Pivot Standalone API Configuration

Pivot Standalone API Configuration

If you use Eclipse OCL within Eclipse you should find that the appropriate registrations are provided for you automatically by the plugin registration mechanisms.

However if you use Eclipse OCL outside Eclipse, for instance in JUnit tests, you should initialize the appropriate language support using at least one of.

org.eclipse.ocl.xtext.completeocl.
    CompleteOCLStandaloneSetup.doSetup();  // *.ocl
org.eclipse.ocl.xtext.essentialocl.
    EssentialOCLStandaloneSetup.doSetup(); // *.essentialocl
org.eclipse.ocl.xtext.oclinecore.
    OCLinEcoreStandaloneSetup.doSetup();   // *.ecore, *.oclinecore
org.eclipse.ocl.xtext.oclstdlib.
    OCLstdlibStandaloneSetup.doSetup();    // *.oclstdlib

Failure to initialize language support usually results in one of the following diagnostics.

No OCL Standard Library content available
No 'XXX' type in the OCL Standard Library

If you want to use UML models, the optional functionality must be activated.

org.eclipse.ocl.pivot.uml.UMLStandaloneSetup.init();  // *.uml

The following initializations that were once recommended should happen automatically.

org.eclipse.ocl.pivot.OCL.initialize(resourceSet);
org.eclipse.ocl.pivot.uml.internal.es2as.
    UML2AS.initialize(resourceSet);
org.eclipse.ocl.pivot.model.OCLstdlib.install();
org.eclipse.ocl.pivot.internal.delegate.
    OCLDelegateDomain.initialize(resourceSet);
org.eclipse.ocl.pivot.internal.resource.
    StandaloneProjectMap.getAdapter(resourceSet);

These are elaborated on below.

Models

For the Pivot metamodel, the required registrations should be provided by invoking org.eclipse.ocl.pivot.OCL.initialize(ResourceSet). This initialization ensures that *.ecore is understood.

If *.uml support is also required, invoke org.eclipse.ocl.pivot.uml.internal.es2as.UML2AS.initialize(ResourceSet) as well. This initialization ensures that *.uml is understood and that standard pathmap: locations are resolvable. It also invokes org.eclipse.uml2.uml.resources.util.UMLResourcesUtil.init(ResourceSet) to ensure that all Eclipse and OMG UML namespaces and extensions are registered.

OCL Standard Library

If you want to use the default OCL Standard Library you should invoke org.eclipse.ocl.pivot.model.OCLstdlib.install() which installs a compiled shareable form of /org.eclipse.ocl.pivot/model/OCL-2.5.oclstdlib.

If you want to use an alternate library examine the code for the standard installation above, and if you want to compile your library examine the /org.eclipse.ocl.examples.build/src/org/eclipse/ocl/examples/build/GenerateOCLstdlibModel.mwe2 launcher for the /org.eclipse.ocl.examples.build/src/org/eclipse/ocl/examples/build/xtend/GenerateOCLstdlibXtend.xtend Xtend template.

Note that the library is extensible and importable so you may import your own library that in turn imports the standard library.

If you neglect to install an OCL Standard Library, you get the error “No OCL Standard Library content available”. If you provide a custom library that fails to meet the miinimal requirements of defining the basic library types (e.g. Boolean, Set, Tuple) and methods (e.g. OclAny::“=”) you get an error such as “No 'Boolean' type in the OCL Standard Library”.

Pivot Delegates

If you have textual OCL embedded within Ecore models you need to register the EMF delegates so that EMF gets, calls or validates dispatch the embedded OCL to the OCL delegates. The required registrations may be provided by OCLDelegateDomain.initialize(ResourceSet) from the org.eclipse.ocl.pivot.internal.delegate package.

This may be invoked with a null argument to install the registrations in the global EPackage.Registry rather than a specified local registry.

If you neglect to register delegates before generated EMF classes are initialized, you may get an NPE or an error of the form "An exception occurred while delegating evaluation of the ..."

