jython-users — Discussion of and questions about using Jython

Re: [Jython-users] PySerial & RXTX query

[Adam B. <ada...@gm...>]

Hi, do you get exceptions, or can you share a simple test program?

Adam

> 在 24 Sep 2016，4:15 PM，Corgi <co...@te...> 写道：
> 
> I have had no success with opening a serial port (device is a Prolific USB
> to serial comm port [COM9]) from Jython (2.7) using PySerial (tried both 2.7
> and 3.1.1) and the RXTX replacement for javax.comm on windows 64 bit.  I
> have tried the usual googling for examples but found no really helpful
> jython specific ones.  If anyone has an example program that works, I should
> be really grateful to see it!
> 
> It all works fine in Python 2.7 !
> 
> Thanks in advance,
> 
> Graham
> 
> (Apologies if this is posted twice) 
> 
> 
> ------------------------------------------------------------------------------
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users

[Jython-users] PySerial & RXTX query

[Corgi <co...@te...>]

I have had no success with opening a serial port (device is a Prolific USB
to serial comm port [COM9]) from Jython (2.7) using PySerial (tried both 2.7
and 3.1.1) and the RXTX replacement for javax.comm on windows 64 bit.  I
have tried the usual googling for examples but found no really helpful
jython specific ones.  If anyone has an example program that works, I should
be really grateful to see it!

It all works fine in Python 2.7 !

Thanks in advance,

Graham

(Apologies if this is posted twice) 

[Jython-users] Jython class factory?

[David C. <dav...@gm...>]

I am currently using the object-factory technique: I instantiate a Jython
object that implements a Java interface and then call __tojava__() and use
the retuned object in my Java code.

However, the only thing I do with the object returned from __tojava__() in
this case is call getClass(). So, the instantiation step seems
wasteful/awkward/misleading. I wonder, is it possible to skip the
instantiation step and return a Java *class* rather than a Java *object*?

I tried some things, but this area of Jython is pure magic to me.

Thanks,
David

[Jython-users] Robot / Jython / centos (AWS) slowness

[Adam B. <ada...@gm...>]

I haven't used the AWS centos setup, so was delaying to see if anyone had. A few general comments ...

With robot framework, the performance limits we have found are usually memory intensiveness causing gc. Our setup is quite hungry for PermGen before 1.8 (we recently upgraded). There's quite a few temporary objects created as well. Given we are talking about multiple layers of interpreted languages I don't think that's unreasonable from a design perspective but it is worth being aware of. We also have internal data structures like message queues created for each test case for our own reasons (we have a message driven app). This exacerbates it.

We have found that if multiple layers of BDD functions are used (keywords or directives in robot-lingo), this is again more intense. Refactoring the inner functions into Python or Java shows improvements pretty quickly. Not that surprising perhaps but just a data point for others in this setup. 

On a tangent, Michael Feathers had an interesting post about "starting dynamic and ending statically" recently that is very similar to this refactoring / optimization.

https://michaelfeathers.silvrback.com/the-ergonomics-of-type-checking

I think he is actually suggesting future language / tooling design could support this sort of workflow to be a routine daily thing instead of a refactoring done over weeks or months. Would be curious if anyone in this crowd has thought about that too.

