Appia communication framework Files

==========================
04/01/2011   Version 4.1.2
==========================

(SVN revision 440)

- Bug fix on the TcpComplete protocol (RegisterSocketEvent) on the case that no IP address was given 
  and several network interfaces are present in the machine;
- Added a sequencer based total order protocol that is based on SETO, but without the estimated optimistic deliveries. 
  The new protocol (SequencerUniform) provides Uniform Total Order with optimistic deliveries.
- Small fixes and code improvements.


==========================
15/09/2010   Version 4.1.1
==========================

(SVN revision 433)

Removed NPE in ViewState.java;
Added parameterized code in several classes;
Fixed several bugs in the JMX management interfaces of Appia and added a wrapper for client applications to connect and manage an Appia process;
Added management interfaces to the RemoteAddress protocol;
Fixed some bugs in the JMX interfaces;
Improved the code of the JMX interfaces and added the possibility to retrieve a local instance of the Channel dynamic managed bean;
Improved the "open group" tests;
Fixed minor issues in the TCPComplete protocol;
Added the symmetric total order protocol;
Added the hybrid total order protocol implemented by Pedro Vicente;
Added a configuration for the uniformity info periodic timer;
Solved an ArrayIndexOutOfBounds exception that hapened when Appia was configured to use several channels, the views were multiplexed and one of the channels is holding the view;
Added JMX management to the token based total order protocol;
Removed (commented) the code that delays the rotation of the token;
Bugfix on the register socket event when the user wanted to bind to a specific address.

==========================
16/01/2009   Version 4.1.0
==========================

(SVN revision 387)

Refactored all the code to separate the Appia core and the group communication protocols.
With this change, now the Appia core can be used without having to carry lots of uneeded
protocols if (for instance) you are building p2p protocols;
Fixed some small issues in the jGCS implementation;
Changed several protocols to use generics in their data structures;
Added a new failure detector protocol (PhiSuspect) based on the work of Naohiro Hayashibara. This
protocol was implemented by Dan Mihai Dumitriu. Thanks for the contribution!

==========================
06/12/2007   Version 4.0.1
==========================

(SVN revision 333)

Fixed a small issue on the Appia kernel;
Added examples that show how to use jGCS with Appia;
Added some examples that show how to use open groups with Appia and jGCS;
Fixed small issues in the RemoteView protocol.

==========================
29/10/2007   Version 4.0.0
==========================

(SVN revision 311)

Replaced package names.
Added JMX interfaces to retrieve information about Membership and Throughput;
JMX interfaces are now created dynamically;
Several bug fixes in the failure detector protocol;
Introduced a sender thread in the TCP protocol to avoid blocking the Appia main thread;
Fixed several issues on the Primary View protocol;
Added the implementation of jGCS version 0.6.1. Appia is now fully jGCS compliant;
Started using the Java 5 features, including the JMX implementation;
Dropped mx4j libraries;

========================
25/06/2007   Version 3.3
========================

Release Notes:

** Bug
    * [APPIA-54] - Frag protocol should not create Messages explicitly
    * [APPIA-69] - Improve failure detection in cases of high load of messages.
    * [APPIA-76] - Several protocols must have a special case for the LeaveEvent.
    * [APPIA-77] - Views are not properly handled by non primary elements by the primary protocol.
    * [APPIA-79] - Error on parsing parameters in the GossipServer main class.
    * [APPIA-80] - Creating a channel using a non-existant XML template results in a NullPointerException

** New Feature
    * [APPIA-32] - Add the Total Order switching protocol to the CVS head
    * [APPIA-75] - Add JMX interfaces to the primary view protocol.

** Task
    * [APPIA-25] - Remove hand conversions from integer to byte[] and vice-versa on several protocols.
    * [APPIA-51] - Update Javadoc on remote view protocol
    * [APPIA-58] - Remove deprecated class org.continuent.appia.protocols.sslcomplete.SslCompleteConfig.
    * [APPIA-63] - Remove deprecated class InetWithPort
    * [APPIA-73] - Fix javadoc issues
    * [APPIA-74] - Move the int to byte array conversions to an independent Util class.

