[XW-653] TextParseUtil is slow (patch attached)

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0, 2.0.1, 2.0.2, 2.0.3, 2.0.4, 2.0.5, 2.0.6, 2.0.7, 2.1, 2.1.1
• Fix Version/s: 2.1.2
• Flags: Patch
• Assignee: Rainer Hermanns
• Reporter: Joachim Ansorg
• Created: 15/Jul/08 08:27
• Updated: 18/Dec/08 14:30
• Resolved: 18/Dec/08 14:30

Description

Hi,

I recently profiled a Struts2 application I'm working on. XWork's TextUtil.translateVariables used up about 30% of the complete time. That's quite a lot!

So I did benchmarked that method and patched it a little.

I was able to cut down the time from 38.9s to 26.6s on my system, using a simple benchmark which executed the tests in TextUtilTest in a loop. That's about 31.7%.

The + operator for String creates an implicit StringBuilder object each time. That method used that quite a lot (in the inner while() loop).

I just made sure that the String concatenations are not in the inner loop.

I also replaced simple String concatenations with String.concat.

This just creates a new String instead of a StringBuilder and then StringBuilder.toString, which then creates a new string.

I think further optimization is possible, but not as easy as this path.

Would be cool if you could include it in the next version.