public override bool IsEmpty() /* throws Net.Vpc.Upa.Exceptions.UPAException */
{
if (!context.GetPersistenceUnit().GetPersistenceGroup().CurrentSessionExists())
{
if (sessionAwareInstance == null)
{
sessionAwareInstance = context.GetPersistenceUnit().GetPersistenceGroup().GetContext().MakeSessionAware <Net.Vpc.Upa.Impl.Persistence.DefaultQuery>(this);
}
return(sessionAwareInstance.IsEmpty());
}
try {
Net.Vpc.Upa.Impl.Persistence.QueryExecutor queryExecutor = ExecuteQuery(Net.Vpc.Upa.Impl.Util.Filters.Fields2.READ);
Net.Vpc.Upa.Persistence.QueryResult r = null;
try {
r = queryExecutor.GetQueryResult();
return(!r.HasNext());
} finally {
if (r != null)
{
r.Close();
}
}
} catch (System.Exception e) {
throw new Net.Vpc.Upa.Exceptions.FindException(e, new Net.Vpc.Upa.Types.I18NString("FindFailed"));
}
}
protected internal virtual Net.Vpc.Upa.Impl.Persistence.QueryExecutor ExecuteQuery(Net.Vpc.Upa.Filters.FieldFilter fieldFilter)
{
// if (result != null) {
// throw new FindException("QueryAlreadyExecutedException");
// }
Net.Vpc.Upa.Impl.Persistence.QueryExecutor queryExecutor = CreateNativeSQL(fieldFilter);
// DefaultResultMetaData m = new DefaultResultMetaData();
// for (NativeField x : queryExecutor.getFields()) {
// m.addField(x.getName(), x.getTypeTransform(), x.getField());
// }
// this.metadata = m;
queryExecutor.Execute();
result = queryExecutor.GetQueryResult();
return(queryExecutor);
}
protected internal override void LoadingFinished()
{
queryExecutor.GetQueryResult().Close();
queryExecutor.GetConnection().RemoveCloseListener(closeListener);
}
protected internal QueryResultLazyList(Net.Vpc.Upa.Impl.Persistence.QueryExecutor _queryExecutor) : base(null)
{
this.queryExecutor = _queryExecutor;
this.@base = new Net.Vpc.Upa.Impl.Persistence.QueryResultReader <R>(queryExecutor.GetQueryResult(), this);
closeListener = new Net.Vpc.Upa.Impl.Persistence.CloseListenerImpl <?>(this);
queryExecutor.GetConnection().AddCloseListener(closeListener);
}