jython-users — Discussion of and questions about using Jython

Re: [Jython-users] exec and globals

[Ype K. <yk...@xs...>]

Frank,

>If anyone will confirm this is the best way to use exec and globals, I would
>certain appreciate your feedback.
>
>The goal is to have the Jython equivalent of server-side include files where
>one script calls another and can share variables. In an experiment I created
>two files:
>
>exec_example.py
>
>def makethecall:
>    i=100
>    exec open("included.py").read()
>    print "j=", j
>makethecall()
>
>
>included.py
>
>j=101
>print "i=", i
>
>By running exec_example I see:
>
>i=100
>j=101
>
>Is this the best way to have scripts calling other scripts and returning
>results?

This illustrates that the global namespace passed to exec is the local
namespace of the makethecall function.
You can have more control over the namespaces passed to exec by passing
these as arguments, too. My guess is that you are going to need this.
In this particular example I think I'd prefer to use execfile(), but
that is rather minor.

You could also note that:
- the __name__ variable in the executed code will have the value of the
  __name__ variable at the exec call, which might not be desirable.
- the function makethecall is defined when included.py is exec'ed,

There are a few other things that are normally provided by jython
itself for the code it executes that you might want to consider:

In case you want to control import's in exec'ed code:
- sys.modules might change during the exec when the executed code imports
  other modules.
- neither exec nor execfile does any module administration in
  sys.modules. You can do this yourself by (temporarily) adding
  a new.module() to sys.modules.
In case you want more control over imports in executed code you'll need to
control sys.path too, as it determines the places from which modules can
be loaded.

The exec'ed code might throw
- a jython exception. You might want to catch it.
- a java exception that you cannot catch in jython.

The exec'ed code might not return. This is rather hard to control,
but it is possible in jython by using a (deprecated) java call to stop
the thread doing the exec. Fortunately the python language does not
encourage writing endless loops.

The nice thing about python/jython is that you can control almost all
of these aspects when using exec or execfile.
The downside is off course that you might have to write the code to do
some of this. If you'd like to see an example, let me know.

Regards,
Ype

Re: [Jython-users] Multithreading in Jython

[Frank C. <fc...@pu...>]

Raj: From what I've seen and read about Jython's threading, I think Java
threads are the better way to go. In your architecture you would write Java
modules that implements Thread and handles all the get/set methods needed to
set-up and operate the JDBC connection. Jython would instantiate your JDBC
thread (or multiple threads to check scalability) and respond to result sets
returned.

I think you may find what you're wanting to build in Load, an open-source
project I maintain. I am in the process of moving Load to use Jython as a
script language. Details are at: http://www.pushtotest.com.

And, of course, PushToTest has consulting solutions to add functions needed
to test your application. Let me know if we can help.

-Frank

-- 
Frank Cohen, founder, PushToTest, www.pushtotest.com, phone: 408 374 7426
Come to PushToTest for Load, a free open-source tool for performance and
scalability testing and data migration.

> From: R Datta <rd...@cr...>
> Date: Thu, 20 Sep 2001 12:11:40 -0700
> To: jyt...@li...
> Subject: [Jython-users] Multithreading in Jython
> 
> Hi all,
> 
> I am working on a program to simulate stress testing (large number of
> users) on JDBC connections. I would like to multithread the JDBC operations.
> 
> I would appreciate some input (samples, tips etc) with anyone that has
> tried multithreading within jython scripts.
> 
> Thanks
> Raj
> 
> Thanks
> Raj Datta
> Professional Services                           Direct   : 408-530-4932
> CrossAccess Corp                                Cell       : 408-316-5473
> 2900 Gordon Ave #100                       Fax       : 408-735-0328
> Santa Clara CA 95051                         Email   : rd...@cr...
> 
> 
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users

Re: [Jython-users] Basic newbie questions: threads, spawning apps, SSL

[Frank C. <fc...@pu...>]

I've been looking into the OpenSSL project. Do you know if they are the
providers of the JDK 1.4 SSL?

