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Re: DataInputStream

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On Tue, 4 Oct 2011 22:34:56 -0700 (PDT), bob <bob@coolgroups.com>
wrote, quoted or indirectly quoted someone who said :

>I want to use DataInputStream to read into a float[].  Anyone know how
>to do this?

In Java, with DataInputStream you have to think in terms of reading
primitives, not records as you would in C++ or COBOL.

You would read a count followed by n floats, one field at a time. Ask
http://mindprod.com/jgloss/fileio.html to generate you the code.

You can logically read and write entire objects including arrays with
dependent contents using serialization.  See
http://mindprod.com/jgloss/serialization.html
again http://mindprod.com/jgloss/fileio.html will generate you sample
code.

Part of the reason is Java as WORA. The I/O has to work whether the
machine is internally in big or little ended.  the run time has to
convert on a field by field basis.  Java can't treat objects/records
as just a blob of bytes the way earlier machine-dependent languages
can.

It is a lot easier to let java determine the exact binary layout of
files rather that trying to read some bizarre format created
elsewhere.  Then you have to read byte by byte with an InputStream.


-- 
Roedy Green Canadian Mind Products
http://mindprod.com
It should not be considered an error when the user starts something
already started or stops something already stopped. This applies
to browsers, services, editors... It is inexcusable to 
punish the user by requiring some elaborate sequence to atone,
e.g. open the task editor, find and kill some processes.

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DataInputStream bob <bob@coolgroups.com> - 2011-10-04 22:34 -0700
  Re: DataInputStream Robert Klemme <shortcutter@googlemail.com> - 2011-10-05 08:02 +0200
    Re: DataInputStream bob <bob@coolgroups.com> - 2011-10-04 23:17 -0700
      Re: DataInputStream Robert Klemme <shortcutter@googlemail.com> - 2011-10-05 00:07 -0700
        Re: DataInputStream bob <bob@coolgroups.com> - 2011-10-05 07:17 -0700
          Re: DataInputStream markspace <-@.> - 2011-10-05 08:27 -0700
          Re: DataInputStream Patricia Shanahan <pats@acm.org> - 2011-10-05 08:38 -0700
          Re: DataInputStream Robert Klemme <shortcutter@googlemail.com> - 2011-10-05 08:58 -0700
            Re: DataInputStream Lew <lewbloch@gmail.com> - 2011-10-05 14:52 -0700
              Re: DataInputStream Patricia Shanahan <pats@acm.org> - 2011-10-05 15:15 -0700
              Re: DataInputStream Robert Klemme <shortcutter@googlemail.com> - 2011-10-06 00:11 -0700
                Re: DataInputStream Lew <lewbloch@gmail.com> - 2011-10-06 07:08 -0700
                Re: DataInputStream Patricia Shanahan <pats@acm.org> - 2011-10-06 07:49 -0700
          Re: DataInputStream Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-10-05 21:16 -0400
      Re: DataInputStream Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-10-05 08:12 +0000
        Re: DataInputStream bob <bob@coolgroups.com> - 2011-10-05 07:12 -0700
  Re: DataInputStream Roedy Green <see_website@mindprod.com.invalid> - 2011-10-06 02:48 -0700

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