[HBASE-13273] Make Result.EMPTY_RESULT read-only; currently it can be modified

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.98.0, 1.0.0
• Fix Version/s: 1.0.1, 1.1.0, 0.98.12, 2.0.0
• Labels: beginner
• Release Note: The Result.EMPTY_RESULT object is now immutable. In previous releases, the object could be modified by a caller to no longer be empty. Code that relies on this behavior will now receive an UnsupportedOperationException.
• Assignee: Mikhail Antonov
• Reporter: Michael Stack
• Created: 18/Mar/15 18:51
• Updated: 28/Apr/15 19:18
• Resolved: 24/Mar/15 22:48

Description

Again from larsgeorge

Result result2 = Result.EMPTY_RESULT;
System.out.println(result2);

result2.copyFrom(result1);
System.out.println(result2);

"What do you think happens when result1 has cells? Yep, you just modified the shared public EMPTY_RESULT to be not empty anymore."

Fix. Result should be non-modifiable post-construction.