evt dispatch thread slaughter

Hi all,

I've just noticed an interesting event while chatting
through the SIP
Communicator. After writing a message and hitting the send
button,
nothing happened (apart from the exception at the end of the
mail). My
message remained in the editable area of the chat window,
while it
appears that my interlocutor actually received it.
Re-hitting the send
button multiple times produced the same result.

After a short investigation it appears that this was the
result of three
distinct problems. One of them concerns the history service
impl,
another one is about the UI and the third is coming from the
icq
provider but could be considered  more generic.

1.  The history problem.
	I had previously exchanged cyrillic messages with that
particular 
interlocutor (who is no other but Pavel). During our
conversation Pavel 
tried various char sets looking for the one that would allow
SIP 
Communicator to show his cyrillic writings. Some of these
charsets 
however seem to have caused problems with the history
service which is 
now unable to parse contents of the files where these
messages were 
logged. (cf stack trace at the end of the message)

2. The UI problem.
	This one is pretty obvious. The exception reached the UI
(this was luck 
though since the provider might have decided to dispatch the
send event 
in another thread) but since it was a simple
RuntimeException, it got 
through the catch clauses and the user did not get notified
of the failure.

3. The third (generic) problem.
	When I try to send a message to Pavel, the history service
would get 
the SentMessageEvent and try to log it. It would open
Pavel's log file 
and ... fail with the exception pasted at the bottom. This
exception 
would surface up to the event dispatch method that delivered
the message 
event and break its execution. Since the history service has
registered 
its listener prior to the UI, the GUI service impl won't get
the message 
sent event and will leave behave as if nothing happened.

We'd, obviously need to dig into the history issue and Yana,
guess you 
could add a generic error handler on your thread group (or I
think you 
could register one with Swing). Resolving these two however
won't be enough.

I am beginning to think that we'd need to go over all
fireXxx() methods
in the communicator and add try/catch clauses around the
statements that
call the listener methods. In a modular application such as
the SIP
Communicator, it is quite possible for plugins to introduce
bugs and
throw exceptions from their callback methods, and it should
be our
responsibility to gracefully handle them and don't let them
cause much
trouble.

I am not sure which is the best and fastest way to do this
(Simply try 
catch and log might be a bit too simple ...). If anyone
has a reference to a state-of-the-art event dispatch class
published
somewhere on the net, it'd be nice to point us to it.
Otherwise I'll
simply go through all fire statements and add
catch-all-and-log clauses 
around all calls to listeners with a default of simply
logging the 
exception.

