Autodescripted modules

This article explains how to define and instanciate generic Java modules.

Use case

You can see autodescripted modules as classes which you can instanciate.

Normally a Java module is just a jar file which is accessed through the module configuration.

In that case all of the following definitions must be defined in the configuration:

• The Module path which is the class which will be instanciated for the Module at the initialization of the framework
• The Module entry points which are the methods which will be called for each notification
• The Services interface for the module
• The services configuration for the Services used in the application
• The types configuration for the Types used in the application

However it is possible to specify all these elements in the jar file Manifest. You can consider an autodescripted module as a class which you can instanciate wherever you need to. For example, in the example below, an InertialNavSystem module is defined once in a jar file, and used for two instances:

Defining an autodescripted module

To define an autodescripted module, you just have to create a jar file containing the code, and specify the Manifest for this module, which will define:

• Mandatory: The application configuration. See Defining the module configuration
• Optional: The services configuration for the Services used in the module
• Optional: The types configuration for the Types used in the module
• Optional: The module version

Interfaces declaration

Interfaces are declared exactly as for a regular module. Note that by default:

• If no interfaces are specified for a Module instance, the interfaces declared for the autodescripted module will be used
• if interfaces are specified for a Module instance, these interfaces will be used rather than those specified for the autodescripted module

Using an autodescripted module

Module instances are Java modules which are instances of autodescripted modules. They don't have any implementation because they instanciate their associated autodescripted module.

Example

Simple example

The following definition specifies the manifest for an autodescripted module:

      Modules: org/da/protoframework/tacticalenv/resources/application.xml
      Types: org/da/protoframework/tacticalenv/resources/types.xml
      Services: org/da/protoframework/tacticalenv/resources/services.xml

With the following specification for the application.xml applications configuration:

      <application name="publishAppli">
          <modules>
             <module name="PublishModule" >
                <implementation path="org.da.samples.protoframework.publish.PublishModule" >
                   <initEntryPoint method="init" />
                   <defaultReceiveEntryPoint method="subscribe" />
                </implementation>
                <interfaces>
                   <eventReceived service="event1"/>
                   <eventSend service="event2"/>
                </interfaces>
             </module>
          </modules>
      </application>

If the autodescripted module is defined in the MyModule.jar file, we can use this autodescripted module in the following instance:

      <application name="MyAppli">
        <deployment>
          <lib url="MyModule.jar" />
        </deployment>
      </application>

A more complex example

The tacticalEnv model Application allows to maintain a data store from datas provided by a tacticalEnv Application.

      <applications>
         <application name="tacticalenv">
            <deployment>
               <lib url="tacticalEnv.jar" />
               <lib url="tacticalEnvModel.jar" />
            </deployment>
         </application>
      </applications>