Java Reference
In-Depth Information
Migration and integration
This chapter covers
How to access non-OSGi code from within an OSGi
framework
■
How to migrate Java EE web applications into OSGi
■
How Apache Aries can be used to run EJB modules
■
In this topic, we've been looking at how to write
OSG
i applications from scratch. This
is fun, and also useful to know how to do, but it isn't usually the case that you can begin
a brand new project with no existing code. Normally, you'll have application code to
bring with you, either code that needs to be migrated into
OSG
i as part of your proj-
ect, or external services that you need to be able to use from within the
OSG
i frame-
work. Having to bring these sorts of things with you often results in a sinking feeling,
particularly if the code has to keep working in more than one environment.
We're happy to tell you that migrating to
OSG
i is almost certainly not as hard as
you think, and that there are a number of helpful
OSG
i tools and specifications that
make these sorts of requirements possible.
When writing any enterprise application that's going to be put into production,
one of the main tasks is usually to integrate with an existing system or service. It's
unlikely that this service is
OSG
i-based, and there's a decent chance that it isn't
even using Java. Regardless of how the backend service is implemented, there are
techniques you can use.
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