Harald Kirsch

genug Unfug.

2015-11-07

Monq.jfa even faster with StringBuilder

As mentioned in the previous article, my revived DFA class library for Java dates back from the time of Java 1.4. It always made heavy use of StringBuffer. Now I found the time to complete replace all instances of StringBuffer with StringBuilder and rerun the performance test reported in the previous article. Here is the table again with the new data:

(all times in seconds)
no. words 3 4 11 17 26 35
$\Delta t$ regex 9 12 28 42 68 82
$\Delta t$ monq 40 47 49 54 55 56
$\Delta t$ monq with StringBuilder 24 24 26 27 29 30

Now the break even, where monq takes over java.util.regex, is already at around 11 words. But I am looking already at some profiling results to see if this can be improved even more.