Component: driver-core (com.mongodb.internal.connection)
Related: JAVA-6057

Description

With timeoutMS set, socket timeouts should surface as MongoOperationTimeoutException. This translation happens on the read path but not the write path: InternalStreamConnection.throwTranslatedWriteException(...) only converts MongoSocketWriteTimeoutException, so a bare java.net.SocketTimeoutException on write falls through to MongoSocketWriteException. translateReadException(...) already translates a bare SocketTimeoutException — the two paths are inconsistent.

Reproduces on Windows + TLS (shouldUseConnectTimeoutMsWhenEstablishingConnectionInBackground, all topologies):

expected  but was 
Caused by: java.net.SocketTimeoutException: Read timed out

On Windows an SSLSocket write blocks reading TLS records, so the read-timeout fires during the send and reaches the write path.

Fix

In throwTranslatedWriteException, when hasTimeoutMS(), translate a bare SocketTimeoutException to MongoOperationTimeoutException (mirroring the read path); add a test.

Why this is not a backwards-breaking change

• No API change — no signatures, public types, or method contracts change; fully binary-compatible.
• Behaviour change is confined to the timeoutMS (CSOT) path, and only when a socket timeout occurs during a write. It swaps one MongoException subtype for another (MongoSocketWriteException -> MongoOperationTimeoutException).
• The new exception is the correct/documented one — the operation genuinely timed out under timeoutMS, and the CSOT contract specifies MongoOperationTimeoutException for that case. The old behaviour was an inconsistency, not a contract.
• It makes write consistent with read, which already returns MongoOperationTimeoutException for the same underlying SocketTimeoutException.