-Frank

-- 
Frank Cohen, founder, PushToTest, www.pushtotest.com, phone: 408 374 7426
Come to PushToTest for Load, a free open-source tool for performance and
scalability testing and data migration.

> From: Ted Berg <te...@et...>
> Reply-To: te...@et...
> Date: Fri, 21 Sep 2001 11:45:41 -0700
> To: Ype Kingma <yk...@xs...>, jyt...@li...
> Subject: Re: [Jython-users] Basic newbie questions: threads, spawning apps,
> SSL
> 
> On Friday 21 September 2001 12:03, Ype Kingma wrote:
> 
> 
>>> 3) Will someone point me in the right direction to do SSL in Jython.
>> 
>> That's more difficult: in jython you're limited to what java can
>> offer you, and I don't recall having secure sockets in java.net.
>> You might try to find any java implementation of secure sockets.
>> 
> 
> As of 1.4 SSL is supported in java.  I haven't played with it myself, so
> that's all I can tell you.
> 
> JDK1.4 beta 2 is available from javasoft.com, but is not yet ready for public
> consumption.  Personally, I've had no trouble with it.
> 
> 
> ted
> 
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users

Re: [Jython-users] Why Memory Usage Increase with a PythonInterpreter and running eval in aloop?

[Samuele P. <pe...@in...>]

Hi.

> Can anyone explain why the attached simple Java program which creates one
> PythonInterpreter and then does an eval in a continuous loop using so much
> memory on Windows 2000 and Linux?  Is it a Java problem or a Jython
> problem?  Can it be fixed?
Given your data it seems an IBM Java problem ;)
Seriously the only potential memory leak that I see is with the all
classes dynamically loaded if the VM does not discard them at some point,
which is not mandatory (see the JLS) but should be a reasonable behavior ;)
With the Sun HotSpot you have a -verbose:class option. Don't know
about the IBM VM. Here is what you see running your code:

a bunch of dynamical class loading:
[Loaded org.python.pycode._pyx4667]
[Loaded org.python.pycode._pyx4668]
[Loaded org.python.pycode._pyx4669]
[Loaded org.python.pycode._pyx4670]
[Loaded org.python.pycode._pyx4671]
[Loaded org.python.pycode._pyx4672]
[Loaded org.python.pycode._pyx4673]
[Loaded org.python.pycode._pyx4674]
[Loaded org.python.pycode._pyx4675]
[Loaded org.python.pycode._pyx4676]
[Loaded org.python.pycode._pyx4677]
[Loaded org.python.pycode._pyx4678]
[Loaded org.python.pycode._pyx4679]
...
[Unloading class org.python.pycode._pyx6636]
[Unloading class org.python.pycode._pyx6538]
[Unloading class org.python.pycode._pyx6593]
[Unloading class org.python.pycode._pyx6598]
[Unloading class org.python.pycode._pyx7066]
[Unloading class org.python.pycode._pyx7002]
[Unloading class org.python.pycode._pyx6510]
[Unloading class org.python.pycode._pyx6785]
[Unloading class org.python.pycode._pyx6621]
[Unloading class org.python.pycode._pyx6892]
[Unloading class org.python.pycode._pyx6863]
[Unloading class org.python.pycode._pyx6707]
[Unloading class org.python.pycode._pyx6633]
but also a bunch of class unloading.

If the IBM VM have similar tools, you could try to investigate the problem.
With the old sun 1.2 -verbose:class did'nt show class unloading but -verbose:gc
did.

regards.

