# Package org.qi4j.api.service

Service API.

See: Description

- Interface Summary
  Interface | Description
  --- | ---
  Availability | Services can implement this interface in order to allow Zest to ask it whether it is currently available for use or not.
  IdentityDescriptor | Identity Descriptor.
  ImportedServiceDescriptor | `ServiceDescriptor` provides meta information of a service.
  ServiceActivation | Convenience interface for simple Service Activation.
  ServiceComposite | All Composites being used to implement Services must extend this interface.
  ServiceDescriptor | `ServiceDescriptor` provides meta informations of a service.
  ServiceFinder | Interface used to query for ServiceReferences.
  ServiceImporter<T> | Import a service from some external source.
  ServiceReference<T> | From a ServiceReference you can access and modify metadata about a service.

- Class Summary
  Class | Description
  --- | ---
  ServiceActivation.ServiceActivator | Service Activator.
  ServiceActivatorAdapter<ServiceType> | Adapter for Service Activator.

- Exception Summary
  Exception | Description
  --- | ---
  DuplicateServiceIdentityException | Thrown when a duplicate service identity is detected.
  NoSuchServiceException | Thrown when no visible service of the requested type is found.
  ServiceImporterException | If a ServiceImporter could not import a service instance it must throw this exception.
  ServiceUnavailableException | Thrown when no available service is found.

## Package org.qi4j.api.service Description

## Service API.