Cheers
Adam

> 在 19 Sep 2016，2:45 PM，Matt Rutherford <mjr...@gm...> 写道：
> 
> I also implemented this stack for my work's automated test runs, but with python robot. I have noticed though the robot python packages running exceptionally slow on (aws) centos. I wanted to know if others ever encountered such an issue?
> 
> 
>> On 19 Sep 2016 12:48 a.m., "Adam Burke" <ada...@gm...> wrote:
>> We use it this way, but in different apps. A django web app which is CPython and BDD testing for Java applications using Robot + Jython.
>> 
>> Adam
>> 
>>> 在 17 Sep 2016，3:03 PM，Matt Rutherford <mjr...@gm...> 写道：
>>> 
>>> I'd be interested in hearing the various use cases people have for python that made them opt for 'both' as opposed to purely python or Java?
>>> 
>>> 
>>>> On 17 Sep 2016 2:42 a.m., "Jon Christopher" <jon...@gm...> wrote:
>>>> I love jython and use it frequently, and have over 3 decades of programming experience----so not quite a newbie.
>>>> 
>>>> Jython works like magic for the most part but the integration is so slick sometimes I forget which platform I'm on.  The Java objects start looking like python objects and vice versa (which is the whole point, after all), but it can be a bit confusing---even though it all just works.
>>>> 
>>>> So...I'm willing to cut the newbies some slack on their confusion here.
>>>> 
>>>> -Jon
>>>> 
>>>> 
>>>>> On Fri, Sep 16, 2016 at 6:29 PM, Adam Burke <ada...@gm...> wrote:
>>>>> It doesn't, of course - it looks like a  reaction from a beginner who hasn't learnt to contextually separate a language from the platform surrounding it.
>>>>> 
>>>>> It might speak to the need for clearer doco entry points, though. The dominance (and usefulness) of stackoverflow for new programmers is also interesting. Because the foundation of jython predates it, there's not as much of a community around Jython there, that I've seen.
>>>>> 
>>>>> We made the wiki closed to anon edits because of nasty spam problems, but contributors are very welcome - just ask on this mailing list.
>>>>> 
>>>>> Adam
>>>>> 
>>>>> > 在 17 Sep 2016，8:32 AM，Michael Chisholm <chi...@mi...> 写道：
>>>>> >
>>>>> > On 9/16/2016 1:13 PM, Guzdial, Mark wrote:
>>>>> >>> Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead?
>>>>> >>
>>>>> >>
>>>>> >> Actually, many of the students at University who are learning Python are actually learning Jython.  The textbook that Barbara Ericson and I wrote uses Jython: https://www.amazon.com/Introduction-Computing-Programming-Python-4th/dp/0134025547.  Last I saw market analysis, it's the third most popular Python University textbook, at least in the US.  If you read the reviews for the book, you'll see that lots of people are confused about Jython vs. Python.  Quoting one:
>>>>> >>
>>>>> >>
>>>>> >> This book is a prescribed text for a course: that's the only reason to buy it. Its biggest problem: false advertising. This is NOT a book on Python, it's about JYTHON - A Java based imitation of Python.
>>>>> >> Why? Well, there's some pretty software, available to download, which uses the the JRE. The author chose to stick with this "easy learning environment" and basically cripple anyone wanting to write Python code for Blender, Maya, Android etc.
>>>>> >>
>>>>> >> You may learn to program from this text, but don't expect a trouble-free life when you get exposed to the real language.
>>>>> >>
>>>>> >>
>>>>> >> The IDE that we wrote for the book, JES, is all Jython, and has been used by thousands of students for over a decade now: See http://cacm.acm.org/blogs/blog-cacm/205801-14-years-of-a-learner-centered-python-ide/fulltext
>>>>> >
>>>>> > So I'll just ask the obvious: CPython and Jython are supposed to be
>>>>> > alternative implementations of the same language, Python.  IronPython is
>>>>> > another.  How does a different implementation imply a different language?
>>>>> >
>>>>> > Andy
>>>>> >
>>>>> >
>>>>> >
>>>>> > ------------------------------------------------------------------------------
>>>>> > _______________________________________________
>>>>> > Jython-users mailing list
>>>>> > Jyt...@li...
>>>>> > https://lists.sourceforge.net/lists/listinfo/jython-users
>>>>> 
>>>>> ------------------------------------------------------------------------------
>>>>> _______________________________________________
>>>>> Jython-users mailing list
>>>>> Jyt...@li...
>>>>> https://lists.sourceforge.net/lists/listinfo/jython-users
>>>> 
>>>> 
>>>> ------------------------------------------------------------------------------
>>>> 
>>>> _______________________________________________
>>>> Jython-users mailing list
>>>> Jyt...@li...
>>>> https://lists.sourceforge.net/lists/listinfo/jython-users
>>> ------------------------------------------------------------------------------
>>> _______________________________________________
>>> Jython-users mailing list
>>> Jyt...@li...
>>> https://lists.sourceforge.net/lists/listinfo/jython-users

[Jython-users] Play

[Sayth R. <fle...@gm...>]

Can i use Jython to work with the play framework?

