Exception class for attempts to generate invalid DDMS components.
The underlying data is stored as a ValidationMessage, which allows locator information to be set on it. Because InvalidDDMSExceptions are singular (one is thrown) while validation warnings are gathered from subcomponents and merged into a master list, we modify the exception itself when adding parent locator information.
Since a component is not nested in another component at the time of instantiation, it has no parent when a validation exception is thrown. Therefore, the locator info will always consist of the single element whose constructor was called.
@author Brian Uri!
@since 0.9.b