This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
public interface CommandObject
JavaBeans components that are Activation Framework aware implement
this interface to find out which command verb they're being asked
to perform, and to obtain the DataHandler representing the
data they should operate on. JavaBeans that don't implement
this interface may be used as well. Such commands may obtain
the data using the Externalizable interface, or using an
Initialize the Command with the verb it is requested to handle
and the DataHandler that describes the data it will
operate on. NOTE: it is acceptable for the caller
to pass null as the value for DataHandler.