# Package org.eclipse.viatra.addon.validation.core.api

- Interface Summary
  Interface | Description
  --- | ---
  IConstraint | Interface for a constraint.
  IConstraintSpecification | Interface for a constraint specification.
  IEntry | This interfaces represents a tuple of non-key parameters in a violation of a constraint.
  IValidationEngine | A validation engine is responsible for managing the constraints existing in the scope of a VIATRA Query Engine (e.g.
  IViolation | A violation is set of model elements in an instance model that satisfy the specification of a constraint.
  IViolationFilter | Interface for filtering violations when retrieving them from a constraint or registering for event notifications.

- Class Summary
  Class | Description
  --- | ---
  ConstraintSpecification | Generic implementation of the IConstraintSpecification interface for code buildable constraint specifications.
  ConstraintSpecification.ConstraintSpecificationBuilder | Static builder class provided to construct ConstraintSpecification instances.

- Enum Summary
  Enum | Description
  --- | ---
  Severity | Severity type to define the severity of a violation.