Summary

As you've seen in this chapter, legacy and batch integration, although simplistic, can sneak in a few performance "curveballs." Regarding batch components, it's worth remembering that although it's important to keep it simple, batch components aren't always the best method of servicing unusual requirements.

Developing a lot of these batch type components within Java, although it may take longer and will operate slightly slower with a one-to-one component view, will, at the end of the day, operate less efficiently when the system is under load. Keeping everything operating as a J2EE Java application means that the WebSphere containers are in charge and are doing what they're designed to do.

Legacy components are slightly different. Most of the common legacy integration technologies available come with best practices and well-proven Java Application Programming Interfaces (APIs). This provides a tighter level of integration with the WebSphere core engine and ultimately provides better performance overall.

The bottom line is this: Follow the rules discussed in Chapters 6 “9 when I talked about topologically architectures and high-availability concepts and integrate the key points from this chapter into your legacy systems interface design.