Data Transformation Engine Intelligent Business Integration Reference Guide

Chapter 6 - High-Availability and Load-Balancing Architecture Enterprise JavaBeans
Intelligent Business Integration Reference Guide
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Enterprise JavaBeans
By utilizing an EJB integration approach, maps can be wrapped inside both stateful
and stateless Session beans, and deployed to EJB 1.0, EJB 1.1, and J2EE-
compliant application servers. The application server environments themselves
provide extensive load-balancing and failover between redundant instances of
EJBs running on different physical application servers.
Because map threads are atomic transactions, in the event that a map bean fails,
either because the application server has crashed, or for some other reason, the
map thread’s transaction will be rolled back in its entirety; leaving the sources and
destinations in their original state. Assuming identical map beans are running on a
parallel application server, the source data that was being processed by the
original map bean when it failed will be consumed by the duplicate map bean
running on a different application server.
However, the downside to this approach is that Java programming is required to
create the application layer that interfaces with the map bean.