NeoEMF

Gerson Sunyé

https://sunye-g.univ-nantes.io

Licence

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Icons made by Freepik from Flaticon are licensed by Creative Commons BY 3.0.

NeoEMF: overview

Handle large models with task-specific databases
Lazy-loading
Compliant with the EMF API
- Easy to integrate in existing applications
- EMF-Compatible code generation
Advanced caching (& prefetching strategies)
Efficient XMI importer

NeoEMF: Architecture

NeoEMF: datastores

NeoEMF/Graph

Efficient model traversal using rich query language
Mogwaï framework (OCL to Gremlin translation)

NeoEMF/Map

Fast access to atomic operations
Designed for EMF-API calls

NeoEMF/Column

Transparent model distribution
Concurrent read/write
Distributed model transformations (ATL-MR)

NeoEMF: project website

https://github.com/atlanmod/NeoEMF
Open source project under the Eclipse Public License 2.0

NeoEMF: initialize a new resource

JavaPackage.eINSTANCE.init();
PersistenceBackendFactoryRegistry.register(
			BlueprintsURI.SCHEME,
			BlueprintsPersistenceBackendFactory.getInstance()); (1)

ResourceSet resourceSet = new ResourceSetImpl();
resourceSet.getResourceFactoryRegistry().getProtocolToFactoryMap()
			.put(BlueprintsURI.SCHEME,
					PersistentResourceFactory.getInstance()); (2)

URI uri = BlueprintsURI.createFileURI(new File("<db_path>")); (3)

Resource resource = resourceSet.createResource(uri); (4)

1	Register the Persistence Backend Factory.
2	Create a ResourceSet and register the PersistentResourceFactory
3	Create a new URI to locate a file-based resource.
4	Create the resource.

NeoEMF: persist a resource

ImmutableConfig config = new BlueprintsNeo4jConfig().autoSave().cacheSizes().cacheMetaClasses(); (1)

resource.save(config.toMap()); (2)
// Resource saved in a local Neo4j database
resource.getContents() (3)
// [...]

1	Create a new option configuration (backend-specific).
2	Save the resource.
3	Manipulate the resource by accessing the local database

NeoEMF: modify an existing resource

Load resource using the same option builder.
Navigate its content and perform update operations
Save the resource (automatically done with autosave_ option)

ImmutableConfig config = new BlueprintsNeo4jConfig().autoSave().cacheSizes().cacheMetaClasses();

URI uri = BlueprintsURI.createFileURI(new File("<db_path>"));

resourceSet.createResource(uri)
resource.load(Collections.emptyMap());

// Model manipulation operation (complete EMF API support)
MyClass myClass = (MyClass) resource.getContents().get(0);
myClass.setName("NewName");

// Save the modification in the local Neo4j database
resource.save(config.toMap());

Hands-on time!

Let’s import a Java model, save it in Neo4j and MapDB, and query the database.

NeoEMF: summing up

Select the NoSQL database adapted to a modeling scenario
Transparent EMF integration
On-demand loading