OLGA is a generic tool aiming to accelerate the adoption of the Semantic technology such as the Ontology Web Language OWL and the Resource Description Framework RDF, and Json Linked Data Jsonld in the Internet Of Things development.

OLGA complements existing OWL, RDF, and Jsonld serializers such as Jackson-Jsonld in Java and RDF4J or RDF Object Relational Mappers such as RomanticWeb in C# and RDFAlchemy in Python.

OLGA takes as input the following:

1. One or more Ontologies
2. A paramter indicating the dependency of the generated library.
   1. Jackson-Jsonld - Java
   2. RomanticWeb - C#
   3. RDF4J - Java
   4. RDFAlchemy - Python

The output of OLGA is a generated library ready to be used by IoT developers. The generated library is conform to the ontology and is dependent on available serializers and ORMs in various languages (C#, Java, and Python for now) as shown below. .

SAREF the Smart Appliances REFerence Ontology depends on the Time Ontology. Once merged the two ontologies have around 200 Classes and Individuals.

The following sections contain the generated code by OLGA of SAREF.ttl and Time.ttl Ontologies. Each section provides the following:

1. Packaged generated library in .dll, .whl, and .jar
2. Generated source code in C#, Python, and Java
3. Generated ontology instance (A-Box) of an instantiation SAREF example
4. An instantiation and usage examples for each of the generated SAREF libraries (Jackson-Jsonld and RomanticWeb). The examples demonstrate how any IoT developer can import the generated packages and use them in his development without any knowledge regarding ontologies. The provided examples show the instantiation of a SAREF temperature sensor with a measurement temperature in degree Celsius, and other information such as the manufacturer and the model number.

1. RomanticWeb-C#
2. Jackson-Jsonld-Java
3. RDF4J-Java
4. RDFAlchemy-Python