EClass

EClass is a central metamodel element in the Eclipse Modeling Framework (EMF) and a core part of the Ecore model. It defines a class in a model, specifying its structure, inheritance, and behavior. An EClass belongs to an EPackage and may participate in inheritance by listing one or more supertypes in its eSuperTypes collection. It can be abstract, indicating it cannot be instantiated, or marked as an interface, which represents a protocol rather than a concrete implementation.

An EClass contains structural features, represented as EStructuralFeatures, with EAttribute for data-valued properties and EReference for references to other objects. An EClass can also declare operations via EOperation. When code is generated from an Ecore model, an EClass may map to a corresponding instanceClass, which is the generated Java class.

Instances of an EClass are EObjects. The eClass of an EObject refers to the EClass that defines its structure, and values are stored through the attributes and references defined by that EClass. EObjects can be created dynamically or through generated code, and their lifecycle is tracked by the EMF framework, including notifications and persistence.

In practice, EClasses are used to define domain models within Ecore, enabling code generation, model editing, validation, and serialization. EMF tools can generate editors and runtime support from Ecore definitions, facilitating model-driven development and interoperability across different modeling tasks.