** Improvement
    * [APPIA-23] - Reduce CPU consumption on TotalToken when not sending any messages.
    * [APPIA-33] - Implement management interfaces in the TO switching protocol to change the TO protocol using JMX management. 
    * [APPIA-49] - Change the retrievement method of the Appia ThreadFactory instance
    * [APPIA-65] - Create an abstract Message factory
    * [APPIA-66] - Thread and messages factories should be defined in the XML config file.
    * [APPIA-67] - Make sleep time configurable in the token total order protocol.
    * [APPIA-70] - Change the debug messages of the group communication protocols to use Log4j
    * [APPIA-71] - Change the debug messages of several protocols to use Log4j
    * [APPIA-72] - Filter block events on the primary view protocol when blocked on non-primary view.
    * [APPIA-78] - Rewrite the uniform protocol.

========================
16/01/2007 Version 3.2.4
========================

Release Notes:

** Bug
    * [APPIA-55] - In NakFifoMulticast, the last channel used must be saved.
    * [APPIA-61] - LoopBack protocol should not clone messages that are not to all members of the group.

** New Feature
    * [APPIA-1] - Initial configuration of a group membership

** Task
    * [APPIA-36] - Complete javadoc on XML classes
    * [APPIA-59] - Document better the register socket event class
    * [APPIA-60] - Add a getSocketAddress method in thr RegisterSocketEvent class.
    * [APPIA-62] - Fix javadoc issues introduced recently
    * [APPIA-64] - Create a XML example for the SSL protocol in the config/demo directory.

** Improvement
    * [APPIA-52] - Scheduled events when closing channel.
    * [APPIA-56] - Replace InetSocketAddress by SocketAddress where is possible.
    * [APPIA-57] - Allow XML configuration on the SslComplete protocol for the possible parameters


========================
15/09/2006 Version 3.2.3
========================

Release Notes:

** Bug
    * [APPIA-29] - NullPointerException on FifoSession

** New Feature
    * [APPIA-48] - Create Remote View Protocol

** Task
    * [APPIA-26] - Create hierarchy between Undelivered events.
    * [APPIA-40] - Remove deprecated class ExtendedMessage

** Improvement
    * [APPIA-50] - Improve the Ecco example in order to be compliant with the new Appia features.


========================
15/09/2006 Version 3.2.2
========================

This release contains some bug fixes in the Message class and in the protocol that makes the interface
between the Appia protocols and UDP sockets, when using multicast.

Release Notes:

** Bug
    * [APPIA-44] - pop, push or peek methods of the Message class may lead to message corruption.
    * [APPIA-45] - In some systems, binding the multicast socket of UdpSimple to the multicast address raises an exception

** Task
    * [APPIA-31] - Remove deprecated class org.continuent.appia.protocols.fifo.MulticastHeader

** Improvement
    * [APPIA-46] - Add info about a failure of a RegisterSocket Event in the event (Exception and Error code).

========================
06/09/2006 Version 3.2.1
========================

This release contains some important bug fixes in the message class and 
an optimization in the same class when deserializing objects. It contains also a bug fix in 
the DTD specification.

Release notes: 

** Bug
    * [APPIA-39] - memorymanagement tag is not correctly configured in DTD file
    * [APPIA-41] - Stream corrupted exception when using Appia with Sequoia under high load

** New Feature
    * [APPIA-43] - Create protocol to check the integrity of a message in any point of the channel stack, based in the message size.

======================
28/08/2006 Version 3.2
======================

This new version contains fixes for several issues on protocols, a new management interface for protocols to
be accessed by JMX, and several improvements that include Thread management, Javadoc descriptions and exception
handling. The issues solved for this release are listed as follows:

** Bug
    * [APPIA-18] - Remove System.currentTimeMillis() direct calls
    * [APPIA-19] - Handling of IOException in the UdpSimpleSession (when sending to the socket) not being taken care properly.
    * [APPIA-29] - NullPointerException on FifoSession

** New Feature
    * [APPIA-6] - Create JMX interfaces to manage Appia channels and parameters.
    * [APPIA-12] - Add Trowable cause to Appia exceptions.

** Task
    * [APPIA-3] - Replace InetWithPort by InetSocketAddress

** Improvement
    * [APPIA-15] - Replace all Serializable Appia objects to the Externalizable interface.
    * [APPIA-17] - Improve Exception handling in the XML configuration.
    * [APPIA-20] - Create a Thread factory and create Threads from this factory. This threads are usually needed to receive messages from sockets.
    * [APPIA-24] - Create a default runnable implementation for the Appia thread to ease the Appia interface with programmers.


========================
21/06/2006 Version 3.1.1
========================

- Several bug fixes in the SETO total order protocol and in the NakFifoMulticast protocol.

