Classes
 ClassDescription
 CommandComplete API for configuring methods which should be invoked when a matching asynchronous command execution has been completed.
 CommandError API for configuring methods which wish to be invoked when a matching asynchronous command execution aborts with an error.
 CommandResult API for configuring methods which should be invoked when the result of a matching asynchronous command execution has been received.
 CommandStatus API for configuring properties that serve as a flag for indicating whether any matching asynchronous command is currently active.