokes this to determine whether the session can be used to push messages
* to the client.
*
* @return true if the FlexSession supports direct push; otherwise false (polling is assumed).
*/
public abstract boolean isPushSupported();
/**
* @exclude
* FlexClient invokes this to push a message to a remote client.
*
* @param message The message to push.
*/
public void push(Message message)
{
throw new UnsupportedOperationException("Push not supported.");
}
/**
* Removes the attribute bound to the specified name in the session.
*
* @param name The name of the attribute to remove.
*/
public void removeAttribute(String name)
{
Object value; // Used for event dispatch after the attribute is removed.
synchronized (lock)
{
checkValid(); // Re-enters lock but should be fast because we're already holding it.
value = (attributes != null) ? attributes.remove(name) : null;
}
// If no value was bound under this name it's a no-op.
if (value == null)
return;
notifyAttributeUnbound(name, value);
notifyAttributeRemoved(name, value);
}
/**
* Removes a session attribute listener.
*
* @param listener The listener to remove.
*/
public void removeSessionAttributeListener(FlexSessionAttributeListener listener)
{
// No need to check validity; removing a listener is always ok.
if (listener != null && attributeListeners != null)
attributeListeners.remove(listener);
}
/**
* Removes a session destroy listener.
*
* @see flex.messaging.FlexSessionListener
*
* @param listener The listener to remove.
*/
public void removeSessionDestroyedListener(FlexSessionListener listener)
{
// No need to check validity; removing a listener is always ok.
if (listener != null && destroyedListeners != null)
destroyedListeners.remove(listener);
}
/**
* Binds an attribute value to the session under the specified name.
*
* @param name The name to bind the attribute under.
* @param value The value of the attribute.
*/
public void setAttribute(String name, Object value)
{
// Null value is the same as removeAttribute().
if (value == null)
{
removeAttribute(name);
return;
}
Object oldValue; // Used to determine which events to dispatch after the set is performed.
// Only synchronize for the attribute mutation; event dispatch doesn't require it.
synchronized (lock)
{
checkValid(); // Re-enters lock but should be fast because we're already holding it.
if (attributes == null)
attributes = new HashMap();
oldValue = attributes.put(name, value);
}
if (oldValue == null)
{
notifyAttributeBound(name, value);
notifyAttributeAdded(name, value);
}
else
{
notifyAttributeUnbound(name, oldValue);
notifyAttributeReplaced(name, oldValue);
notifyAttributeBound(name, value);
}
}
/**
* Stores remote credentials in the session for proxied calls to remote systems.
*
* @param credentials The remote credentials.
*/
public void putRemoteCredentials(FlexRemoteCredentials credentials)
{
if (credentials != null)
{
// We only need to hold the lock to lazy-init the remoteCredentials variable.
if (remoteCredentials == null)
{
synchronized (lock)
{
// Init size to 4 because that's the number of shipping service types
// (messaging, remoting, proxy, data management).
if (remoteCredentials == null)
remoteCredentials = new HashMap(4);
}
}
synchronized (remoteCredentials)
{
Map serviceMap = (Map)remoteCredentials.get(credentials.getService());
if (serviceMap == null)
{
// Init size to half the normal number of buckets; most services won't have a large
// number of destinations with remote credentials.
serviceMap = new HashMap(7);
remoteCredentials.put(credentials.getService(), serviceMap);
}
serviceMap.put(credentials.getDestination(), credentials);
}
}
}
/**
* Returns the remote credentials stored in the session for the specified service destination.
*
* @param serviceId The service id.
* @param destinationId The destination id.
* @return The stored remote credentials for the specified service destination.
*/
public FlexRemoteCredentials getRemoteCredentials(String serviceId, String destinationId)
{
if (serviceId != null && destinationId != null)
{
if (remoteCredentials == null)
return null;
synchronized (remoteCredentials)
{
Map serviceMap = (Map)remoteCredentials.get(serviceId);
return (serviceMap != null) ? (FlexRemoteCredentials)serviceMap.get(destinationId) : null;
}
}
return null;
}
/**
* Clears any stored remote credentials from the session for the specified service destination.
*
* @param serviceId The service Id.
* @param destinationId The destination Id.
*/
public void clearRemoteCredentials(String serviceId, String destinationId)
{
if (serviceId != null && destinationId != null)
{
if (remoteCredentials == null)
return;
synchronized (remoteCredentials)
{
Map serviceMap = (Map)remoteCredentials.get(serviceId);
if (serviceMap != null)
{
serviceMap.put(destinationId, null);
}
}
}
}
/**
* Invalidates the FlexSession.