======================
27/04/2006 Version 3.1
======================

- Added push, pop and peek for InetSocketAddress in the Message class This is hidden in the push/pop/peekObject methods.
- Added generic events to be used by total order protocols that need to provide information about message guarantees. 
  These events are used to provide optimistic assumptions and guarantees about message delivery.
- Added an optimistic sequencer based total order protocol that provides optimistic assumptions about message delivery.
  Upon reception of a message, it forwards that message to the application and after that sends notifications about message
  guaranties: SETO (estimated total order), when the message is considered optimistically ordered; Regular, 
  when the message is ordered by the sequencer; Uniform, when the message is considered uniform.  
- Refactored the total order protocols.
- Removed several minor bug fixes.
- Updated javadoc information.

======================
20/03/2006 Version 3.0
======================

- Changed Appia license from LGPL to Apache License version 2.0.
- Refactored all the code to be hosted on Continuent.org GForge site.
- Fixed several small issues.
- Updated javadoc documentation.

======================
09/12/2005 Version 2.1
======================

- Protocols: Added new Total Order protocol, implemented using a token. 
- Memory management: Added the funtionality of defining channels with memory management in XML.
- Memory management: Added different thresholds for UP and DOWN events. Each directions has a different value for the threshold.
- Event scheduling: Inserted the notion of priority on events. Timers have more priority then normal events.
- Message: The classes ObjectsMessage, ExtendedMessage and Message were merged and there is only one message now.
- Message: Added discardAll() method for performance tunning.
- Bug fixes in the following functionalities:
	- Some resources were not beeing garbage colected;
	- Fragmentation of cloned messages.
	- The localhost must be set using information of RegisterSocketEvent and this was not being done in several protocols.
- Updated javadoc documentation.
- Added serialVersionUIDs to Serializable objects.
- Added XML support in several protocols.
- Removed old deprecated code.

======================
20/09/2005 Version 2.0
======================

- Integrated XML capabilities.
- New Negative-Acknoledgment FIFO (NakFifo) protocol.
- Improved performance at protocol and kernel levels.
- Definetly changed RegisterSocketEvent and InetWithPort classes from appia.protocols.udpsimple to appia.protocols.common packages.
- RegisterSocketEvent now contains the local host address.
- MulticastInitEvent replaced AppiaMulticastInitEvent.
- Kernel support for several Appia instances running within the same process.
- New and improved view merge protocol that supports the merge of several views in a single change.
- Added distributed capability to GossiServer. Removed DistGossipServer.
- Several Bugfixes.

=======================
9/10/2003 Version 1.9-2
=======================

- Deprecated the use of Direction and EventQualifier. Replaced by int. Classes remain to offer static values.
- Optimized Message. Two new methods "popReadOnly" and "peekReadOnly" with improved performance.
- Created ExtendedMessage with functionality previously in ObjectsMessage. ObjectsMessage remains for compatibility.
- Rearrangement of certain classes location, namely InetWithPort and RegisterSocketEvent, to new package appia.protocols.common
- New, more reliable, TCP layer.
- New, more reliable, SSL layer.
- Extended Appl demo application, to support SSL. Removed previous applications.
- Several bug fixes.

==========
8/10/2002
==========
-Bug fixes and performance enhancements in group communication
-New protocols
-gossip and demo aplications are now in packages

==========
05/03/2002
==========
-Udp multcast support (udpsimple)
-Uniform primitives to group communication (stable uniform)
-Major re-write of the fifo protocol,better performance (fifo)
-Ssl communication layers (sslsimple for point-to-point communication and sslcomplete for group communication), needs jdk1.4
-Group Rpc system, supporting active and passive replication and limeted crash-recovery.
-various bug fixes and performance enhancements in other protocols


==========
05/07/2001
==========

This latest release offers a revised virtual-synchrony enforcing protocol. 
This new version removes:
    - the "stable.Retransmit" and "sync.Sync" layers. 
    - the "stable.Stable" and "stable.Stabilize" events.
And adds:
    - the "sync.VSync" layer.
    - the "sync.Sync" event.
    - the "stable.StableStorage" auxiliary class.

Another important change is the deprecation of the "AsyncEvent" and the "Channel.makeAsync()" and "Channel.async(...)" methods. The new mechanisms to insert asynchronous events is to use the "Event.asyncGo(...)" method.

Finally the "Appl" and "ApplMult" demo application changed to the directory "demo", and the "GossipServer" and "DistGossipServer" gossip applications changed to the "gossip" directory.