Hi, I have a problem with one of my mina based applications.
Source code where the problem manifests itself:
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.mina.core.buffer.IoBuffer;
import org.apache.mina.core.session.IoSession;
import org.apache.mina.filter.codec.CumulativeProtocolDecoder;
import org.apache.mina.filter.codec.ProtocolDecoderOutput;
import org.jpos.iso.ISOMsg;
import org.jpos.iso.ISOPackager;
public class TandemProtocolDecoder extends CumulativeProtocolDecoder {
private static final int MAX_MESSAGE_SIZE = 4196;
private Log logger = LogFactory.getLog(TandemProtocolDecoder.class);
private ISOPackager isoPackager;
public TandemProtocolDecoder(ISOPackager isoPackager) {
super();
this.isoPackager = isoPackager;
}
public ISOPackager getIsoPackager() {
return isoPackager;
}
public void setIsoPackager(ISOPackager isoPackager) {
this.isoPackager = isoPackager;
}
public TandemProtocolDecoder() {
super();
}
@Override
protected boolean doDecode(IoSession session, IoBuffer in,
ProtocolDecoderOutput out) throws Exception {
String s = new String( in.array() );
logger.debug("Choclo:" + s );
if (in.prefixedDataAvailable(2, MAX_MESSAGE_SIZE)) {
int length = in.getUnsignedShort();
byte[] bytes = new byte[length];
in.get(bytes);
ISOMsg isoMsg = new ISOMsg();
isoMsg.setPackager( isoPackager );
//TODO Si no puede realizar el unpack lanza
ISOException y entra
por exceptionCaught del conector
//Ver somo manejarlo
isoMsg.unpack( bytes );
out.write(isoMsg);
return true;
}
else{
return false;
}
}
}
Problem description:
1.- The application message (tcp payload) consist in two bytes
indicating the size of the data and the data itself.
2.- I have a test application that sends five messages to the mina application:
* Message 1 (700 bytes - well formed)
* Message 2 (100 bytes - purposely malformed ISO message)
* Message 3 (700 bytes - well formed)
* Message 4 (700 bytes - well formed)
* Message 5 (700 bytes - well formed)
3.- An IoBuffer (size = 2048) is fullfilled with msg1, msg2, msg3 and
a chunk of msg4
4.- msg1 and msg2 are processed correctly (unpacked to a isomsg and
writed to the output)
5.- The unpacking of msg3 throws and exception ( isoMsg.unpack( bytes
) ) as expected. This exception is handled by the exceptionCaught in
the IoHandler
6.- In the next call of the doDecode method the IoBuffer is filled
with rest of msg4 and msg5 (the beginning of the msg4 is lost). This
cause that 2 bytes of the msg4's data are considered
as the data size of the next message (in this case the data size,
wrongly deducted, is >>> MAX_MESSAGE_SIZE and the
prefixedDataAvailable method throws an BufferDataException exception)
Can someone tell me if there is an error in my code, is this the
expected behaviour (some workaround?) or if it is a bug?
Thank you very much in advance
Sorry for my bad English
Best regards