> On  a Windows 2000 system with 128M memory using IBM Java 1.3.0 (20010609)
> with the JIT on, java.exe's memory usage for this program steadily
> increases and performance decreases.  Eventually I get an OutOfMemory
> message.
>
> Elapsed time  Memory Usage  Time to complete 10,000 loops
> ------------  ------------  -----------------------------
>  1 minute      26,108 K      31 seconds
> 20 minutes    121,696 K      70 seconds
> 54 minutes    185,132 K     116 seconds
>
> A similar memory increase and performance degradation is true running this
> program on a Linux Redhat 7.1 system with 256M memory and using IBM Java
> 1.3.0 (20010626) with the JIT on.
>
> However, on a Windows ME system with 64M memory using Sun Java 1.3.1
> (HotSpot), there is no increase in memory usage and no performance
> degradation, even after this program has run for 24 hours.
>
> Here's the code for the SimpleEmbedded Java program that's running:
>
> import org.python.util.PythonInterpreter;
> import org.python.core.*;
>
> public class SimpleEmbedded {
>
>     public static void main(String []args) throws PyException {
>
>         PythonInterpreter interp = new PythonInterpreter();
>
>         interp.exec("import time");
>         interp.exec("LoopStartTime = time.time()");
>
>         int i = 1;
>         while (i > 0)
>         {
>             interp.eval("'This is a test'");
>
>             if (i % 10000 == 0)
>             {
>                 interp.exec("LoopStopTime = time.time()");
>                 interp.exec("LoopElapsedSecs = LoopStopTime -
> LoopStartTime");
>                 System.out.println("Completed Loop " + i +
>                     " - elapsed time: " + interp.get("LoopElapsedSecs") +
>                     " secs");
>                 interp.exec("LoopStartTime = time.time()");
>             }
>             i++;
>        }
>
>     }
> }

[Jython-users] Why Memory Usage Increase with a PythonInterpreter and running eval in a loop?

[Sharon L. <lu...@us...>]

Can anyone explain why the attached simple Java program which creates one
PythonInterpreter and then does an eval in a continuous loop using so much
memory on Windows 2000 and Linux?  Is it a Java problem or a Jython
problem?  Can it be fixed?

On  a Windows 2000 system with 128M memory using IBM Java 1.3.0 (20010609)
with the JIT on, java.exe's memory usage for this program steadily
increases and performance decreases.  Eventually I get an OutOfMemory
message.

Elapsed time  Memory Usage  Time to complete 10,000 loops
------------  ------------  -----------------------------
 1 minute      26,108 K      31 seconds
20 minutes    121,696 K      70 seconds
54 minutes    185,132 K     116 seconds

A similar memory increase and performance degradation is true running this
program on a Linux Redhat 7.1 system with 256M memory and using IBM Java
1.3.0 (20010626) with the JIT on.

However, on a Windows ME system with 64M memory using Sun Java 1.3.1
(HotSpot), there is no increase in memory usage and no performance
degradation, even after this program has run for 24 hours.

Here's the code for the SimpleEmbedded Java program that's running:

import org.python.util.PythonInterpreter;
import org.python.core.*;

public class SimpleEmbedded {

    public static void main(String []args) throws PyException {

        PythonInterpreter interp = new PythonInterpreter();

        interp.exec("import time");
        interp.exec("LoopStartTime = time.time()");

        int i = 1;
        while (i > 0)
        {
            interp.eval("'This is a test'");

            if (i % 10000 == 0)
            {
                interp.exec("LoopStopTime = time.time()");
                interp.exec("LoopElapsedSecs = LoopStopTime -
LoopStartTime");
                System.out.println("Completed Loop " + i +
                    " - elapsed time: " + interp.get("LoopElapsedSecs") +
                    " secs");
                interp.exec("LoopStartTime = time.time()");
            }
            i++;
       }

    }
}
--------------------------------------------------------------
Sharon Lucas
IBM Austin,   lu...@us...
(512) 838-8347 or Tieline 678-8347

Re: [Jython-users] Basic newbie questions: threads, spawning apps, SSL

[Frank C. <fc...@pu...>]

Thank you for the information. This worked great!

I need to create a Java object that does a URLConnection to an SSL web site.
I'll write up my notes and share it with the Jython-users list once I figure
out how to do it.

Thanks.

-Frank


-- 
Frank Cohen, founder, PushToTest, www.pushtotest.com, phone: 408 374 7426
Come to PushToTest for Load, a free open-source tool for performance and
scalability testing and data migration.

