On 4/30/10 2:08 AM, d...@xx wrote:
I am using last version 2.0.0 RC1
Ok.
The NPE you got was dur to the fact that the encoder is not present
anymore in the session. What MINA does is just to propagate the
exception. If you look at the stack trace, the cause in a NPE found in
line 298, which is :
296 try {
297 // Now we can try to encode the response
298 encoder.encode(session, message, encoderOut);
where the encoder has been grabbed from the session. If the session has
expired, obviously the encoder which is stored as an atttribute in this
session will be null, thus the NPE.
Basically, it won't hurt, except that getting NPE is, well, not good.
We can improve the coe by checking that the encoder is not null before
encoding the message, but as the session may expire at any moment (for
instance, a few lines later, when we try to flush the data), we will
have to deal with some other NPE.
Another possibility would be to catch the NPE and deal with this case
(an expired session while we are trying to send some data back to the
gone client). I don't really like this approach (NPE should not be
catched, IMO).
What else ? We can also keep all the attributes into the session being
closed, just to be sure that those elements won't be nul when we will
try to read them. The problem with this is that we it will put some
extra load on the server, as it will work for nothing until it detects
that the session has expired.
Not that easy :/
JY
----- Original Message ----- From: "Emmanuel Lecharny"
<elecha...@gmail.com>
To: <us...@mina.apache.org>
Sent: Friday, April 30, 2010 1:57 AM
Subject: Re: NullPointerException in ProtocolCodecFilter
Which version of MINA are you using ?
On 4/30/10 12:24 AM, Erinc Arikan wrote:
I thought it was handling that case, but in my application it was
failing to
do so. Your issue might be different than mine, but I think that,
still it's
worth looking at.
Erinc
On Thu, Apr 29, 2010 at 6:21 PM, d...@xx<d...@proxiflex.fr> wrote:
Thanks, I will try to reproduce the error with this info.
Does Mina should not handle this situation ?
JY
----- Original Message ----- From: "Erinc
Arikan"<erincari...@gmail.com>
To:<us...@mina.apache.org>
Sent: Friday, April 30, 2010 12:07 AM
Subject: Re: NullPointerException in ProtocolCodecFilter
I've seen similar errors with my application too, Generally it
happens, if
client closes the connection before you write into the session.
If I were you, I'd check if that's the case.
Erinc
On Thu, Apr 29, 2010 at 6:02 PM, d...@xx<d...@proxiflex.fr> wrote:
One of my customers has very rare exceptions like this and I
can't find
any
explanation in my code :
org.apache.mina.filter.codec.ProtocolEncoderException:
java.lang.NullPointerException
at
org.apache.mina.filter.codec.ProtocolCodecFilter.filterWrite(ProtocolCodecFilter.java:313)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain.callPreviousFilterWrite(DefaultIoFilterChain.java:506)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain.access$1400(DefaultIoFilterChain.java:46)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain$EntryImpl$1.filterWrite(DefaultIoFilterChain.java:805)
at
org.apache.mina.filter.executor.ExecutorFilter.filterWrite(ExecutorFilter.java:706)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain.callPreviousFilterWrite(DefaultIoFilterChain.java:506)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain.access$1400(DefaultIoFilterChain.java:46)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain$EntryImpl$1.filterWrite(DefaultIoFilterChain.java:805)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain$TailFilter.filterWrite(DefaultIoFilterChain.java:731)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain.callPreviousFilterWrite(DefaultIoFilterChain.java:506)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain.fireFilterWrite(DefaultIoFilterChain.java:498)
at
org.apache.mina.core.session.AbstractIoSession.write(AbstractIoSession.java:428)
at
org.apache.mina.core.session.AbstractIoSession.write(AbstractIoSession.java:369)
at
fr.proxiflex.axx.server.HTTPReceivedHandler.handleMessage(HTTPReceivedHandler.java:38)
at
org.apache.mina.handler.demux.DemuxingIoHandler.messageReceived(DemuxingIoHandler.java:232)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain$TailFilter.messageReceived(DefaultIoFilterChain.java:713)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain.callNextMessageReceived(DefaultIoFilterChain.java:434)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain.access$1200(DefaultIoFilterChain.java:46)
at
org.apache.mina.core.filterchain.DefaultIoFilterChain$EntryImpl$1.messageReceived(DefaultIoFilterChain.java:793)
at
org.apache.mina.core.filterchain.IoFilterEvent.fire(IoFilterEvent.java:71)
at org.apache.mina.core.session.IoEvent.run(IoEvent.java:63)
at
org.apache.mina.filter.executor.OrderedThreadPoolExecutor$Worker.runTask(OrderedThreadPoolExecutor.java:780)
at
org.apache.mina.filter.executor.OrderedThreadPoolExecutor$Worker.runTasks(OrderedThreadPoolExecutor.java:772)
at
org.apache.mina.filter.executor.OrderedThreadPoolExecutor$Worker.run(OrderedThreadPoolExecutor.java:714)
at java.lang.Thread.run(Thread.java:619)
Caused by: java.lang.NullPointerException
at
org.apache.mina.filter.codec.ProtocolCodecFilter.filterWrite(ProtocolCodecFilter.java:298)
... 24 more
Anybody have any idea of what it can come from ?
I can give more information if necessary, but the exception seams
to be
internal to Mina.
In case, the HTTPReceivedHandler code is :
public class HTTPReceivedHandler implements MessageHandler
{
private String root ;
public HTTPReceivedHandler( String root )
{
Log.info( "root=" + root ) ;
this.root = root ;
}
@Override
public void handleMessage( IoSession session, Object message )
throws
Exception
{
Log.trace( "R" ) ;
HTTPMessage msg = (HTTPMessage)message ;
Log.received( msg ) ;
msg.execute( root ) ;
session.write( msg ) ; //<<<< line 38
}
}
Thanks
Jean-Yves Linet
--
Regards,
Cordialement,
Emmanuel Lécharny
www.nextury.com
--
Regards,
Cordialement,
Emmanuel Lécharny
www.nextury.com
