What are Simple Dynamic Modules?

Simple Dynamic Modules (SDM) for Groovy is a module system based on Maven that provides a way to achieve dynamic modularization of applications and services on the JVM platform using Maven artifacts and repositories.

SDM aims to be for Groovy and the Java platform what RubyGems is to the Ruby language.

Combined with the powerful meta programming capabilities of Groovy, SDM is the perfect tool to package and use DSLs (just like the way RubyGems does). For example, you can use the Apache Camel DSL right away like this:

``` require 'org.sdm:camel'

routes { errorHandler noErrorHandler()

from('cxfrs://bean://rsServer') { process new DebugProcessor() to 'bean://helloService' } } ```

SDM is compatible with Maven artifacts and repositories and is an alternative to the OSGI framework.

Maven dynamic modules

With SDM, a maven artifact becomes a dynamic module out of the box!

Dynamic modules
The dynamic module system is fully integrated with maven build system and repositories.

Module activation

Modules can be started, stopped and restarted dynamically either from the command line or the JMX console.

A module can define a ModuleMain script containing lifecycle callbacks that will be automatically called by the SDM runtime.

For example: ``` package org.sdm.http ... server = new_('org.mortbay.jetty.Server') server.start() serviceRegistry.register('http.server', server) ... def stop() { server.stop() }

```

Runtime dependency management

The require method can be used to dynamically load a module.

Example using the groovy language: require 'org.sdm:cxf' require group: 'mygroup', module: 'mymodule', revision: '1.0' etc...

Runtime versioning of modules

Multiple versions of the same module can run in the same JVM process.

Dynamic module versioning

SDM is similar to OSGI but uses Maven artifacts directly and does NOT require the use of custom bundles.

Service activation

When starting, a module can start and publish services to the SDM global service registry.

Application server

SDM comes with a set of modules containing technical services, that are started/stopped on demand at runtime and constitute an application server all together.

JEE integration

It is not always easy to switch to a new platform, therefore SDM can be easily integrated to a JEE server. A SDM platform can be launched over a JEE platform or a servlet container. In this case, the SDM servlet can be setup and work as an adapter between the servlet container and the SDM HTTP service.

What's next?

SDM is very simple to use.

See how to setup SDM and launch the demo application module here.