> From: Ype Kingma <yk...@xs...>
> Date: Fri, 21 Sep 2001 20:03:36 +0100
> To: jyt...@li...
> Subject: Re: [Jython-users] Basic newbie questions: threads, spawning apps,
> SSL
> 
> Frank,
> 
>> Some newbie questions. Thanks, in advance, for answering them.
>> 
>> 1) How do I find implemented methods and objects? For example, A Python book
> 
> You can use:
> dir(o)
> dir(o.__class__)
> 
>> shows how to use thread.start_new(count, (i, 3)) which generates this error:
>> AttributeError: class "org.python.modules.thread' has no attribute
>> 'start_new'. I'd like something - even the JavaDoc - that would help me find
>> and fix the problem.
> 
> It's called thread.start_new_thread()
> (http://www.python.org/doc/current/lib/module-thread.html)
> 
>> 2) Does Jython have an ability to handle "include" files? For eample, I have
>> one Jython script that calls a Jython script file and passes control to the
>> new script.
> 
> You can use execfile().
> (http://www.python.org/doc/current/lib/built-in-funcs.html)
> 
>> 3) Will someone point me in the right direction to do SSL in Jython.
> 
> That's more difficult: in jython you're limited to what java can
> offer you, and I don't recall having secure sockets in java.net.
> You might try to find any java implementation of secure sockets.
> 
> Good luck,
> Ype
> 
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users

[Jython-users] exec and globals

[Frank C. <fc...@pu...>]

If anyone will confirm this is the best way to use exec and globals, I would
certain appreciate your feedback.

The goal is to have the Jython equivalent of server-side include files where
one script calls another and can share variables. In an experiment I created
two files:

exec_example.py

def makethecall:
    i=100
    exec open("included.py").read()
    print "j=", j
makethecall()


included.py

j=101
print "i=", i

By running exec_example I see:

i=100
j=101

Is this the best way to have scripts calling other scripts and returning
results?

-Frank

-- 
Frank Cohen, founder, PushToTest, www.pushtotest.com, phone: 408 374 7426
Come to PushToTest for Load, a free open-source tool for performance and
scalability testing and data migration. 

Re: [Jython-users] embed a subset of Jython?

[Ype K. <yk...@xs...>]

John,

>I'd like to allow users of my app to be able to enter Jython code to
>control my app.  But I only want to support a subset of the language.
>
>Ideally I'd like to look at the description of the Jython language in
>the form of a hierarchy and pick and choose what to activate and what
>to suppress. For example, I'd like support for assignment statements
>but not the creation of classes.
>
>Does this sound like a reasonable goal?  Is anything like this possible
>w/o a lot of work?

You can use execfile() or exec in you program, and perform some simple
check on the actual program contents before allowing this.
Eg. to define a class in python the word 'class' must be at the
beginning of a line (after evt. whitespace). You can easily search
for that using regular expressions, and give the user some error message
when this happens.
Same for 'import'.
Beware of the standard functions: for example anything goes
when you allow __import__() or exec or execfile() in user code.

When the subset is easy enough you might define a simple parser for it
and use it as a check before executing the code by the full interpreter.

However, I don't like the idea of giving users anything less than the
full python language. Most of them can decide how much of the language
they would want to use.
Using your own parser as a filter at least allows an 'upgrade' to the
full language...

Have fun,
Ype

Re: [Jython-users] Basic newbie questions: threads, spawning apps, SSL

[Ted B. <te...@et...>]

On Friday 21 September 2001 12:03, Ype Kingma wrote:


> >3) Will someone point me in the right direction to do SSL in Jython.
>
> That's more difficult: in jython you're limited to what java can
> offer you, and I don't recall having secure sockets in java.net.
> You might try to find any java implementation of secure sockets.
>

As of 1.4 SSL is supported in java.  I haven't played with it myself, so 
that's all I can tell you.

JDK1.4 beta 2 is available from javasoft.com, but is not yet ready for public 
consumption.  Personally, I've had no trouble with it.


ted

[Jython-users] embed a subset of Jython?