Rather than Scala for Play and Spark just wondering if that is a jython
opportunity.


Thanks

Sayth

Re: [Jython-users] the health of Jython

[Matt R. <mjr...@gm...>]

I also implemented this stack for my work's automated test runs, but with
python robot. I have noticed though the robot python packages running
exceptionally slow on (aws) centos. I wanted to know if others ever
encountered such an issue?

On 19 Sep 2016 12:48 a.m., "Adam Burke" <ada...@gm...> wrote:

> We use it this way, but in different apps. A django web app which is
> CPython and BDD testing for Java applications using Robot + Jython.
>
> Adam
>
> 在 17 Sep 2016，3:03 PM，Matt Rutherford <mjr...@gm...> 写道：
>
> I'd be interested in hearing the various use cases people have for python
> that made them opt for 'both' as opposed to purely python or Java?
>
> On 17 Sep 2016 2:42 a.m., "Jon Christopher" <jon...@gm...>
> wrote:
>
>> I love jython and use it frequently, and have over 3 decades of
>> programming experience----so not quite a newbie.
>>
>> Jython works like magic for the most part but the integration is so slick
>> sometimes I forget which platform I'm on.  The Java objects start looking
>> like python objects and vice versa (which is the whole point, after all),
>> but it can be a bit confusing---even though it all just works.
>>
>> So...I'm willing to cut the newbies some slack on their confusion here.
>>
>> -Jon
>>
>>
>> On Fri, Sep 16, 2016 at 6:29 PM, Adam Burke <ada...@gm...>
>> wrote:
>>
>>> It doesn't, of course - it looks like a  reaction from a beginner who
>>> hasn't learnt to contextually separate a language from the platform
>>> surrounding it.
>>>
>>> It might speak to the need for clearer doco entry points, though. The
>>> dominance (and usefulness) of stackoverflow for new programmers is also
>>> interesting. Because the foundation of jython predates it, there's not as
>>> much of a community around Jython there, that I've seen.
>>>
>>> We made the wiki closed to anon edits because of nasty spam problems,
>>> but contributors are very welcome - just ask on this mailing list.
>>>
>>> Adam
>>>
>>> > 在 17 Sep 2016，8:32 AM，Michael Chisholm <chi...@mi...> 写道：
>>> >
>>> > On 9/16/2016 1:13 PM, Guzdial, Mark wrote:
>>> >>> Apparently a lot of new programmers are being introduced to
>>> programming through CPython ... shouldn't the poor kids be learning Jython
>>> instead?
>>> >>
>>> >>
>>> >> Actually, many of the students at University who are learning Python
>>> are actually learning Jython.  The textbook that Barbara Ericson and I
>>> wrote uses Jython: https://www.amazon.com/Introdu
>>> ction-Computing-Programming-Python-4th/dp/0134025547.  Last I saw
>>> market analysis, it's the third most popular Python University textbook, at
>>> least in the US.  If you read the reviews for the book, you'll see that
>>> lots of people are confused about Jython vs. Python.  Quoting one:
>>> >>
>>> >>
>>> >> This book is a prescribed text for a course: that's the only reason
>>> to buy it. Its biggest problem: false advertising. This is NOT a book on
>>> Python, it's about JYTHON - A Java based imitation of Python.
>>> >> Why? Well, there's some pretty software, available to download, which
>>> uses the the JRE. The author chose to stick with this "easy learning
>>> environment" and basically cripple anyone wanting to write Python code for
>>> Blender, Maya, Android etc.
>>> >>
>>> >> You may learn to program from this text, but don't expect a
>>> trouble-free life when you get exposed to the real language.
>>> >>
>>> >>
>>> >> The IDE that we wrote for the book, JES, is all Jython, and has been
>>> used by thousands of students for over a decade now: See
>>> http://cacm.acm.org/blogs/blog-cacm/205801-14-years-of-a-lea
>>> rner-centered-python-ide/fulltext
>>> >
>>> > So I'll just ask the obvious: CPython and Jython are supposed to be
>>> > alternative implementations of the same language, Python.  IronPython
>>> is
>>> > another.  How does a different implementation imply a different
>>> language?
>>> >
>>> > Andy
>>> >
>>> >
>>> >
>>> > ------------------------------------------------------------
>>> ------------------
>>> > _______________________________________________
>>> > Jython-users mailing list
>>> > Jyt...@li...
>>> > https://lists.sourceforge.net/lists/listinfo/jython-users
>>>
>>> ------------------------------------------------------------
>>> ------------------
>>> _______________________________________________
>>> Jython-users mailing list
>>> Jyt...@li...
>>> https://lists.sourceforge.net/lists/listinfo/jython-users
>>>
>>
>>
>> ------------------------------------------------------------
>> ------------------
>>
>> _______________________________________________
>> Jython-users mailing list
>> Jyt...@li...
>> https://lists.sourceforge.net/lists/listinfo/jython-users
>>
>> ------------------------------------------------------------
> ------------------
>
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users
>
>

