Re: silly unsigned/signed byte conversion question

From: aspa (aspa_at_foobar.int)
Date: 10/29/03 

Date: Wed, 29 Oct 2003 08:32:45 +0200

Steve Horsley wrote:
> Java has no such type as an unsigned byte.

you're right. i was misleadingly trying to refer to an octet value's
"unsigned" representation as short, int or long.

> <opinion>
> Whoever decided that byte was signed was as mad as a bucket of frogs, but
> the deed is done now, and people will shake their heads in wonder for ever
> more.

and some of us, in confusion too :)

> </opinion>
>
> For efficiency, I guess it is best to accept that bytes are signed, and
> not try to convert to other types at all. If you are working with bytes,
> then work with bytes. -128...+127. Live with it. What's the problem?
> Instead of "if b > 127", use "if b < 0". It can be done.

my original problem was reading 8-bit data from a character stream and
then interpreting that data like in the following peace of code:

        File file = new File("/foo/data.d");
        int len = (int)file.length();
        byte[] buffer = new byte[len];
        FileInputStream fis = new FileInputStream(file);
        int n = fis.read(buffer, 0, len);
        fis.close();
        for(int i=0; i<n; i++) {
            int d = buffer[i] & 0xff;
            System.out.print(Integer.toHexString(d)+" ");
        }
        System.out.println();

this seems to work fine, now.

thanks for the help!

best regards, 

--
	aspa

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