| AbstractResource serves the same purpose as java
ResourceBundle/PropertyResourceBundle.
Each Resource belongs to a resource tree, indicated by the
path attribute.
AbstractResource uses a Factory pattern rather than a single static method to
load itself given an abstract string path.
One advanced feature which should not be used outside the core GWT system is
that resources can have more than one parent, for instance pets_en_US could
have pets_en as one parent and animals_en_US as another. The alternative
parents have lower precedence than any primary parent. Each alternative
parent is associated with a separate resource tree.
| 