Throw exception for "Account Locked" SQL Exception 18486

[cheenamalhotra]

This PR fixes customer issue #483 by throwing exception if Account locked Exception 18486 found.

[codecov-io]

Codecov Report

Merging #522 into dev will decrease coverage by 0.19%.
The diff coverage is 0%.

@@             Coverage Diff             @@
##                dev     #522     +/-   ##
===========================================
- Coverage     46.68%   46.48%   -0.2%     
+ Complexity     2223     2209     -14     
===========================================
  Files           108      108             
  Lines         25312    25313      +1     
  Branches       4181     4182      +1     
===========================================
- Hits          11816    11767     -49     
- Misses        11470    11521     +51     
+ Partials       2026     2025      -1

Flag	Coverage Δ	Complexity Δ
#JDBC41	46.24% <0%> (-0.13%)	2201 <0> (-9)
#JDBC42	46.36% <0%> (-0.23%)	2206 <0> (-14)

Impacted Files	Coverage Δ	Complexity Δ
...m/microsoft/sqlserver/jdbc/SQLServerException.java	76.85% <ø> (ø)	29 <0> (ø)	⬇️
.../microsoft/sqlserver/jdbc/SQLServerConnection.java	46% <0%> (-0.02%)	277 <0> (ø)
...om/microsoft/sqlserver/jdbc/SimpleInputStream.java	51.11% <0%> (-1.49%)	11% <0%> (-1%)
...rc/main/java/com/microsoft/sqlserver/jdbc/DDC.java	44.36% <0%> (-1.13%)	104% <0%> (-1%)
...om/microsoft/sqlserver/jdbc/ReaderInputStream.java	44.94% <0%> (-1.13%)	16% <0%> (-1%)
...m/microsoft/sqlserver/jdbc/SQLServerResultSet.java	32.37% <0%> (-0.78%)	238% <0%> (-7%)
...in/java/com/microsoft/sqlserver/jdbc/IOBuffer.java	54.01% <0%> (-0.57%)	0% <0%> (ø)
...c/main/java/com/microsoft/sqlserver/jdbc/Util.java	59.17% <0%> (-0.44%)	88% <0%> (-1%)
...om/microsoft/sqlserver/jdbc/SQLServerBulkCopy.java	52.58% <0%> (-0.2%)	238% <0%> (-2%)
...n/java/com/microsoft/sqlserver/jdbc/DataTypes.java	77.62% <0%> (-0.17%)	4% <0%> (-1%)
... and 3 more

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[sandeepchinnari]

@cheenamalhotra Thanks for the fix. But this will come in handy when its already too late.
What happens when the password change is in progress and concurrent threads attempt to make connections?

[cheenamalhotra]

@sandeepchinnari It would be interesting to see how one can reproduce this usecase.

As far as I understand, while request is made to Server to change password, old password is still valid. And password change is an atomic operation to update sys.sql_logins table of database with new password. After which, any new attempt will fail with an error code of 18456 (Logon Failed).

I don't see a reason, why there would be a recurrence of attempts because we are talking nanoseconds here. Even if there is a race condition, as soon as new password is updated, the attempt to connect will fail.

[cheenamalhotra]

Hi @sandeepchinnari ! Would appreciate your confirmation, if this PR fixes your failed use-case. We would like to merge the PR soon.