Connection.supportsTransactions (still or again?) broken for Azure Synapse "serverless"

[ravenAtSafe]

Driver version

12.4.1

SQL Server version

Microsoft SQL Azure (RTM) - 12.0.2000.8
Aug 29 2023 01:39:41
Copyright (C) 2022 Microsoft Corporation

Client Operating System

Linux, Windows

JAVA/JVM version

Java 17

Table schema

n/a

Problem description

Problem 1
The first time you call supportsTransaction() against Azure Synapse "serverless" an exception with the text '@@TRANCOUNT' is not supported. is leaked out. While the driver is clearly trying to eat that exact exception it appears there is a leading space in the actual exception text that is messing everything up.

Problem 2
The second time you call supportsTransaction() it simply returns true because the first exception exercised a caching bug - when the exception is rethrown the supportsTransactions bool should be set back to null instead of being left as true.

Error message/stack trace

com.microsoft.sqlserver.jdbc.SQLServerException:  '@@TRANCOUNT' is not supported.
	at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDatabaseError(SQLServerException.java:259)
	at com.microsoft.sqlserver.jdbc.TDSTokenHandler.onEOF(tdsparser.java:304)
	at com.microsoft.sqlserver.jdbc.TDSParser.parse(tdsparser.java:137)
	at com.microsoft.sqlserver.jdbc.TDSParser.parse(tdsparser.java:42)
	at com.microsoft.sqlserver.jdbc.TDSParser.parse(tdsparser.java:31)
	at com.microsoft.sqlserver.jdbc.SQLServerConnection$1ConnectionCommand.doExecute(SQLServerConnection.java:4260)
	at com.microsoft.sqlserver.jdbc.TDSCommand.execute(IOBuffer.java:7675)
	at com.microsoft.sqlserver.jdbc.SQLServerConnection.executeCommand(SQLServerConnection.java:4137)
	at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectionCommand(SQLServerConnection.java:4268)
	at com.microsoft.sqlserver.jdbc.SQLServerConnection.supportsTransactions(SQLServerConnection.java:8105)
	at com.microsoft.sqlserver.jdbc.SQLServerDatabaseMetaData.supportsTransactions(SQLServerDatabaseMetaData.java:2190)
	at COM.safe.fme.jdbc.JdbcCommon.commitIfSupported(JdbcCommon.java:807)
	at COM.safe.fme.jdbc.JdbcReader.close(JdbcReader.java:434)
com.microsoft.sqlserver.jdbc.SQLServerException:  '@@TRANCOUNT' is not supported.

Other

This is a followup to #2071 and https://github.com/microsoft/mssql-jdbc/pull/2075/files

[Jeffery-Wasty]

We'll take another look at this.