/** Retrieve previous object from the remote scrollable cursor */
public Object scrollableCursorPreviousObject(
ObjID remoteScrollableCursorOid, ReadQuery query, DistributedSession session) {
Transporter transporter = null;
try {
transporter =
getRemoteSessionController()
.scrollableCursorPreviousObject(new Transporter(remoteScrollableCursorOid));
} catch (RemoteException exception) {
throw CommunicationException.errorInInvocation(exception);
}
if (transporter == null) {
return null;
}
if (!transporter.wasOperationSuccessful()) {
throw transporter.getException();
}
Object object = transporter.getObject();
if (object == null) {
// For bug 2797683 do not close if at end of stream.
return null;
}
if (query.isReadAllQuery() && (!query.isReportQuery())) { // could be DataReadQuery
object =
session.getObjectCorrespondingTo(
object,
transporter.getObjectDescriptors(),
new IdentityHashMap(),
(ObjectLevelReadQuery) query);
}
return object;
}
/** INTERNAL: Extract the correct query result from the transporter. */
public Object extractRemoteResult(Transporter transporter) {
return ((RemoteSession) getSession())
.getObjectsCorrespondingToAll(
transporter.getObject(),
transporter.getObjectDescriptors(),
new IdentityHashMap(),
this,
getContainerPolicy());
}
/** Retrieve next page size of objects from the remote cursored stream */
public Vector cursoredStreamNextPage(
RemoteCursoredStream remoteCursoredStream,
ReadQuery query,
DistributedSession session,
int pageSize) {
Transporter transporter = null;
try {
transporter =
getRemoteSessionController()
.cursoredStreamNextPage(new Transporter(remoteCursoredStream.getID()), pageSize);
} catch (RemoteException exception) {
throw CommunicationException.errorInInvocation(exception);
}
if (transporter == null) {
return null;
}
if (!transporter.wasOperationSuccessful()) {
throw transporter.getException();
}
Vector serverNextPageObjects = (Vector) transporter.getObject();
if (serverNextPageObjects == null) {
cursoredStreamClose(remoteCursoredStream.getID());
return null;
}
Vector clientNextPageObjects = serverNextPageObjects;
if (query.isReadAllQuery() && (!query.isReportQuery())) { // could be DataReadQuery
clientNextPageObjects = new Vector(serverNextPageObjects.size());
for (Enumeration objEnum = serverNextPageObjects.elements(); objEnum.hasMoreElements(); ) {
// 2612538 - the default size of Map (32) is appropriate
Object clientObject =
session.getObjectCorrespondingTo(
objEnum.nextElement(),
transporter.getObjectDescriptors(),
new IdentityHashMap(),
(ObjectLevelReadQuery) query);
clientNextPageObjects.addElement(clientObject);
}
}
return clientNextPageObjects;
}