Models that implement this interface indicate that
they can be changed. When a model is changed,
it becomes 'dirty'. This state can either be reset
(in case of a 'false alarm' or naturally set to
false as a result of saving the changes.
Models that implement this interface are expected
to be able to save in ASCII file format
This interface is not intended to be implemented by clients.
This interface is not intended to be extended by clients.
Tests whether the model marked as editable can be
edited. Even though a model is generally editable,
it can me marked as read-only because some condition
prevents it from changing state (for example,
the underlying resource is locked). While
read-only models can never be changed, editable
models can go in and out editable state during
their life cycle.
true if model can be modified, false
Tests whether the model has been changed from the last clean
true if the model has been changed and need saving