Collections in the Tree Classes
A collection is a set of similar things, like a group of already existing branches or levels. Like everything else in the tree classes, collections have a GUI representation. For example, when you find an existing branch from PeopleSoft Tree Manager, you get a dialog that lets you select the branches you want.
The following screen image is an example of different levels of collections in the Tree classes. And the dialog box data is represented in PeopleCode as the tree level collection.

The following collections are part of the tree classes:
Branch collection
Level collection