[SPARK-28066] Optimize UTF8String.trim() for common case of no whitespace

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.4.3
• Fix Version/s: 3.0.0
• Component/s: Spark Core
• Assignee: Sean R. Owen
• Reporter: Sean R. Owen
• Created: 16/Jun/19 14:26
• Updated: 17/Jun/19 15:54
• Resolved: 17/Jun/19 15:50

Description

UTF8String.trim() allocates a new object even if the string has no whitespace, when it can just return itself. A simple check for this case makes the method about 3x faster in the common case.

Issue Links

• links to: GitHub Pull Request #24884