Distributed OSGi services in JBoss Fuse

JBoss Fuse (Fuse ESB) is a great container featuring Apache Karaf as OSGi container. It has a great feature called Fabric, on which you can start another container efficiently and do provisioning from any container connected in one Fabric. It means that, you can uninstall bundles from in other container from your current container.

Fabric also allows a bundle to publish services and let them be consumed by other bundles. Not just by bundles in the same container, but in other bundles as long as publishers and consumers are connected in one Fabric.

I'm here not to to tell you how to use JBoss Fuse or what it is. But to tell you that it's been hard to find references about how to publish services and consume them in distributed environment. So, I want to share my experience to handle that with blueprint or with Spring DM 1.x.x based on scattered sources of information I have read for weeks.

SELECT ... FOR UPDATE with Spring JDBC

SELECT ... FOR UPDATE is required to lock specific row in database in order to prevent other query thread to read or make changes to the same row. The lock is released once you update the data or commit it.

As a Spring lover, it's hard to find references about implementing the technique in Spring JDBC template. But finally I managed to use it.