[John M. <joh...@ya...>]

I'd like to allow users of my app to be able to enter Jython code to
control my app.  But I only want to support a subset of the language.

Ideally I'd like to look at the description of the Jython language in
the form of a hierarchy and pick and choose what to activate and what
to suppress. For example, I'd like support for assignment statements
but not the creation of classes.

Does this sound like a reasonable goal?  Is anything like this possible
w/o a lot of work?

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Re: [Jython-users] Multithreading in Jython

[John M. <joh...@ya...>]

Attached is an pair of example programs that compare the single
threading in CPython with the true multi-threading by using the Java
threads.  


 utah: /home/mudd/misc[1]  ls ?ThreadTestSerialize.py
cThreadTestSerialize.py  jThreadTestSerialize.py
 utah: /home/mudd/misc[1]  cThreadTestSerialize.py
self.id=1
self.id=2
self.id=0
Elapsed: 0.1126 sec
 utah: /home/mudd/misc[1]  jThreadTestSerialize.py
self.id=2
self.id=0
self.id=1
Elapsed: 0.2870 sec
 utah: /home/mudd/misc[1]  


--- R Datta <rd...@cr...> wrote:
> Hi all,
> 
> I am working on a program to simulate stress testing (large number of
> 
> users) on JDBC connections. I would like to multithread the JDBC
> operations.
> 
> I would appreciate some input (samples, tips etc) with anyone that
> has 
> tried multithreading within jython scripts.
> 
> Thanks
> Raj
> 
> Thanks
> Raj Datta
> Professional Services                           Direct   :
> 408-530-4932
> CrossAccess Corp                                Cell       :
> 408-316-5473
> 2900 Gordon Ave #100                       Fax       : 408-735-0328
> Santa Clara CA 95051                         Email   :
> rd...@cr...
> 
> 
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users


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Re: [Jython-users] Basic newbie questions: threads, spawning apps, SSL

[Ype K. <yk...@xs...>]

Frank,

>Some newbie questions. Thanks, in advance, for answering them.
>
>1) How do I find implemented methods and objects? For example, A Python book

You can use:
dir(o)
dir(o.__class__)

>shows how to use thread.start_new(count, (i, 3)) which generates this error:
>AttributeError: class "org.python.modules.thread' has no attribute
>'start_new'. I'd like something - even the JavaDoc - that would help me find
>and fix the problem.

It's called thread.start_new_thread()
(http://www.python.org/doc/current/lib/module-thread.html)

>2) Does Jython have an ability to handle "include" files? For eample, I have
>one Jython script that calls a Jython script file and passes control to the
>new script.

You can use execfile().
(http://www.python.org/doc/current/lib/built-in-funcs.html)

>3) Will someone point me in the right direction to do SSL in Jython.

That's more difficult: in jython you're limited to what java can
offer you, and I don't recall having secure sockets in java.net.
You might try to find any java implementation of secure sockets.

Good luck,
Ype

RE: [Jython-users] no popitem in jython 2.0

[Phil S. <psu...@es...>]

os to the os.chdir() thing, check out http://sourceforge.net/projects/jnios.
A few people have been talking about it recently on the list.
I tried it out, it works very well. It uses JNI so it
will not be an option in some cases. pipe() doesn't
work and it may not work under linux, though I'm hoping
a good linux person may solve that.

To use jnios, extract it and do something like this:

d:\projects>set path=d:\tools\jnios-1.7;%path%

d:\projects>set classpath=d:\tools\jnios-1.7\jnios.jar

d:\projects>jython -Dpython.path=d:\tools\jnios-1.7
Jython 2.1a3 on java1.3.0 (JIT: null)
Type "copyright", "credits" or "license" for more information.
>>> from jnios import os
>>> os.chdir(r'\temp')
>>> os.getcwd()
'd:\\temp'

Note that the jnios readme has instructions for making
jnios your default os package, obviating the need for
the from jnios import os statement.

