Applet-Servlet Communication EOFException

[drewich]

Hi! i´ve been searching and searching through forums because it seems this problem is very common, but none of the solutions i´ve seen so far suits me, so i´m here looking for some help because i´ve been stuck one week with this. First of all sorry if my english isn´t the best... i´m a bit rusty...

Well, i had some code that worked perfectly, but i needed to perform some changes because i needed the servlet to send more info to the applet, and here started the problems, when i made the changes it started to throw EOFException when i was trying to read the InputStream, and furthermore when i came back to the original code it started to throw the exception in the same place too :banghead:

So here i am... don´t know what to do now and i entrust to you to give me some tips.

Here comes some code.

Applet:
public ListasComponentesSeleccionables cargarListasComponentes( ) throws IOException, ClassNotFoundException {

String serv = "/Desaladora/cargarListasComponentesApplet.do";
String host = Principal.documentBase.getHost( );

URL direccion = new URL( "http", host, 8080, serv );
// Create conection
URLConnection connection = direccion.openConnection( );

connection.setDoInput( true );
connection.setDoOutput( true );
connection.setUseCaches( false );

connection.setRequestProperty( "Content-Type", "application/x-java-serialized-object" );

ObjectOutputStream output;
output = new ObjectOutputStream( connection.getOutputStream( ) );

output.writeObject( new Boolean(true) );

output.flush( );
output.close( );


ObjectInputStream input = new ObjectInputStream( connection.getInputStream( ) ); //<-- Here is the problem
ListasComponentesSeleccionables response = new ListasComponentesSeleccionables( );

response = ( ListasComponentesSeleccionables ) input.readObject( );

return response;
}

Servlet:

public class CargarListasComponentesAppletAction extends Action {


public ActionForward execute( ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response ) throws ServletException, IOException, Exception {

InitialContext context = new InitialContext();
SensorManagerService sensor_service;
ActuatorManagerService actuator_service;


Globals.LOGGER_SECURITY.debug( "Entering ACTION 'CargarListasComponentesAppletAction'" );

response.setContentType("application/x-java-serialized-object");

try
{

ObjectInputStream bufferentrada = new ObjectInputStream(request.getInputStream());

Boolean peticionOK = (Boolean)bufferentrada.readObject();


ObjectOutputStream buffersalida = new ObjectOutputStream(response.getOutputStream());


sensor_service = ( SensorManagerService ) context.lookup( "desaladora/SensorManagerServiceBean/local" );
ArrayList<AlarmConnectedSensorDTO> sensorList = sensor_service.findAllSensorsToAlarms();

actuator_service = ( ActuatorManagerService ) context.lookup( "desaladora/ActuatorManagerServiceBean/local" );
ArrayList<AlarmConnectedActuatorDTO> actuatorList = actuator_service.findAllActuatorsToAlarms();


buffersalida.writeObject( crearListasSeleccionables(sensorList, actuatorList) );


buffersalida.flush();
}
catch(Exception e)
{
System.out.println("Error en la trasmision de datos");
}

return null;
}

private ListasComponentesSeleccionables crearListasSeleccionables(ArrayList<AlarmConnectedSensorDTO> sensorList, ArrayList<AlarmConnectedActuatorDTO> actuatorList) {

Vector<Integer> vectorSensores = new Vector<Integer>();
Vector<Integer> vectorActuadores = new Vector<Integer>();

for(AlarmConnectedSensorDTO sensor : sensorList) {
vectorSensores.add(sensor.getIdSensor( ));
}
for(AlarmConnectedActuatorDTO actuator : actuatorList) {
vectorActuadores.add(actuator.getIdActuator( ));
}
ListasComponentesSeleccionables listasComponentesSeleccionables = new ListasComponentesSeleccionables(vectorSensores, vectorActuadores);

return listasComponentesSeleccionables;
}

}



Thank you for your time

[drewich]

i´ve been running some test in another computer, and that code simply works, but it doesn´t work in the machine i usually work.

Maybe someway the stream get corrupt? the info i´ve been trying to send and started throwing the exception may still be in the stream? I don´t know what to think right now