/// <summary>
/// Execute task.
/// </summary>
/// <typeparam name="T">Task return type.</typeparam>
/// <param name="context">The context of this task.</param>
/// <returns>
/// Task result.
/// </returns>
public virtual T Execute <T>(ExecutionContext <T> context)
{
int i = 0;
while (true)
{
Session session = null;
TransactionScope tran = null;
bool needBreak = false;
Transaction transaction = null;
try
{
T result;
SessionScope sessionScope = null;
try
{
try
{
IsolationLevel isolationLevel = context.IsolationLevel;
SystemTransaction currentTransaction = SystemTransaction.Current;
if (isolationLevel == IsolationLevel.Unspecified && currentTransaction != null)
{
isolationLevel = currentTransaction.IsolationLevel;
}
session = SessionScope.CurrentSession;
if (session == null)
{
session = context.Domain.OpenSession();
sessionScope = session.Activate();
}
if (currentTransaction != null && session.Transaction != null)
{
session.EnsureTransactionIsStarted();
}
tran = (currentTransaction != null && currentTransaction.TransactionInformation.DistributedIdentifier != Guid.Empty) ||
(session.Transaction != null && session.Transaction.IsDisconnected)
? session.OpenTransaction(isolationLevel)
: session.OpenTransaction(context.TransactionOpenMode, isolationLevel);
transaction = session.Transaction;
result = context.Function(session);
tran.Complete();
}
finally
{
try
{
tran.DisposeSafely();
}
catch (StorageException e)
{
if (e.InnerException == null || !(e.InnerException is InvalidOperationException) ||
e.InnerException.Source != "System.Data")
{
throw;
}
if (tran.Transaction.IsNested)
{
needBreak = true;
}
}
}
}
finally
{
sessionScope.DisposeSafely();
if (SessionScope.CurrentSession != session)
{
session.DisposeSafely();
}
}
return(result);
}
catch (Exception e)
{
if ((SystemTransaction.Current != null &&
SystemTransaction.Current.TransactionInformation.DistributedIdentifier != Guid.Empty) ||
(transaction != null && (transaction.State == TransactionState.Active || transaction.IsDisconnected)))
{
throw;
}
if (e is RollbackTransactionException)
{
return(default(T));
}
i++;
if (needBreak || !HandleException(new ExecuteErrorEventArgs(e, session, transaction, i)))
{
throw;
}
}
}
}
