[LANG-136] [lang] Make StopWatch validate state transitions

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.1

Environment

Operating System: other
Platform: Other

• Bugzilla Id: 29163
• Assignee: Unassigned
• Reporter: Tim O'Brien
• Created: 24/May/04 04:20
• Updated: 16/Oct/13 08:54
• Resolved: 16/May/06 12:25

Description

Per Henri's email to commons-dev on 5/23/2004, StopWatch currently let's you
call split() or stop() multiple times. StopWatch could benefit from some
validation, to make sure the following validation occurs:

1. split(), suspend(), or stop() cannot be invoked twice.
2. unsplit() may only be called if the watch has been split()
3. resume() may only be called if the watch has been suspend()
4. start() cannot be called twice.

Whomever takes on this burden should take some time to draw a simple state
transition diagram and put it in the JavaDoc.