Re: replace extended characters

From:

Lew <noone@lewscanon.com>

Newsgroups:

comp.lang.java.programmer

Date:

Thu, 10 Feb 2011 19:18:36 -0500

Message-ID:

<ij1v7l$jel$1@news.albasani.net>

VIDEO MAN wrote:

I'm trying to create a java [sic] utility that will read in a file that may
or may not contain extended ascii [sic] characters and replace these
characters with a predetermined character [sic] e.g. [sic] replace ?? with e and
then write the amended file out.

How would people suggest I approach this from an efficiency point of
view given that the input files could be pretty large?

Any guidance appreciated.

Read from a BufferedReader. Write to a BufferedWriter. Process one character
at a time. It won't be efficient unless you are guaranteed a limited
character-set input. The Unicode character space is on the order of 2^24
characters large. "Extended ASCII" is a very tiny subset of that, and also
depends on the character encoding.

If you are certain that the set of possible input characters is small, and
those you wish to substitute even smaller, you can use a lookup table. Use a
'Map<Character,Character>' (will choke on supplementary code points) for
those, and only those, you wish to substitute. If the key is absent, pass the
source character through unchanged. If present, replace with the associated
value.

--
Lew
Ceci n'est pas une fen??tre.
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