Re: [Jython-users] the health of Jython

[Adam B. <ada...@gm...>]

: )

Sure, I guess that's true, I have fallen into this uncanny valley as well. I have also been pleasantly surprised when something I didn't expect to work (eg network library support) just did, because the underlying work of reimplementing using the Java standard libraries.

Adam

> 在 17 Sep 2016，9:40 AM，Jon Christopher <jon...@gm...> 写道：
> 
> I love jython and use it frequently, and have over 3 decades of programming experience----so not quite a newbie.
> 
> Jython works like magic for the most part but the integration is so slick sometimes I forget which platform I'm on.  The Java objects start looking like python objects and vice versa (which is the whole point, after all), but it can be a bit confusing---even though it all just works.
> 
> So...I'm willing to cut the newbies some slack on their confusion here.
> 
> -Jon
> 
> 
>> On Fri, Sep 16, 2016 at 6:29 PM, Adam Burke <ada...@gm...> wrote:
>> It doesn't, of course - it looks like a  reaction from a beginner who hasn't learnt to contextually separate a language from the platform surrounding it.
>> 
>> It might speak to the need for clearer doco entry points, though. The dominance (and usefulness) of stackoverflow for new programmers is also interesting. Because the foundation of jython predates it, there's not as much of a community around Jython there, that I've seen.
>> 
>> We made the wiki closed to anon edits because of nasty spam problems, but contributors are very welcome - just ask on this mailing list.
>> 
>> Adam
>> 
>> > 在 17 Sep 2016，8:32 AM，Michael Chisholm <chi...@mi...> 写道：
>> >
>> > On 9/16/2016 1:13 PM, Guzdial, Mark wrote:
>> >>> Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead?
>> >>
>> >>
>> >> Actually, many of the students at University who are learning Python are actually learning Jython.  The textbook that Barbara Ericson and I wrote uses Jython: https://www.amazon.com/Introduction-Computing-Programming-Python-4th/dp/0134025547.  Last I saw market analysis, it's the third most popular Python University textbook, at least in the US.  If you read the reviews for the book, you'll see that lots of people are confused about Jython vs. Python.  Quoting one:
>> >>
>> >>
>> >> This book is a prescribed text for a course: that's the only reason to buy it. Its biggest problem: false advertising. This is NOT a book on Python, it's about JYTHON - A Java based imitation of Python.
>> >> Why? Well, there's some pretty software, available to download, which uses the the JRE. The author chose to stick with this "easy learning environment" and basically cripple anyone wanting to write Python code for Blender, Maya, Android etc.
>> >>
>> >> You may learn to program from this text, but don't expect a trouble-free life when you get exposed to the real language.
>> >>
>> >>
>> >> The IDE that we wrote for the book, JES, is all Jython, and has been used by thousands of students for over a decade now: See http://cacm.acm.org/blogs/blog-cacm/205801-14-years-of-a-learner-centered-python-ide/fulltext
>> >
>> > So I'll just ask the obvious: CPython and Jython are supposed to be
>> > alternative implementations of the same language, Python.  IronPython is
>> > another.  How does a different implementation imply a different language?
>> >
>> > Andy
>> >
>> >
>> >
>> > ------------------------------------------------------------------------------
>> > _______________________________________________
>> > Jython-users mailing list
>> > Jyt...@li...
>> > https://lists.sourceforge.net/lists/listinfo/jython-users
>> 
>> ------------------------------------------------------------------------------
>> _______________________________________________
>> Jython-users mailing list
>> Jyt...@li...
>> https://lists.sourceforge.net/lists/listinfo/jython-users
> 
> ------------------------------------------------------------------------------
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users

Re: [Jython-users] the health of Jython

[Adam B. <ada...@gm...>]

We use it this way, but in different apps. A django web app which is CPython and BDD testing for Java applications using Robot + Jython.

