Many of the option classes in jclouds have a "NONE” field that cleverly creates a default instance of the class containing no options. Can anyone enlighten me on the history of this pattern and why this is necessary?
My best guess is that this may have been an instance of the Null Object pattern, so that you can do things like:
public X list() {
return list(Options.NONE);
}
and can then implement the version *with* options without having to
check for null options etc.
ap
