Pin the buffer on the output chain

From:

Tom Anderson <twic@urchin.earth.li>

Newsgroups:

comp.lang.java.programmer

Date:

Sat, 20 Feb 2010 11:48:43 +0000

Message-ID:

<alpine.DEB.1.10.1002201134230.28122@urchin.earth.li>

Greets yalls,

Given:

OutputStream out; // this is not buffered

Which is better:

Writer w = new BufferedWriter(new OutputStreamWriter(out));
Writer w = new OutputStreamWriter(new BufferedOutputStream(out));

?

I suppose i'm wondering about (a) whether encoding characters to bytes is
more efficient in bulk than in drips and drabs (and i suppose it must be,
from cache effects alone, but how much so?) and (b) what happens when a
lot of translated characters get written to an unbuffered stream - do the
bytes go in character-by-character (IYSWIM), or in bulk?

The thing that niggles me is that BufferedWriter has a newLine() method,
so i tend to use that for its convenience. But if it's sitting on top of
an OutputStream, then i might need buffering there as well.

I know i could go and read the source code, or do some measurements, and
give me a day or so and i probably will, but this is something i've been
wondering about, so i thought i'd share!

tom

--
Due to my inability to deploy my Taser, I had to resort to punching him
as hard as I could in the face. It is a taught technique. -- PC 5566,
on the arrest of Yassin Omar