As with many technologies, the basics are easy. The hard part comes when the developer needs to do sophisticated integration, development, and testing as part of an enterprise application. A large enterprise application requires the developer to think of issues that affect the development, scalability and robustness of the application. This presentation will cover the advanced topics described below.

A large enterprise application often will have several sub-projects that each contain their own JPA persistence unit. This opens up a number of questions around how to organize the persistence units and how the code between sub-projects should interoperate. Developers will gain insight into these issues and will see a couple of solutions using live code examples.

Many enterprise applications require integration with an application server's JTA mechanism. JTA integration allows for JPA components to work with container managed transactions and distributed transactions. A typical usage scenario for JPA & JTA is this: read from a database using JPA, perform some business logic, put a message on a queue, write to the database (again using JPA). A JTA transaction allows you to ensure that the entire set of operations is committed or a rollback is performed. In this presentation, the developer will understand the limitations and configuration of using JTA and JPA together ? primarily through real code examples.

Once unit tests are written, developers often gloss over doing fine-grained integration testing just for their persistence layer. Integration testing with JPA means simply one thing: running your JPA components against your target database, for example, Oracle. Overlooking this aspect leads to problems being discovered later in the test cycle (UAT for example) and makes it more difficult to find and fix bugs. This presentation will use live code examples to explain a strategy for getting integration testing for free by reusing unit tests.

Using optimistic locking versus pessimistic locking seems clear cut to most developers. However, a full understanding of the issues with using pessimistic, or datastore, locking is required before making this decision. Developers will get information in the trade offs when using strategy or the other, and how these strategies can be used together with the same persistence unit.

Other tips such as fetch groups, flushing, and caching will be covered as time allows. The presentation will use Weblogic application server, OpenJPA/Kodo, and Spring as the basis for the examples. The presenter has experience with using both Hibernate and OpenJPA so can speak to the portability of these two JPA implementations and its affect on coding.

Performance tuning any application is a black art that can consume much time. Fortunately, Java has many tools that can aid in this effort. There also are a number of basic tips that can help to analyze and fix performance problems. The Java memory model is usually something that you don't need to tune, but for high performance applications it is necessary to tweak. While there are a number of advanced things that can be done to performance tune an application, we'll discover that the simple, basic things are all that are usually needed to make your apps fly.

This session looks at how to setup and run an application with profiling tools and monitoring tools. We'll setup an application to run and put it under heavy load. While running, we'll interactively monitor it and look for problems and how to go about finding and fixing them. We'll also cover the basic issues you should look for when performance tuning. We'll look at memory management and how to tune it appropriately. We'll also look at some of the Java 6 tools available to monitor performance and look at the JVM internals. We'll focus on the simple things that can be done right away and then look at some more advanced tweaks to identify and fix performance issues. Along the way, you'll learn some of the tips and tricks to performance tune.