Xtext Parsers

If you want to be able to convert any textual form of OCL to its internal pivot form you need to initialize the relevant parser.

*.ocl Complete OCL documents are initialized by CompleteOCLStandaloneSetup.doSetup().

*.oclinecore metamodels are initialized by OCLinEcoreStandaloneSetup.doSetup()

*.oclstdlib OCL Standard Library definitions are initialized by OCLstdlibStandaloneSetup.doSetup().

*.ecore, *.essentialocl, *.uml files or general use of the query API is initialized by EssentialOCLStandaloneSetup.doSetup().

Each of the above ensures that everything that it requires is installed. The various set ups can be found in one of the following packages:

org.eclipse.ocl.xtext.completeocl.
org.eclipse.ocl.xtext.essentialocl.
org.eclipse.ocl.xtext.oclinecore.
org.eclipse.ocl.xtext.oclstdlib.

platform:/plugin and platform:/resource URIs

If you want to be able to use platform:/plugin/... or platform:/resource/... URIs in a standalone configuration you need to configure the EMF package and URI map registries appropriately. This is a costly activity that involves scanning the classpath and exploiting the content of any plugin.xml and MANIFEST.MF files that are found.

org.eclipse.ocl.pivot.internal.resource.StandaloneProjectMap.getAdapter(resourceSet);

creates a StandaloneProjectMap to cache all the scan results, initializes the ResourceSet and installs itself as an adapter on the ResourceSet so that it can be retrieved again if needed. Users are strongly recommended to ensure that a single StandaloneProjectMap is shared by all clients and so avoid incurring the classpath scan cost more than once.

(The StandaloneProjectMap has no OCL-specific functionality; it just cures a major problem in the standalone usage of EMF.)

Classpath

If your standalone environment supports OSGI bundles, as will be the case when you use Eclipse to launch a JUnit test or a transformation, the required plugin dependencies are easily configured in the MANIFEST.MF using JDT quick fixes, or the Manifest editor.

For a totally standalone Java launch, you must identify the exact spelling of each JAR that you require and identify it on your Java classpath. The Eclipse JARs may be found in the plugins folder adjacent to your eclipse.exe. So you may need org.eclipse.ocl.common_1.0.0.v20120516-1543.jar amongst many others. The required JARs can be recursively determined by looking at the Class Not Found Exceptions from the Java launch and locating the plugin with a similar name prefix. This is very tedious and has to be repeated each time you upgrade, so don’t do it. Use OSGI. However if you must, the following dependency trees may provide some clues.

The dependency tree for the basic parsing and evaluation is:

org.eclipse.ocl.common
  org.eclipse.ocl.pivot
    org.eclipse.ocl.xtext.base
      org.eclipse.ocl.xtext.essentialocl
        org.eclipse.ocl.xtext.completeocl
        org.eclipse.ocl.xtext.oclinecore
        org.eclipse.ocl.xtext.oclstdlib

Additionally the UI requires

org.eclipse.ocl.common.ui
  org.eclipse.ocl.examples.markup
    org.eclipse.ocl.examples.markup.ui
      org.eclipse.ocl.xtext.essentialocl.ui
        org.eclipse.ocl.xtext.completeocl.ui
        org.eclipse.ocl.xtext.oclinecore.ui
        org.eclipse.ocl.xtext.oclstdlib.ui
        org.eclipse.ocl.examples.xtext.console
          org.eclipse.ocl.pivot.ui

You may also need the Xtext, EMF, MWE, Orbit plugins and their dependencies

com.google.guava
com.google.inject
org.apache.log4j
org.eclipse.emf.common
  org.eclipse.emf.ecore
    org.eclipse.emf.codegen
    org.eclipse.emf.ecore.xmi
org.eclipse.xtext
  org.eclipse.xtext.common.types
    org.eclipse.xtext.common.types.ui
  org.eclipse.xtext.ui
    org.eclipse.xtext.ui.shared
  org.eclipse.xtext.util