*/
public void invalidate()
{
synchronized (lock)
{
if (!valid || invalidating)
return; // Already shutting down.
invalidating = true; // This thread gets to shut the FlexSession down.
cancelTimeout();
}
// Unregister all FlexClients.
if (!flexClients.isEmpty())
{
for (FlexClient flexClient : flexClients)
unregisterFlexClient(flexClient);
}
// Invalidate associated MessageClient subscriptions.
if (messageClients != null && !messageClients.isEmpty())
{
for (Iterator iter = messageClients.iterator(); iter.hasNext();)
{
MessageClient messageClient = (MessageClient)iter.next();
messageClient.removeMessageClientDestroyedListener(this);
messageClient.invalidate();
}
messageClients.clear();
}
// Notify sessionDestroyed listeners that the session is being invalidated.
if (destroyedListeners != null && !destroyedListeners.isEmpty())
{
for (Iterator iter = destroyedListeners.iterator(); iter.hasNext();)
{
((FlexSessionListener)iter.next()).sessionDestroyed(this);
}
destroyedListeners.clear();
}
// Unbind all attributes.
if (attributes != null && !attributes.isEmpty())
{
Object[] keys = attributes.keySet().toArray();
for (int i = 0; i < keys.length; ++i)
removeAttribute((String)keys[i]);
attributes = null;
}
internalInvalidate();
synchronized (lock)
{
valid = false;
invalidating = false;
}
// Notify any waiting threads.
if (waitMonitor != null)
{
for (FlexClient.EndpointQueue endpointQueue : waitMonitor.values())
{
synchronized (endpointQueue)
{
endpointQueue.notifyAll();
}
}
}
}
/**
* Hook for subclasses to perform any custom shutdown.
* Invoked after the FlexSession has performed generic shutdown but right before the session's valid
* property flips to false.
*/
protected void internalInvalidate() {}
/**
* Returns a snapshot of the FlexClients associated with the FlexSession
* when this method is invoked.
* This list is not guaranteed to remain consistent with the actual list
* of active FlexClients associated with the FlexSession over time.
*
* @return A snapshot of the current list of FlexSessions associated with the FlexClient.
*/
public List<FlexClient> getFlexClients()
{
List<FlexClient> currentFlexClients = null;
synchronized (lock)
{
checkValid(); // Re-enters lock but should be fast because we're already holding it.
currentFlexClients = new ArrayList<FlexClient>(flexClients); // Make a copy of the current list to return.
}
return currentFlexClients;
}
/**
* Returns a snapshot of the MessageClients (subscriptions) associated with the FlexSession
* when this method is invoked.
* This list is not guaranteed to remain consistent with the actual list
* of active MessageClients associated with the FlexSession over time.
*
* @return A snapshot of the current list of MessageClients associated with the FlexSession.
*/
public List getMessageClients()
{
List currentMessageClients = null;
synchronized (lock)
{
checkValid(); // Re-enters lock but should be fast because we're already holding it.
currentMessageClients = (messageClients != null) ? new ArrayList(messageClients) // Make a copy of the current list to return.
: new ArrayList(); // Return an empty list.
}
return currentMessageClients;
}
/**
* Returns the Id for the session.
*
* @return The Id for the session.
*/
public abstract String getId();
/**
* Returns whether the current user is in the specified role.
*
* @param role The role to test.
* @return true if the user is in the role; otherwise false.
*/
public boolean isUserInRole(String role)
{
ArrayList list = new ArrayList();
list.add(role);
return FlexContext.getMessageBroker().getLoginManager().checkRoles(userPrincipal, list);
}
/**
* Returns whether the session is valid.
*
* @return true if the session is valid; otherwise false.
*/
public boolean isValid()
{
synchronized (lock)
{
return valid;
}
}
/**
* @exclude
* Implements FlexClientListener interface.
* Notification that a FlexClient was created.
* This is a no-op because the FlexSession is never added as a static FlexClient created listener
* but this method is required by the interface. We only listen for the destroyed event from
* associated FlexClients.
*
* @param flexClient The FlexClient that was created.
*/
public void clientCreated(FlexClient flexClient) {}
/**
* @exclude
* Implements FlexClientListener interface.
* Notification that an associated FlexClient was destroyed.
*
* @param flexClient The FlexClient that was destroyed.
*/
public void clientDestroyed(FlexClient flexClient)
{
unregisterFlexClient(flexClient);
}
/**
* @exclude
* Used internally to associate a FlexClient with the FlexSession.
*
* @param flexClient The FlexClient to assocaite with the session.
*/
public void registerFlexClient(FlexClient flexClient)
{
if (flexClients.addIfAbsent(flexClient))
{
flexClient.addClientDestroyedListener(this);
flexClient.registerFlexSession(this);
}
}
/**
* @exclude
* Used internally to disassociate a FlexClient from the FlexSession.
*
* @param flexClient The FlexClient to disassociate from the session.
*/
public void unregisterFlexClient(FlexClient flexClient)
{
if (flexClients.remove(flexClient))
{
flexClient.removeClientDestroyedListener(this);
flexClient.unregisterFlexSession(this);
}
}
/**
* @exclude
* Used internally to associate a MessagClient (subscription) with the FlexSession.
