RE: [Jython-users] File write and read

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I think you needed to use zeros, not array:

Jython 2.1 on java1.3.1_01 (JIT: null)
Type "copyright", "credits" or "license" for more information.
>>> import jarray
>>> ba =3D jarray.array(64*1024,'b')
Traceback (innermost last):
  File "<console>", line 1, in ?
AttributeError: __len__
>>> ba =3D jarray.zeros(64*1024,'b')
>>>

-Clark

> -----Original Message-----
> From: jyt...@li...=20
> [mailto:jyt...@li...] On Behalf=20
> Of Jeff Emanuel
> Sent: Thursday, February 17, 2005 11:27 AM
> To: Lauri Lehtinen
> Cc: Jython Users
> Subject: Re: [Jython-users] File write and read
>=20
>=20
> Sorry, I answered before reading your entire post.  You=20
> already have a buffered stream in the example below.  Perhaps=20
> you can read a longer array of bytes per iteration of your=20
> loop instead of a single byte.
>=20
> ba =3D jarray.array(64*1024,'b')
> bi.read(ba)
>=20
>=20
> Jeff Emanuel wrote:
> > Because it does a physical I/O operation for every byte.
> > You need to wrap the file streams with buffered streams,
> > for example:
> >=20
> > bi =3D BufferedInputStream(FileInputStream(File(filename)))
> >=20
> >=20
> > Lauri Lehtinen wrote:
> >=20
> >> Setting to use the binary mode worked!
> >>
> >> Does any one know why java variant of this in jython performs very
> >> poorly?
> >>
> >> Here the basic java variant:
> >> ---
> >> from java.net import *
> >> from java.io import *
> >> def copy(filename):
> >>    bi =3D FileInputStream(File(filename))
> >>    bo =3D FileOutputStream(File(filename+".copy"))
> >>    b =3D [1000000]
> >>    while 1:
> >>        l =3D bi.read(b)
> >>        if l =3D=3D -1:
> >>            break
> >>        bo.write(b)              bo.close()
> >>    bi.close()
> >>    return 1
> >>           if __name__ =3D=3D "__main__":          i =3D=20
> raw_input("Give file:")
> >>    copy(i)
> >> ---
> >> That berforms only about 10kB/s, here one that uses buffers and
> >> performs better:
> >> ---
> >> from java.net import *
> >> from java.io import *
> >> def copy(filename):
> >>    bi =3D BufferedInputStream(FileInputStream(File(filename)))
> >>    bo =3D=20
> BufferedOutputStream(FileOutputStream(File(filename+".copy")))
> >>    while 1:
> >>        l =3D bi.read()
> >>        if l =3D=3D -1:
> >>            break
> >>        bo.write(l)              bo.close()
> >>    bi.close()
> >>    return 1
> >>           if __name__ =3D=3D "__main__":          i =3D=20
> raw_input("Give file:")
> >>    copy(i)
> >> ---
> >> This performs about 600kB/s what isn't good at all, that should be=20
> >> much better. I tried also by using static buffer size but that=20
> >> performed even poorly for some reason. Why the performance=20
> is so bad?
> >>
> >> Sincerely,
> >> Lauri Lehtinen
> >>
> >> Kent Johnson wrote:
> >>
> >>> Lauri Lehtinen wrote:
> >>>
> >>>> Hi,
> >>>>
> >>>> I just noticed this, when I have this kind of code:
> >>>> ---
> >>>> def copyFile(filename):
> >>>>    bi =3D open(filename)
> >>>>    bo =3D open(filename+'.copy', 'w')
> >>>>    b =3D 1000000
> >>>>    while 1:
> >>>>        l =3D bi.read(b)
> >>>>        if len(l) =3D=3D 0:
> >>>>            break
> >>>>        bo.write(l)
> >>>>    bo.close()
> >>>>    bi.close()
> >>>>    return 1
> >>>>           i =3D raw_input("Give file:")
> >>>> copyFile(i)
> >>>> ---
> >>>> and e.g. copy mp3 file with it the .copy mp3 file is=20
> somehow mixed
> >>>> and not working as it should, but when I run this with=20
> plain python=20
> >>>> it works just as it should. How to fix or workaround=20
> this? Is thus=20
> >>>> known bug?
> >>>
> >>>
> >>>
> >>>
> >>> Maybe you need to use binary mode?
> >>>    bi =3D open(filename, 'b')
> >>>    bo =3D open(filename+'.copy', 'wb')
> >>>
> >>> How do the two files differ?
> >>>
> >>> Kent
> >>>
> >>>>
> >>>> I have tried to make the same using java's FileInputStream and
> >>>> FileOutputStream but then the performance is then very=20
> bad (about=20
> >>>> 500kB/s). Is that also known issue?
> >>>>
> >>>> Sincerely,
> >>>> Lauri Lehtinen
> >>>>
> >>>>
> >>>>
> >>>> -------------------------------------------------------
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> >>>
> >>>
> >>>
> >>>
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> >>>
> >>>
> >>
> >>
> >>
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> _______________________________________________
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> >> Jython-users mailing list
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> >=20
> >=20
> >=20
> > -------------------------------------------------------
> > SF email is sponsored by - The IT Product Guide
> > Read honest & candid reviews on hundreds of IT Products from real=20
> > users. Discover which products truly live up to the hype. Start=20
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http://ads.osdn.com/?ad_id=3D6595&alloc_id=3D14396&op=3Dclick
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> > https://lists.sourceforge.net/lists/listinfo/jython-users
>=20
>=20
> -------------------------------------------------------
> SF email is sponsored by - The IT Product Guide
> Read honest & candid reviews on hundreds of IT Products from=20
> real users. Discover which products truly live up to the=20
> hype. Start reading now.=20
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>=20
> _______________________________________________
>=20
> Jython-users mailing list
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>=20