[UIMA-4669] UV3 Internal - change some APIs to return more specific subclass

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: Core Java Framework
• Epic Link: UIMA Version 3
• Assignee: Unassigned
• Reporter: Marshall Schor
• Created: 29/Oct/15 15:13
• Updated: 15/Sep/20 17:33

Description

A method which always returns an instance of class C can be specified in the API to return an instance of C or any of its superclasses. Change the return type to be C instead of one of the superclasses, because

• the user who is expecting the supertype will still work and cost nothing (a "Widening Reference Conversion")
• users who need the subtype would otherwise need to cast back to the subtype - which is a runtime check (unless the JIT can optimize this away).