Re: How to convert one text file into one large String?

From:

=?ISO-8859-1?Q?Arne_Vajh=F8j?= <arne@vajhoej.dk>

Newsgroups:

comp.lang.java.programmer

Date:

Sun, 07 Mar 2010 09:52:10 -0500

Message-ID:

<4b93bd90$0$286$14726298@news.sunsite.dk>

On 07-03-2010 02:28, Mike Schilling wrote:

Arne Vajh?j wrote:

On 06-03-2010 13:52, Patricia Shanahan wrote:

Tom Anderson wrote:
...

Absolutely. My code can't possibly work if the length of the file
isn't known ahead of time, so again, the right thing for it to do is
blow up with an exception. Having File.length() return -1 or throw
an exception of its own would achieve that. Returning 0 allows code
written by lazy programmers, such as exhibit A above, to fail
silently, which is bad.

...

Also, zero is inherently ambiguous. It fails to distinguish "The file
exists, has been examined, and is definitely empty." from "Unknown
length.". I think an exception would be much better.

However, I am not sure it would be feasible. The Java API is, in this
sort of area, at the mercy of the operating system.

But it could throw an exception if it was sure that length
did not make sense and return 0 if it were not able
to tell whether it was zero or N/A.

Which still makes 0 ambiguous.

Sure, but it is better to have some ambiguity on 0.1% of
systems than 100%.

Sure portable Java requires it to work everywhere without
exceptions.

But when we start talking about reading from non-files on
unusual operating systems, then I think that carefull
coding and testing is needed anyway.

Anyway, given that all current Windows variants are descendents of NT, which
makes them spiritual descendents of VMS, I'll bet that there are fullly
supported ways to determine the type of "device" an open stream reads from,
and thus whether it has a defined size. I don't know nearly enough about
Linux to even speculate there.

For anything POSIX compliant then S_ISREG(mode) should be fine. That
would apply to Unix/Linux (even though not all of them are officially
certified).

Arne