*
* @param messageClient The MessageClient to associate with the session.
*/
public void registerMessageClient(MessageClient messageClient)
{
if (messageClients == null)
{
synchronized (lock)
{
if (messageClients == null)
messageClients = new CopyOnWriteArrayList();
}
}
if (messageClients.addIfAbsent(messageClient))
messageClient.addMessageClientDestroyedListener(this);
}
/**
* @exclude
* Used internally to disassociate a MessageClient (subscription) from a FlexSession.
*
* @param messageClient The MessageClient to disassociate from the session.
*/
public void unregisterMessageClient(MessageClient messageClient)
{
if (messageClients != null)
{
if (messageClients.remove(messageClient))
messageClient.removeMessageClientDestroyedListener(this);
}
}
/**
* Default implementation invokes <code>invalidate()</code> upon timeout.
*
* @see flex.messaging.util.TimeoutCapable#timeout()
*/
public void timeout()
{
invalidate();
}
//--------------------------------------------------------------------------
//
// Protected Methods
//
//--------------------------------------------------------------------------
/**
* Ensures that the session has not been invalidated.
*/
protected void checkValid()
{
synchronized (lock)
{
if (!valid)
{
LocalizedException e = new LocalizedException();
e.setMessage(FLEX_SESSION_INVALIDATED);
throw e;
}
}
}
/**
* Notify attribute listeners that an attribute has been added.
*
* @param name The name of the attribute.
* @param value The new value of the attribute.
*/
protected void notifyAttributeAdded(String name, Object value)
{
if (attributeListeners != null && !attributeListeners.isEmpty())
{
FlexSessionBindingEvent event = new FlexSessionBindingEvent(this, name, value);
// CopyOnWriteArrayList is iteration-safe from ConcurrentModificationExceptions.
for (Iterator iter = attributeListeners.iterator(); iter.hasNext();)
((FlexSessionAttributeListener)iter.next()).attributeAdded(event);
}
}
/**
* Notify binding listener that it has been bound to the session.
*
* @param name The attribute name.
* @param value The attribute that has been bound.
*/
protected void notifyAttributeBound(String name, Object value)
{
if ((value != null) && (value instanceof FlexSessionBindingListener))
{
FlexSessionBindingEvent bindingEvent = new FlexSessionBindingEvent(this, name);
((FlexSessionBindingListener)value).valueBound(bindingEvent);
}
}
/**
* Notify attribute listeners that an attribute has been removed.
*
* @param name The name of the attribute.
* @param value The previous value of the attribute.
*/
protected void notifyAttributeRemoved(String name, Object value)
{
if (attributeListeners != null && !attributeListeners.isEmpty())
{
FlexSessionBindingEvent event = new FlexSessionBindingEvent(this, name, value);
// CopyOnWriteArrayList is iteration-safe from ConcurrentModificationExceptions.
for (Iterator iter = attributeListeners.iterator(); iter.hasNext();)
((FlexSessionAttributeListener)iter.next()).attributeRemoved(event);
}
}
/**
* Notify attribute listeners that an attribute has been replaced.
*
* @param name The name of the attribute.
* @param value The previous value of the attribute.
*/
protected void notifyAttributeReplaced(String name, Object value)
{
if (attributeListeners != null && !attributeListeners.isEmpty())
{
FlexSessionBindingEvent event = new FlexSessionBindingEvent(this, name, value);
// CopyOnWriteArrayList is iteration-safe from ConcurrentModificationExceptions.
for (Iterator iter = attributeListeners.iterator(); iter.hasNext();)
((FlexSessionAttributeListener)iter.next()).attributeReplaced(event);
}
}
/**
* Notify binding listener that it has been unbound from the session.
*
* @param name The attribute name.
* @param value The attribute that has been unbound.
*/
protected void notifyAttributeUnbound(String name, Object value)
{
if ((value != null) && (value instanceof FlexSessionBindingListener))
{
FlexSessionBindingEvent bindingEvent = new FlexSessionBindingEvent(this, name);
((FlexSessionBindingListener)value).valueUnbound(bindingEvent);
}
}
/**
* Invoked by subclass upon session creation to notify all registered
* session create listeners of the event.
* This method must be invoked in the subclass constructor.
*/
protected void notifyCreated()
{
// This guard is here only to prevent duplicate notifications if there's a coding error
// in the subclass. Not likely..
synchronized (lock)
{
if (creationNotified)
return;
creationNotified = true;
}
if (!createdListeners.isEmpty())
{
// CopyOnWriteArrayList is iteration-safe from ConcurrentModificationExceptions.
for (Iterator iter = createdListeners.iterator(); iter.hasNext();)
((FlexSessionListener)iter.next()).sessionCreated(this);
}
}
}