See 
PublishedAPI for packages intended to be used by Plugin and Contrib authors, or 
browse all packages.
See also 
Developing plugins, 
Developer's Bible, 
Technical Overview
 getDefaultValue() → $value 
The default for a select is always the empty string, as there is no way in
Foswiki form definitions to indicate selected values. This defers the decision
on a value to the browser.
 ObjectMethod finish() 
Break circular references.