GlassFish V3 & OSGi
Jerome Dochez and Ludovic Champenois
●
GlassFish team
●Sun Microsystems, Inc.
1

Introduction
• GlassFish, an Open Source application server
built on and with Open Source components :
> Maven 2
– build system
– module description
> Felix
– OSGi module management
> Eclipse Link
– Java Persistence Architecture implementation
• V3 is the third open source release of GlassFish
2

What's new in V3
• Modularity
> platform growth
> choice of technologies rapidly evolving
> based on industry standard OSGi runtime
• Extensible and Embeddable
> not limited to traditional Java EE containers
> can run in any java or native host process
• Service based architecture
> services are defined by contracts and can be easily
substituted
> lazy loading based on usage patterns
3

Modularity in V3
• Modules are great but let's face it, they do nothing just
being modules !
> A good service based architecture is what you need.
• V3 innovation :
> One of the few OSGi enabled application that is completely portable to
any OSGi R4 compliant runtime
> allow any type of container to be plugged in.
> start all containers and services on demand yielding an unmatched
startup time for a Java EE server.
> focus on developer (keeping the already numerous deployer's
features).
4

Modularity
• Kernel
> startup/shutdown sequences
> basic services (deployment)
> configuration reading
• Services
> Cross containers functionalities
– Security, Naming Manager...
– Admin Console
• Containers
> handle user's applications
> independent of each others
5

OSGi R4 Runtime
S
Services
e
c
Applications
Life Cycle u
(Bundles)
r
i
Module
t
y
JDK
OS + Hardware
6

HK2 Module Management Runtime
Services
Applications
Life Cycle
(Bundles)
Module
Bundles Repository
JDK
OS + Hardware
7

HK2 and OSGi
• Use OSGi as the underlying module management
> capable of consuming any OSGi modules
> all GlassFish V3 modules are OSGi modules
• HK2 Provides runtime services on top of OSGi :
Repository management
>
Isolation from OSGi APIs or implementation
>
Services definition and lookup
>
MBeans support
>
Configuration facilities
>
• HK2 is a separate Open Source project
8

Module Management
4. return class loader
1. loadModule
HK2 Services
OSGi
2.Get 3.Install Runtime
Repository
Repository
Repository
9

Services
• GlassFish V3 use extensively Services to identify
extension points like :
> Application Containers (like Web-App, Jruby, Spring)
> Administrative Commands
• Services are :
> implementing an interface
– Java SE style with a META-INF/services file
– OSGi style
– HK2
• Can be stateless or statefull
10

GlassFish V3 Runtime with OSGi
GlassFish V3 modules
Random OSGi Bundle
(OSGi + extra metadata)
Service OSGi
HK2 Service layer Mapper Service Layer
OSGi Bundle management
11

HK2 Service
• Interfaces are declared with @Contract
• Implementations are declared with @Service
• Build system will generate Metadata
automatically
@Contract
public interface Startup {...}
@Service
public class ConfigService implements Startup
{
... }
12

Runtime
• Kernel
> startup/shutdown sequences
> basic services (deployment)
> configuration reading
• Services
> Cross containers functionalities
– Security, Naming Manager...
– Admin Console
• Containers
> handle user's applications
> independent of each others
13

Runtime
Security Config
JRuby/Rails
Web Naming Injection
dispatch
GlassFish Kernel
browser
requests
Grizzly
HK2 Services
OSGi Runtime
Bundles repositories services
14

OnDemand and Extensible
• Pay As you Go
> containers are started when applications are deployed to
them
> startup time is under 2 seconds
• Extensible
> Containers (scripting containers)
> Administration
– Admin Commands
– Configuration
– Admin GUI through plugin
15

GlassFish containers
• Basic Functionalities
> handles certain application types
> started and stopped on demand
• Optional features
> Configuration services (so all containers configuration can be
centrally managed)
> administration commands
> administration console plugins
16

Container Pluggability
Console user
domain.xml
Central Config
Admin Console
C
Container o
GUI Parts
Runtime n
f
Grizzly Adapter i
Admin commands
g
Kernel
client/browser admin invocation
17

OSGi integration
• Module management
> Add, remove, update installed modules
• OSGi as a container !
> Treat OSGi just like the web container, bundles are
deployed to it.
• Converged Applications
> Started investigating Java EE 6 + OSGi converged
applications :
– Dependencies in OSGi
– Lifecycle still governed by Java EE.
18