Today, I worked on JRUBY-5541 : Problem with java_import on Android (Ruboto) The issue boiled down to how we turn Java's camelCased method names into Ruby's snake_cased form.

The regex specifies two capturing groups: number 1 is (Java( language)2), which matches Java language language, and number 2 is ( language), which matches a space character followed by language.

In Java, I was surprised by how close the performance was for standard regular expressions to using string primitives. String primitives took 188 ms to process the 100,000 lines. Standard regular ...