… corresponds to an EventData returned last by the receiver (#408)

…tionReceiver and update the settings of Default & Max Prefetch count (#410)

This pull request includes two major changes related to Prefetch API.

1) Move setPrefetchCount API to the ReceiverOptions class so that prefetch value specified by a user can be used instead of using default value when communicating to the service during link open and initializing a receiver. This change also addresses the receiver stuck issue caused by setPrefetchAPI in a race condition.

2) Change the default value and set the upper bound of the prefetch count. Note that prefetch count should be greater than or equal to maxEventCount which can be set when either a) calling receive() API or b) implementing the getMaxEventCount API of the SessionReceiverHandler interface.

This pull request contains the following changes.

1) Finish pending tasks when recreating the reactor and make sure pending calls scheduled on the old reactor get complete.
2) Fix the session open timeout issue which can result in NPE in proton-J engine.
3) Make session open timeout configurable and use the value of OperationTimeout.
4) Update the message of exceptions and include an entity name in the exception message.
5) API change - use ScheduledExecutorService.
6) Improve tracing.

* ensure links are recreated on transport/connection failure
* update API document for EventProcessorOptions class
* add traces for link create/close case

…420)

* Handle proton:io errors with meaningful error msg

* Use Proton-supplied message if present

* Add logging if the scanner threw an exception.
* Change logging level to warn when scanner shuts down for any reason.
* Scanner can call EventProcessorOptions.notifyOfException, which calls user code. Change notifyOfException to defensively catch any exceptions coming out of user code.

Porting testability changes from .NET Core to Java: provide full access to EventData's SystemProperties so that a complete EventData can be fabricated in tests.

Related to Azure/qpid-proton-j-extensions#10

This fix is for issue #432. There are two parts:

AzureStorageCheckpointLeaseManager performs certain Storage actions within a forEach. If those actions fail, the StorageException gets wrapped in a NoSuchElementException. Catch those and strip off the NoSuchElementException, then handle the StorageException in the existing way.

The unexpected NoSuchElementExceptions were not being caught anywhere and the scanner thread was dying without rescheduling itself. Added code in PartitionMananger.scan to catch any exceptions that leak out of PartitionScanner and reschedule the scanner unless the host instance is shutting down.

…k is recreated upon a failure (#439)

* message receiver/sender - fix null pointer error and ensure that receive/send link is recreated on a failure.

…nnel for a single connection and improve logging (#443)

* Fix an issue of creating multiple sessions for $management & $cbs for a connection and improve logging

…estChanges

…into mergeLatestChanges