Adam

> 在 17 Sep 2016，3:03 PM，Matt Rutherford <mjr...@gm...> 写道：
> 
> I'd be interested in hearing the various use cases people have for python that made them opt for 'both' as opposed to purely python or Java?
> 
> 
>> On 17 Sep 2016 2:42 a.m., "Jon Christopher" <jon...@gm...> wrote:
>> I love jython and use it frequently, and have over 3 decades of programming experience----so not quite a newbie.
>> 
>> Jython works like magic for the most part but the integration is so slick sometimes I forget which platform I'm on.  The Java objects start looking like python objects and vice versa (which is the whole point, after all), but it can be a bit confusing---even though it all just works.
>> 
>> So...I'm willing to cut the newbies some slack on their confusion here.
>> 
>> -Jon
>> 
>> 
>>> On Fri, Sep 16, 2016 at 6:29 PM, Adam Burke <ada...@gm...> wrote:
>>> It doesn't, of course - it looks like a  reaction from a beginner who hasn't learnt to contextually separate a language from the platform surrounding it.
>>> 
>>> It might speak to the need for clearer doco entry points, though. The dominance (and usefulness) of stackoverflow for new programmers is also interesting. Because the foundation of jython predates it, there's not as much of a community around Jython there, that I've seen.
>>> 
>>> We made the wiki closed to anon edits because of nasty spam problems, but contributors are very welcome - just ask on this mailing list.
>>> 
>>> Adam
>>> 
>>> > 在 17 Sep 2016，8:32 AM，Michael Chisholm <chi...@mi...> 写道：
>>> >
>>> > On 9/16/2016 1:13 PM, Guzdial, Mark wrote:
>>> >>> Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead?
>>> >>
>>> >>
>>> >> Actually, many of the students at University who are learning Python are actually learning Jython.  The textbook that Barbara Ericson and I wrote uses Jython: https://www.amazon.com/Introduction-Computing-Programming-Python-4th/dp/0134025547.  Last I saw market analysis, it's the third most popular Python University textbook, at least in the US.  If you read the reviews for the book, you'll see that lots of people are confused about Jython vs. Python.  Quoting one:
>>> >>
>>> >>
>>> >> This book is a prescribed text for a course: that's the only reason to buy it. Its biggest problem: false advertising. This is NOT a book on Python, it's about JYTHON - A Java based imitation of Python.
>>> >> Why? Well, there's some pretty software, available to download, which uses the the JRE. The author chose to stick with this "easy learning environment" and basically cripple anyone wanting to write Python code for Blender, Maya, Android etc.
>>> >>
>>> >> You may learn to program from this text, but don't expect a trouble-free life when you get exposed to the real language.
>>> >>
>>> >>
>>> >> The IDE that we wrote for the book, JES, is all Jython, and has been used by thousands of students for over a decade now: See http://cacm.acm.org/blogs/blog-cacm/205801-14-years-of-a-learner-centered-python-ide/fulltext
>>> >
>>> > So I'll just ask the obvious: CPython and Jython are supposed to be
>>> > alternative implementations of the same language, Python.  IronPython is
>>> > another.  How does a different implementation imply a different language?
>>> >
>>> > Andy
>>> >
>>> >
>>> >
>>> > ------------------------------------------------------------------------------
>>> > _______________________________________________
>>> > Jython-users mailing list
>>> > Jyt...@li...
>>> > https://lists.sourceforge.net/lists/listinfo/jython-users
>>> 
>>> ------------------------------------------------------------------------------
>>> _______________________________________________
>>> Jython-users mailing list
>>> Jyt...@li...
>>> https://lists.sourceforge.net/lists/listinfo/jython-users
>> 
>> 
>> ------------------------------------------------------------------------------
>> 
>> _______________________________________________
>> Jython-users mailing list
>> Jyt...@li...
>> https://lists.sourceforge.net/lists/listinfo/jython-users
> ------------------------------------------------------------------------------
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users