As to popitem(): 2.1a3 supports it. But note that it
does not show up in the dir()?!

d:\projects>jython -Dpython.path=d:\tools\jnios-1.7
Jython 2.1a3 on java1.3.0 (JIT: null)
Type "copyright", "credits" or "license" for more information.
>>> a = {1:2, 3:4}
>>> dir(a)
['clear', 'copy', 'get', 'has_key', 'items', 'keys', 'setdefault', 'update',
'values']
>>> a.popitem()
(3, 4)
>>>
d:\projects>python
Python 2.1 (#15, Apr 16 2001, 18:25:49) [MSC 32 bit (Intel)] on win32
Type "copyright", "credits" or "license" for more information.
>>> a = {1:2, 3:4, 5:6}
>>> dir(a)
['clear', 'copy', 'get', 'has_key', 'items', 'keys', 'popitem',
'setdefault', 'update', values']
>>>

IMHO jython 2.1a3 is much better than Jython 2.0. Like you I stayed away
from it for a while because I prefer to avoid alpha software,
but it seems at least as stable as 2.0 to me and there are fewer
python/jython incompatibilities.

-----Original Message-----
From: Mark Robinson [mailto:blo...@ho...]
Sent: Friday, September 21, 2001 11:18 AM
To: jyt...@li...
Subject: [Jython-users] no popitem in jython 2.0


I am currently in the process of converting an application I wrote in
python to jython, so I can use swing for a GUI.

As far as GUI side goes so, excellent stuff, consider
my socks impressed off my feet.

However, there seem to be a number of python functionality,
that is missing in jython. Earlier today I realised I could
no longer use the os.chdir() method, and I have just noticed
that popitem() is not supported for dictionary objects (at
least in version 2.0, which was the latest stable release as
far as I can see)

Can anyone tell me if this is just a work in progress situation,
and these features are just waiting to added or if they haven't
been added for some particular reason.

Secondly, can anyone tell me if there are any other issues I may
have with code breakage moving from python2.1 to jython2.0?

Please don't get the wrong idea here, I think jython is wonderful
to use, and has saved me hours of work already ;), I am just trying
to evaluate just how much the differences are going to affect me.

cheers
Blobby


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[Jython-users] installation of v2.1a3

[Mark R. <blo...@ho...>]

Hey guys,

I have just downloaded version 2.1a3 (so I can use many of the
python 2.1 compatible features). The self extraction and installation
seeming to go fine with no errors, but when I type jython, it pauses
and then just returns to the command line.

can anyone help me get this working?

Blobby

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[Jython-users] no popitem in jython 2.0

[Mark R. <blo...@ho...>]

I am currently in the process of converting an application I wrote in
python to jython, so I can use swing for a GUI.

As far as GUI side goes so, excellent stuff, consider
my socks impressed off my feet.

However, there seem to be a number of python functionality,
that is missing in jython. Earlier today I realised I could
no longer use the os.chdir() method, and I have just noticed
that popitem() is not supported for dictionary objects (at
least in version 2.0, which was the latest stable release as
far as I can see)

Can anyone tell me if this is just a work in progress situation,
and these features are just waiting to added or if they haven't
been added for some particular reason.

Secondly, can anyone tell me if there are any other issues I may
have with code breakage moving from python2.1 to jython2.0?

Please don't get the wrong idea here, I think jython is wonderful
to use, and has saved me hours of work already ;), I am just trying
to evaluate just how much the differences are going to affect me.

cheers
Blobby


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[Jython-users] Is now GPL compatible?

[Carlos Q. <car...@rt...>]

HI

I'm just downloading Python 2.1.1 and notice that the license changed so
now it is GPL-compatible. Will this happen to jython as well?

Regards

Re: [Jython-users] no os.chdir() in jython?

[Sebastien P. <Seb...@is...>]

Mark Robinson wrote:

> Thanks!! I guess the java/jython way to do this is store the path
> and use the full path when writing files, rather than switching
> directories. It was probably bad practice anyhow ;), I exhibit lots
> of that.
> 
> It does seem strange that java doesn't have these capabilities,
> is it due to security do you know?

