Phil Riand and I have created a new project which shows how to use a very powerful feature in IBM Domino 8.5.3. The project contains samples demonstrating how to create threads and Eclipse jobs from XPages to run longer taking operations asynchronously without blocking the XPages user interface or to run scheduled tasks.

Watch this video to see the sample in action (video has no tone).

An example is a task that checks on a scheduled basis for new messages in mailboxes, databases, social networks like Facebook and Twitter, etc. Server side code of an XPages application can then get the latest messages simply by reading the cached information from the task.

All samples in this project use a new feature in Domino 8.5.3. can be used to clone a Domino session of the currently authenticated user. This allows developing threads that run on behalf of a specific user which can use the Domino Java APIs even after the user's HTTP session has expired. which leverages SessionCloner adds additional convenience functionality to set context like the current database, it handles session timeouts, etc.

The Eclipse jobs framework is a powerful framework used by Eclipse rich client developers. Eclipse jobs are essentially threads plus extra functionality like scheduling, progress monitoring, pooling etc. The XPages runtime supports these Eclipse jobs also server side since the necessary plugin comes with the XPages runtime similarly to the OSGi core framework.

In order to run the samples Domino 8.5.3 is needed. The extension library or upgrade pack 1 is only needed to check and display progress in an XPage via the xe:jsonRpcService control.

The Java code for threads and jobs can either be run in a NSF or as plugin. If run in a NSF the java.policy file needs to be changed to grant permissions. For plugins that is not necessary. Check out the project for more details.

These capabilities are advanced capabilities in addition to the 8.5.3 synchronization improvements as mentioned in Karsten Lehmann's blog:
From Phil Riand: "Synchronization no longer happens on the session itself, but on the page instance.  In short, it can now execute 2 different page instances at the same time, while it locks for postback calls to the same page instance and execute them sequentially."
From Karsten: "there will be a new database property called xsp.session.transient. This flag means that unique session objects will be created per request to the server and discarded right after the request ended. This is a first attempt to provide session less mode. If you use this option, then you can create one database with all the services and no synchronization will happen, as each request will have its own session object."

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