# Package org.eclipse.viatra.query.runtime.registry

- Interface Summary
  Interface | Description
  --- | ---
  IConnectorListener | Connector listeners are used to receive notifications on addition and removal of query specifications.
  IDefaultRegistryView | The default registry view ensures that the fully qualified name of entries are unique and provides an additional method for retrieving the query group of entries for easy initialization.
  IQuerySpecificationRegistry | The query specification registry is used to manage query specifications provided by multiple connectors which can dynamically add and remove specifications.
  IQuerySpecificationRegistryChangeListener | Listener interface for providing update notifications of views to users.
  IQuerySpecificationRegistryEntry | The query specification registry entry interface can return the identifier of the source that added it to the registry.
  IRegistrySourceConnector | A registry source connector can provide query specifications to listeners (e.g.
  IRegistryView | The registry view is the primary interface for users to interact with the query specifications in an `IQuerySpecificationRegistry`.
  IRegistryViewFactory | This interface can be used to ask the registry to construct specific view instances.
  IRegistryViewFilter | The registry view filter can control which entries are added and removed from an `IRegistryView`.

- Class Summary
  Class | Description
  --- | ---
  ExtensionBasedQuerySpecificationLoader | Loader for the `QuerySpecificationRegistry` based on the query group extensions generated by the VIATRA Query builder.
  QuerySpecificationRegistry | Registry for query specifications that can be accessed using fully qualified names through views.