Well, I don't think it is a "security feature", because applets cannot
do what an application can do. As I've said you can set a property in
the JVM (something like "java.currentPath"), actually the Ant build tool
surely uses that when it runs a new program- maybe you could post on
their mailing list... but I'm curious to know why Sun hasen't put a
changeCurrentDir in the System class ;)

Cheers,
  -- Sebastien.

Re: [Jython-users] no os.chdir() in jython?

[Mark R. <blo...@ho...>]

>From: Sebastien Pierre <Seb...@is...>
>To: Mark Robinson <blo...@ho...>
>Subject: Re: [Jython-users] no os.chdir() in jython?
>Date: Fri, 21 Sep 2001 11:58:50 +0200
>
>
> > I have just found out that the os module in jython doesn't
> > include the os.chdir() method. Can anyone tell me how it's
> > functionality is usually achieved in jython?
>
>From what I know about Java, there is no way to change the current
>directory...Thought maybe using the JVM properties, but I don't remember
>the property name.

Thanks!! I guess the java/jython way to do this is store the path
and use the full path when writing files, rather than switching
directories. It was probably bad practice anyhow ;), I exhibit lots
of that.

It does seem strange that java doesn't have these capabilities,
is it due to security do you know?

cheers
blobby
>
>Cheers,
>
>  -- Sebastien.

_________________________________________________________________
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[Jython-users] no os.chdir() in jython?

[Mark R. <blo...@ho...>]

Hey guys,

I have just found out that the os module in jython doesn't
include the os.chdir() method. Can anyone tell me how it's
functionality is usually achieved in jython?

thanks

blobby

_________________________________________________________________
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[Jython-users] Basic newbie questions: threads, spawning apps, SSL

[Frank C. <fc...@pu...>]

Some newbie questions. Thanks, in advance, for answering them.

1) How do I find implemented methods and objects? For example, A Python book
shows how to use thread.start_new(count, (i, 3)) which generates this error:
AttributeError: class "org.python.modules.thread' has no attribute
'start_new'. I'd like something - even the JavaDoc - that would help me find
and fix the problem.

2) Does Jython have an ability to handle "include" files? For eample, I have
one Jython script that calls a Jython script file and passes control to the
new script.

3) Will someone point me in the right direction to do SSL in Jython.

Thanks.

-Frank

-- 
Frank Cohen, founder, PushToTest, www.pushtotest.com, phone: 408 374 7426
Come to PushToTest for Load, a free open-source tool for performance and
scalability testing and data migration. 

Re: [Jython-users] CLASSPATH problem

[Kevin M. <kev...@er...>]

Success!
I was being a little hasty when I tested and had a typo in the Class-Path.

I have so quickly gotten used to be being able to just do something in
Jython and having it work right away that this bug just threw me.

Thanks for your time and patience.

Best regards,
Kevin.


On Thu, 20 Sep 2001, Samuele Pedroni wrote:

> > Result:
> > -------
> > I have stopped adding the Class-Path field to the manifest, since Samuel
> > said that it ignores this and I can confirm it is so.
> >
> It's tricky. I said that Jython ignores  not Java.
> So the sys.add_package makes Jython aware of the package,
> but Jython uses Java to import the class
> so Java should know the jar,
> you need both the sys.add_package and the Class-Path in
> the manifest, if then it's still not working
> is just a matter of getting Class-Path right ;)
>
> regards, Samuele Pedroni.
>

_________________________________________________
Name/Title : Kevin McNamee, Software Consultant
Phone      : +46 13 32 1165

Re: [Jython-users] Multithreading in Jython

[Kevin B. <kb...@ca...>]

Here's a little sample code.
---
from threading import Thread
from time import time

class Job( Thread ):
    def run( self ):
        v = 0L
        for i in xrange( 1, 200000 ):
            v = v + i
        self.value = v

def _test( n=1 ):
    jobs = []
    for i in range( n ):
        jobs.append( Job() )

    start = time()
    map( Job.start, jobs )
    map( Job.join, jobs )
    t = time() - start

    print "%d: %.3f/%.3f" % (n, t, n and t/n)
        
map( _test, range( 5 ))

