Reserved connections are not validated by JBoss EAP

Environment

• Red Hat JBoss Enterprise Application Platform (EAP)
  • 7
  • 6
  • 5
  • 4

Issue

• Fault tolerance/connection validation¹ has been configured for an EAP datasource pool
• A connection was obtained by calling Content from docs.oracle.com is not included.DataSource.getConnection()
• A failed connection exception is raised when the connection is used
  • java.sql.SQLRecoverableException: Closed Connection
  • java.sql.SQLRecoverableException: No more data to read from socket
  • java.net.SocketException: Broken pipe
  • etc.

Resolution

• Application code must handle exceptions that arise while a connection is held (InUse) by the application component
• Upon completion of connection usage (even if the connection has failed), the application code must explicitly call Content from docs.oracle.com is not included.Connection.close() to return the connection to the pool in order to prevent a connection leak.
• The application may need to perform other cleanup activity associated with any in-progress work.
  • This may include explicit rollback if using bean managed transactions (BMT) or allowing methods to exit if using CMT since in-flight transactions cannot proceed after a connection failure.
• The application would need to retry work (if appropriate) after requesting another connection (and potentially starting a new transaction).

Root Cause

• Fault tolerance/validation configuration only impacts connections which are considered by JBoss to be Idle.
  • When a connection is obtained from the pool by calling Content from docs.oracle.com is not included.DataSource.getConnection()) that connection is considered to be InUse even if the application code is not executing a method on it
  • Only when a connection is returned to the pool by explicitly calling Content from docs.oracle.com is not included.Connection.close() is the connection considered by JBoss to be Idle
• InUse connections cannot be validated by EAP

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