1. TM TM
Leverage OSGi in Java EE business
applications with JOnAS
Guillaume Sauthier, Bull SAS
« Demonstrates how OSGiTM can help
building business applications relying on
an OSGiTM Application Server »
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
2. Agenda
I. Why building OSGi applications ?
II.Why do we need Java EE ?
III.Hybrid applications
IV.Best of breed application server
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
3. Why building OSGi applications ?
● Bundles are the building blocks
● Installable, removable, even updatable
● At runtime, dynamically
● Enables application composition (right size)
● Fine control on dependencies
(package version, …)
– Control what you actually use
– Control what you want to expose
– Avoids « classpath hell »
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
4. Why building OSGi applications ?
● OSGi promotes a service oriented approach
● Services are registered under a contract (API) in the
service registry
➢ Loose coupling
● Consumers require services using their contracts
● No hard dependency on a given service provider
● Services are dynamic
● Can come and go at any time
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
5. Why building OSGi applications ?
● Multiple and diverses component models helps
to develop pure OSGi applications
● They still are inter-operable !
● Shield developers from inherent
programmation issues with services
dynamism
● Make your choice after tasting :)
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
6. Why do we need Java EE ?
● Java EE skills are widely known
● Large spectrum: from presentation to data layer
– Servlet, EJB, JPA
● Data integrity
– Transaction (JTA)
● Inter-operability
– With REST and SOAP
(JAX-RS, JAX-WS)
– RMI/IIOP too (CORBA)
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
7. Hybrid applications [1/2]
● Hybrid applications uses the best of the OSGi
and Java EE world
● Well known Java EE programming model
– Ease of development
● A first glimpse at OSGi benefits
– Java EE components can use OSGi
services
– Java EE components are exposed
as OSGi services (EJB)
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
8. Hybrid applications [2/2]
● OSGi based applications can also benefits from
Java EE components
● Servlets / HttpService
● Data access layer
– Connection pooling
– JPA modeling
– Transactions support
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
9. Best of breed application server [1/4]
● JOnAS is it-self built on top of OSGi
● Permits right sized execution platform definition
● SOA principles applied to JOnAS technical services
maximizing testability and overall quality
● Different execution profiles can be defined
– Micro : only the kernel
– Full : All available services
– All the in-between profiles ...
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
10. Best of breed application server [2/4]
● As Java EE implementor, JOnAS is well suited
to provide the OSGi enterprise specifications :
● HTTP Service (Servlet)
● JDBC Service (Data access)
● JTA Service (Transaction)
● JNDI Service (Naming)
● JCA Service (Connector / Resource Adapters)
● JPA Service (High level data access)
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
11. Best of breed application server [3/4]
● JOnAS exposes the OSGi framework to the
Java EE applications
● OSGi services available to Java EE components
Java EE Module OSGi Bundle
EJB 3 Service Implementation
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
12. Best of breed application server [4/4]
● JOnAS exposes the OSGi framework to the
Java EE applications
● EJB business interfaces available to OSGi
Java EE / OSGi Module OSGi Bundle
EJB 3 Service Consumer
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
13. Conclusion
● Java EE programming model is here to stay
● Don't throw away your 'EJB in action' books !
● OSGi is gradually becoming more and more
important
● Apps will benefits from modularity and dynamism
OW2Con 2011, November 23-24, Orange Labs, Paris.
www.ow2.org.
