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Concurrency

The default Enterprise Objects core configuration uses a single thread to perform its operations (not including threads in the Java virtual machine), which means that only a single operation within Enterprise Objects can occur at any given moment. More importantly, however, a single application instance by default has only one access layer stack. This means that each user in a single application instance shares the resources for connecting to, fetching from, and committing data to the application’s data sources with the application’s other users.

If user A initiates a fetch while user B’s fetch is being performed, user A’s fetch must wait until user B’s fetch is done. If user B commits many records to a data source while user A is fetching data from that data source, user B’s commit doesn’t occur until user A’s fetch is done. In an application that services multiple concurrent users, you can see that you’ll likely consider instrumenting multithreading in your Enterprise Objects applications.

This chapter discusses threading in Enterprise Objects, including how to instrument multithreading in an Enterprise Objects Application. It is divided into the following sections:

• “Determining Requirements” discusses if and when you should think about implementing concurrency.

• “Maintaining Thread Integrity” discusses your responsibilities when you instrument an application for concurrency.

Contents:

Determining Requirements
Maintaining Thread Integrity

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