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My questions is: How can I read little endian values from a file stream?

I am trying to read values from a binary file in the WINDOWS platform.
The file includes values of type integer (signed 32-bit integer - 4 bytes) and
double (signed 64-bit IEEE double-precision floating point numbers).
I am using the readInt() and readDouble() functions as defined in the
java.io.* package. However, the values are stored in big and little byte order.
The readInt() and readDouble() functions correctly return only the big endian
values.

My questions is: How can I read the little endian values?

(Gido) wrote in message news:<. com>...
> My questions is: How can I read little endian values from a file stream?
>
> I am trying to read values from a binary file in the WINDOWS platform.
> The file includes values of type integer (signed 32-bit integer - 4 bytes) and
> double (signed 64-bit IEEE double-precision floating point numbers).
> I am using the readInt() and readDouble() functions as defined in the
> java.io.* package. However, the values are stored in big and little byte order.
> The readInt() and readDouble() functions correctly return only the big endian
> values.
>
> My questions is: How can I read the little endian values?

The java.nio (new I/O) package that is new with jdk1.4 has ByteBuffer
and friends that support big and little endian. Use the new I/O
facilities.

Jon

Thanks a lot. Your information was exactly the jump start I needed.
From here on it will be easy.

Thanks
Gido


"Jon A. Cruz" <> wrote in message news:<>...
> Gido wrote:
> > My questions is: How can I read little endian values from a file stream?
>
> Either use someone else's class (like Roedy's LEDataStream
> http://mindprod.com/jgloss/ledatastream.html), or just do it yourself.
>
> Read 4 bytes. Shift and mask. Voila! You're done. It should end up
> looking just like the C/C++ code should.
>
>
> byte tmp[4] = {0,0,0,0};
> in.readFully( tmp );
> int val = ((0x0ff & tmp[0]) << 0)
> | ((0x0ff & tmp[1]) <<
> | ((0x0ff & tmp[2]) <<16)
> | ((0x0ff & tmp[3]) <<24);
>
>
>
> And to read a Double
>
> Read 8 bytes.
> Pack them back into a long. Just like that int code but the values keep
> going.
>
> Then
>
> Double dbl = Double.longBitsToDouble( val );

Roedy

Your web site is a gold mine! Thanks so much for your generous contributions.

Thanks
Gido


Roedy Green <> wrote in message news:<>. ..
> On 5 Jul 2003 11:03:55 -0700, (Gido) wrote or
> quoted :
>
> >I am trying to read values from a binary file in the WINDOWS platform.
>
> see http://mindprod.com/jgloss/endian.html