Making extensions and adding behavior

The slingshot framework is based on the event-driven architecture. Almost all extensions are made by listening to and publishing events. This is done by utilizing the event driver.

An extension itself is defined by creating a new Guice-module. In particular, the extension needs to define a class that inherits from AbstractSlingshotModule, which in turn extends from AbstractModule. There, you “install” simulation and system behaviors (i.e. listeners and event providers to SimulationDriver and SystemDriver respectively).

Example: Let’s assume you have made an extension to the SimulationDriver and provided subscribers to its events in the SimulationBehavior class. Furthermore, let’s assume you defined it in a plugin called “Extension”. Then you need to create the following class:

public class Extension extends AbstractSlingshotModule {

    @Override
    public void configure() {
        install(SimulationBehavior.class); // <-- Registers the subscribers here
        // Further behavior classes
    }

}

After that, you register this class in the Eclipse’s extension registry, that is, in the plugin.xml the following should be contained:

<extension point="org.palladiosimulator.analyzer.slingshot">
      <slingshot-extension
            module="org.palladiosimulator.analyzer.slingshot.extension.Extension"></slingshot-extension>
      <!-- Further extensions -->
</extension>

As you can see, you can actually define multiple slingshot extensions in the same plugin.

Simulation Behavior extensions (to the SimulationDriver)

In order for the simulation driver to pick up the extension, your class that defines the subscriber handlers needs to implement the SimulationBehaviorExtension interface. This is just a super type and does not define any methods you need to implement. Generally, you should keep subscribers that handle system events and subscribers that handle simulation events apart from each other (see below).

@OnEvent(...)
public class SimulationBehavior implements SimulationBehaviorExtension {

}

System Behavior extensions (to the SystemDriver)

In this case, your class of subscribers should implement the SystemBehaviorExtension.

Model Contribution

See more at UI and Workflow