| Interface | Description | 
|---|---|
| Converter<T> | 
 A  Converteris able to give a representation of an object owned by a Feature to another Feature. | 
| FeatureEntryPoint | Each Feature shall define one entry point that implements this interface. | 
| FeatureStateListener | The listener interface for receiving notifications when the state of a Feature has changed. | 
| Principal | This interface represents and identifies the Kernel or a Feature. | 
| ResourceControlListener | The listener interface for receiving notifications when a Feature is stopped by the Resource Control Manager. | 
| UncaughtExceptionHandler | Deprecated | 
| Class | Description | 
|---|---|
| Feature | A Feature represents an optional part of an application that adds new features and services. | 
| Kernel | The Kernel represents the atomic part of an application. | 
| Module | A  Moduleis either Kernel or a Feature. | 
| Proxy<T> | The superclass of proxy classes. | 
| Enum | Description | 
|---|---|
| Feature.State | A Feature state. | 
| ResourceControlListener.StopCause | A stop cause. | 
| Exception | Description | 
|---|---|
| AlreadyLoadedFeatureException | This exception is thrown if a Feature being loaded has already been loaded. | 
| DeadFeatureException | This exception is thrown by the system when a Feature code has been stopped because it is being uninstalled. | 
| IncompatibleFeatureException | This exception is thrown if a Feature being loaded is not compatible with the current Kernel. | 
| InvalidFormatException | This exception is thrown when a Feature data being loaded has an invalid format. | 
| UnknownFeatureException | This exception is thrown if a Feature being unloaded is unknown. | 
ESR020).