Lucene.Net.Index.IndexWriter.StartTransaction C# (CSharp) Method

		private void  StartTransaction(bool haveReadLock)
		{
			lock (this)
			{
				
				bool success = false;
				try
				{
					if (infoStream != null)
						Message("now start transaction");
					
					System.Diagnostics.Debug.Assert(docWriter.GetNumBufferedDeleteTerms() == 0 , 
						"calling startTransaction with buffered delete terms not supported: numBufferedDeleteTerms=" + docWriter.GetNumBufferedDeleteTerms());
					System.Diagnostics.Debug.Assert(docWriter.NumDocsInRAM == 0 , 
						"calling startTransaction with buffered documents not supported: numDocsInRAM=" + docWriter.NumDocsInRAM);
					
					EnsureOpen();
					
					// If a transaction is trying to roll back (because
					// addIndexes hit an exception) then wait here until
					// that's done:
					lock (this)
					{
						while (stopMerges)
							DoWait();
					}
					success = true;
				}
				finally
				{
					// Release the write lock if our caller held it, on
					// hitting an exception
					if (!success && haveReadLock)
						ReleaseRead();
				}
				
				if (haveReadLock)
				{
					UpgradeReadToWrite();
				}
				else
				{
					AcquireWrite();
				}
				
				success = false;
				try
				{
					localRollbackSegmentInfos = (SegmentInfos) segmentInfos.Clone();
					
					System.Diagnostics.Debug.Assert(!HasExternalSegments());
					
					localFlushedDocCount = docWriter.GetFlushedDocCount();

                    // Remove the incRef we did in startTransaction:
					deleter.IncRef(segmentInfos, false);
					
					success = true;
				}
				finally
				{
					if (!success)
						FinishAddIndexes();
				}
			}
		}