Cheers
Emil

>      [java] 13:21:10.219 FINE:
impl.protocol.icq.ProtocolProviderServiceIcqImpl.sentOtherEv
ent() reveived
ConversationEventInfo:net.kano.joustsim.oscar.oscar.service.
icbm.TypingInfo1b80c3
>      [java] 13:21:10.221 FINE:
impl.protocol.icq.ProtocolProviderServiceIcqImpl.sentMessage
() sent message event
>      [java] java.lang.RuntimeException: Error occured
while parsing XML document.
>      [java]     at
net.java.sip.communicator.impl.history.HistoryImpl.getDocume
ntForFile(HistoryImpl.java:230)
>      [java]     at
net.java.sip.communicator.impl.history.HistoryWriterImpl.cre
ateNewDoc(HistoryWriterImpl.java:175)
>      [java]     at
net.java.sip.communicator.impl.history.HistoryWriterImpl.add
Record(HistoryWriterImpl.java:89)
>      [java]     at
net.java.sip.communicator.impl.history.HistoryWriterImpl.add
Record(HistoryWriterImpl.java:63)
>      [java]     at
net.java.sip.communicator.impl.msghistory.MessageHistoryServ
iceImpl.writeMessage(MessageHistoryServiceImpl.java:452)
>      [java]     at
net.java.sip.communicator.impl.msghistory.MessageHistoryServ
iceImpl.messageDelivered(MessageHistoryServiceImpl.java:429)
>      [java]     at
net.java.sip.communicator.impl.protocol.icq.OperationSetBasi
cInstantMessagingIcqImpl.fireMessageEvent(OperationSetBasicI
nstantMessagingIcqImpl.java:459)
>      [java]     at
net.java.sip.communicator.impl.protocol.icq.OperationSetBasi
cInstantMessagingIcqImpl.sendInstantMessage(OperationSetBasi
cInstantMessagingIcqImpl.java:232)
>      [java]     at
net.java.sip.communicator.impl.gui.main.message.ChatSendPane
l.actionPerformed(ChatSendPanel.java:100)
>      [java]     at
javax.swing.AbstractButton.fireActionPerformed(AbstractButto
n.java:1786)
>      [java]     at
javax.swing.AbstractButton$ForwardActionEvents.actionPerform
ed(AbstractButton.java:1839)
>      [java]     at
javax.swing.DefaultButtonModel.fireActionPerformed(DefaultBu
ttonModel.java:420)
>      [java]     at
javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel
.java:258)
>      [java]     at
javax.swing.AbstractButton.doClick(AbstractButton.java:289)
>      [java]     at
javax.swing.AbstractButton.doClick(AbstractButton.java:269)
>      [java]     at
net.java.sip.communicator.impl.gui.main.message.ChatPanel.se
ndMessage(ChatPanel.java:571)
>      [java]     at
net.java.sip.communicator.impl.gui.main.message.ChatWindow$S
endMessageAction.actionPerformed(ChatWindow.java:580)
>      [java]     at
javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:
1530)
>      [java]     at
javax.swing.JComponent.processKeyBinding(JComponent.java:243
8)
>      [java]     at
javax.swing.JComponent.processKeyBindings(JComponent.java:24
84)
>      [java]     at
javax.swing.JComponent.processKeyEvent(JComponent.java:2401)
>      [java]     at
java.awt.Component.processEvent(Component.java:4909)
>      [java]     at
java.awt.Container.processEvent(Container.java:1569)
>      [java]     at
java.awt.Component.dispatchEventImpl(Component.java:3615)
>      [java]     at
java.awt.Container.dispatchEventImpl(Container.java:1627)
>      [java]     at
java.awt.Component.dispatchEvent(Component.java:3477)
>      [java]     at
java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusM
anager.java:1713)
>      [java]     at
java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(Defaul
tKeyboardFocusManager.java:627)
>      [java]     at
java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(Def
aultKeyboardFocusManager.java:831)
>      [java]     at
java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(Def
aultKeyboardFocusManager.java:741)
>      [java]     at
java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKe
yboardFocusManager.java:592)
>      [java]     at
java.awt.Component.dispatchEventImpl(Component.java:3506)
>      [java]     at
java.awt.Container.dispatchEventImpl(Container.java:1627)
>      [java]     at
java.awt.Window.dispatchEventImpl(Window.java:1606)
>      [java]     at
java.awt.Component.dispatchEvent(Component.java:3477)
>      [java]     at
java.awt.EventQueue.dispatchEvent(EventQueue.java:480)
>      [java]     at
java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventD
ispatchThread.java:201)
>      [java]     at
java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDis
patchThread.java:151)
>      [java]     at
java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.
java:145)
>      [java]     at
java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.
java:137)
>      [java]     at
java.awt.EventDispatchThread.run(EventDispatchThread.java:10
0)
>      [java] Caused by: org.xml.sax.SAXParseException:
Illegal XML character 
>      [java]     at
org.apache.crimson.parser.Parser2.fatal(Parser2.java:3376)
>      [java]     at
org.apache.crimson.parser.Parser2.fatal(Parser2.java:3370)
>      [java]     at
org.apache.crimson.parser.Parser2.surrogatesToCharTmp(Parser
2.java:2677)
>      [java]     at
org.apache.crimson.parser.Parser2.maybeReferenceInContent(Pa
rser2.java:2611)
>      [java]     at
org.apache.crimson.parser.Parser2.content(Parser2.java:2017)
>      [java]     at
org.apache.crimson.parser.Parser2.maybeElement(Parser2.java:
1691)
>      [java]     at
org.apache.crimson.parser.Parser2.content(Parser2.java:1963)
>      [java]     at
org.apache.crimson.parser.Parser2.maybeElement(Parser2.java:
1691)
>      [java]     at
org.apache.crimson.parser.Parser2.content(Parser2.java:1963)
>      [java]     at
org.apache.crimson.parser.Parser2.maybeElement(Parser2.java:
1691)
>      [java]     at
org.apache.crimson.parser.Parser2.parseInternal(Parser2.java
:667)
>      [java]     at
org.apache.crimson.parser.Parser2.parse(Parser2.java:337)
>      [java]     at
org.apache.crimson.parser.XMLReaderImpl.parse(XMLReaderImpl.
java:448)
>      [java]     at
org.apache.crimson.jaxp.DocumentBuilderImpl.parse(DocumentBu
ilderImpl.java:185)
>      [java]     at
javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java
:151)
>      [java]     at
net.java.sip.communicator.impl.history.HistoryImpl.getDocume
ntForFile(HistoryImpl.java:227)
>      [java]     ... 40 more


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