Instead of copying each character from InputReader to StringBuffer.
Approach: Use StringWriter and jio/copy vs character by character copy. Results from the current patch see a 4-5x perf boost after the jit warms up, with purely in-memory streams (ByteArrayInputStream over a 6MB string).
Screened by: Alex Miller
Is this blocked on a new perf comparison? Should I post one?
This is with an SSD, no idea what the numbers would look like with a spinny disk.
Updated patch to contain ticket id in commit description and provide a few more lines of diff context. No actual changes in the new patch, attribution retained.