When failover happens on aurora db cluster, no new connection can be initiated to the db, each attempt generating NPE.

This is the failover triggered exception:
java.sql.SQLException: (conn=322421) Communications link failure with secondary host xxxxx.amazonaws.com:3306. Connection timed out. Driver has reconnect connection
at org.mariadb.jdbc.internal.util.exceptions.ExceptionMapper.get(ExceptionMapper.java:264)
at org.mariadb.jdbc.internal.util.exceptions.ExceptionMapper.getException(ExceptionMapper.java:171)
at org.mariadb.jdbc.MariaDbStatement.executeExceptionEpilogue(MariaDbStatement.java:248)
at org.mariadb.jdbc.ServerSidePreparedStatement.executeInternal(ServerSidePreparedStatement.java:432)
at org.mariadb.jdbc.ServerSidePreparedStatement.execute(ServerSidePreparedStatement.java:386)
at org.mariadb.jdbc.ServerSidePreparedStatement.executeQuery(ServerSidePreparedStatement.java:365)
....
Caused by: java.sql.SQLException: Communications link failure with secondary host xxxxx.amazonaws.com:3306. Connection timed out. Driver has reconnect connection
at org.mariadb.jdbc.internal.failover.AbstractMastersListener.throwFailoverMessage(AbstractMastersListener.java:545)
at org.mariadb.jdbc.internal.failover.FailoverProxy.handleFailOver(FailoverProxy.java:367)
at org.mariadb.jdbc.internal.failover.FailoverProxy.invoke(FailoverProxy.java:238)
at com.sun.proxy.$Proxy13.executePreparedQuery(Unknown Source)
at org.mariadb.jdbc.ServerSidePreparedStatement.executeInternal(ServerSidePreparedStatement.java:425)
... 26 more
Caused by: java.sql.SQLNonTransientConnectionException: Read timed out
at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.handleIoException(AbstractQueryProtocol.java:1925)
at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.readPacket(AbstractQueryProtocol.java:1437)
at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.getResult(AbstractQueryProtocol.java:1415)
at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.executePreparedQuery(AbstractQueryProtocol.java:1050)
at sun.reflect.GeneratedMethodAccessor31.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.mariadb.jdbc.internal.failover.AbstractMastersListener.invoke(AbstractMastersListener.java:401)
at org.mariadb.jdbc.internal.failover.FailoverProxy.invoke(FailoverProxy.java:233)
... 28 more
Caused by: java.net.SocketTimeoutException: Read timed out
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
at java.net.SocketInputStream.read(SocketInputStream.java:171)
at java.net.SocketInputStream.read(SocketInputStream.java:141)
at java.io.FilterInputStream.read(FilterInputStream.java:133)
at org.mariadb.jdbc.internal.io.input.ReadAheadBufferedStream.fillBuffer(ReadAheadBufferedStream.java:130)
at org.mariadb.jdbc.internal.io.input.ReadAheadBufferedStream.read(ReadAheadBufferedStream.java:103)
at org.mariadb.jdbc.internal.io.input.StandardPacketInputStream.getPacketArray(StandardPacketInputStream.java:244)
at org.mariadb.jdbc.internal.io.input.StandardPacketInputStream.getPacket(StandardPacketInputStream.java:215)
at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.readPacket(AbstractQueryProtocol.java:1435)

And then, on any attempt to reconnect:
java.lang.NullPointerException
at org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.setHostAddress(AbstractConnectProtocol.java:1168)
at org.mariadb.jdbc.internal.protocol.AuroraProtocol.loop(AuroraProtocol.java:166)
at org.mariadb.jdbc.internal.failover.impl.AuroraListener.reconnectFailedConnection(AuroraListener.java:210)
at org.mariadb.jdbc.internal.failover.impl.MastersSlavesListener.initializeConnection(MastersSlavesListener.java:170)
at org.mariadb.jdbc.internal.failover.FailoverProxy.<init>(FailoverProxy.java:116)
at org.mariadb.jdbc.internal.util.Utils.retrieveProxy(Utils.java:543)
at org.mariadb.jdbc.MariaDbConnection.newConnection(MariaDbConnection.java:175)
at org.mariadb.jdbc.MariaDbDataSource.getConnection(MariaDbDataSource.java:288)
at org.mariadb.jdbc.MariaDbDataSource.getPooledConnection(MariaDbDataSource.java:451)

This is happening on 90% of failover cases and it requires application restart as the driver does not recover from this state.

Thanks,
Ionut