---

Note that the example above doesn't get a speedup from multiple threads, even on a two CPU box. 
Of course, if your threads are blocking on a JDBC call, you'll see a speedup...  :-)

<ObDisc>
These are microbenchmarks are thus not worth the electrons it takes to view them.
</ObDisc>

Although Jython doesn't appear to have a "global interpreter lock" a la CPython, my 2-CPU NT box shows 1 CPU utilized for 1 thread, both CPUs fully utilized for two or more threads, but the times look like:

0: 0.000/0.000
1: 0.719/0.719
2: 1.656/0.828
3: 2.485/0.828
4: 3.329/0.832

So, more threads use more CPU, but are slightly slower, even on a two-CPU box.

If you just run the 'run' method of all the jobs, instead of starting a new thread for each of them, you get better times:

0: 0.000/0.000
1: 0.656/0.656
2: 1.297/0.648
3: 1.953/0.651
4: 2.594/0.648

FWIW, the numbers for CPython are much worse (thank that global interpreter lock):

0: 0.000/0.000
1: 0.703/0.703
2: 5.360/2.680
3: 10.969/3.656
4: 11.656/2.914

CPython only uses one CPU, but still incurs the overhead of thread switching - not a pretty picture.

These results were obtained on:

Jython 2.1a1 on java1.3.0 (JIT: null)
Sun JDK 1.3.0
WinNT 4.0 SP 6a
2x PIII 600

kb


R Datta wrote:
> 
> Hi all,
> 
> I am working on a program to simulate stress testing (large number of
> users) on JDBC connections. I would like to multithread the JDBC operations.
> 
> I would appreciate some input (samples, tips etc) with anyone that has
> tried multithreading within jython scripts.
> 
> Thanks
> Raj
> 
> Thanks
> Raj Datta
> Professional Services                           Direct   : 408-530-4932
> CrossAccess Corp                                Cell       : 408-316-5473
> 2900 Gordon Ave #100                       Fax       : 408-735-0328
> Santa Clara CA 95051                         Email   : rd...@cr...
> 
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users

[Jython-users] Multithreading in Jython

[R D. <rd...@cr...>]

Hi all,

I am working on a program to simulate stress testing (large number of 
users) on JDBC connections. I would like to multithread the JDBC operations.

I would appreciate some input (samples, tips etc) with anyone that has 
tried multithreading within jython scripts.

Thanks
Raj

Thanks
Raj Datta
Professional Services                           Direct   : 408-530-4932
CrossAccess Corp                                Cell       : 408-316-5473
2900 Gordon Ave #100                       Fax       : 408-735-0328
Santa Clara CA 95051                         Email   : rd...@cr...

Re: [Jython-users] CLASSPATH problem

[Samuele P. <pe...@in...>]

> Result:
> -------
> I have stopped adding the Class-Path field to the manifest, since Samuel
> said that it ignores this and I can confirm it is so.
> 
It's tricky. I said that Jython ignores  not Java.
So the sys.add_package makes Jython aware of the package,
but Jython uses Java to import the class
so Java should know the jar,
you need both the sys.add_package and the Class-Path in
the manifest, if then it's still not working
is just a matter of getting Class-Path right ;)

regards, Samuele Pedroni.

Re: [Jython-users] [ANN] JythonInterpreter 0.5 and PyUtils 0.1

[Noel R. <no...@ya...>]

>
>F5 - Import the current buffer into the interpreter (or reload)
>
>And Run buffer (with and without step debugging)

Attached is a JEdit macro that will run Jython on the current buffer and 
place the output in the JEdit console.  It's only a couple of lines long, 
so should be easily adaptable to your own environment.  Place it in the 
jEdit/macros/Console_Plugin directory, and restart JEdit.  Once it's there, 
it'll show up in the Macros >> Console Plugin menu, and you can assign a 
key shortcut to it.  It doesn't integrate with the JythonInterpreter 
plugin, but it's still pretty nice to have.

Noel