Re: [Jython-users] the health of Jython

[Mike R. <mro...@ya...>]

(hopefully this a reply to Mark G in thread?)
... interesting.  Yes, I can see how one might feel short-changed if a CPython devotee and a Java-hater.
The slow startup time for Jython runs (to which I alluded in my second post a couple of days ago) will no doubt be giving generations of such students a bad image of Jython.  As a Jython author have you ever tried to tackle this aspect (e.g. by Nailgun)?
Mike

      From: "Guzdial, Mark" <gu...@cc...>
 To: Stefan Richthofer <Ste...@gm...>; "mro...@ya..." <mro...@ya...> 
Cc: "jyt...@li..." <jyt...@li...>
 Sent: Friday, 16 September 2016, 18:13
 Subject: Re: [Jython-users] the health of Jython
   
 <!--#yiv1337962315 P {margin-top:0;margin-bottom:0;}-->> Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead?

Actually, many of the students at University who are learning Python are actually learning Jython.  The textbook that Barbara Ericson and I wrote uses Jython: https://www.amazon.com/Introduction-Computing-Programming-Python-4th/dp/0134025547.  Last I saw market analysis, it's the third most popular Python University textbook, at least in the US.  If you read the reviews for the book, you'll see that lots of people are confused about Jython vs. Python.  Quoting one:
This book is a prescribed text for a course: that's the only reason to buy it. Its biggest problem: false advertising. This is NOT a book on Python, it's about JYTHON - A Java based imitation of Python.Why? Well, there's some pretty software, available to download, which uses the the JRE. The author chose to stick with this "easy learning environment" and basically cripple anyone wanting to write Python code for Blender, Maya, Android etc.
You may learn to program from this text, but don't expect a trouble-free life when you get exposed to the real language.
The IDE that we wrote for the book, JES, is all Jython, and has been used by thousands of students for over a decade now: See http://cacm.acm.org/blogs/blog-cacm/205801-14-years-of-a-learner-centered-python-ide/fulltext
- MarkFrom: Stefan Richthofer <Ste...@gm...>
Sent: Friday, September 16, 2016 9:53:28 AM
To: mro...@ya...
Cc: jyt...@li...
Subject: Re: [Jython-users] the health of Jython Hello Mike, completely agree with you in most points. Mainly I'd like to hint to the  https://wiki.python.org/jython/IrcChannel as an alternative for posting questions.While not very active, it is at least rather responsive (usually within some hours or so).I think a keypoint would be to bring the homepage and Wiki up to date. E.g. I once experienced it hard to find setup instructions to get pip etc running, install modules for Jython, including clarification how or how not this interfers with a CPython installation or modules installed via a package manager in Linux. Often enough such stuff is only implicitly documented via stackoverflow or so. There are rumors a new homepage is upcoming via github pages, but I don't know about an official statement.Also the delay of Jython 2.7.1 isn't exactly beneficious for the issues you mention I guess.It appears all in all this boils down to a lack of manpower for maintaining Jython. But I agree that maybe organization structures could actually be more friendly for contributing to the wiki or homepage and other documentation. We should definitely think this over! > Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead?A good starting point on this front would be an up-to-date getting-started-tutorial for Jython, including Java integration-hints. Maybe such a thing already exists somewhere (hints?), but I usually found such information rather spread over various places. Jython-book is usually the best source of information, but is also outdated and not exactly a tutorial. We would need something that covers Jython 2.7. So much for now. Have a nice weekend! -Stefan Gesendet: Donnerstag, 15. September 2016 um 20:48 Uhr
Von: "Mike Rodent" <mro...@ya...>
An: "jyt...@li..." <jyt...@li...>
Betreff: [Jython-users] the health of JythonI love Jython ... and I think you people who develop it are geniuses. But just looking at the archives for this mailing list tells its own story.  In the early years you see hundreds of posts a month sometimes... in the whole of March this year there was precisely ONE post. As I understand it, Jython was quite actively developed in its early years, and then went a bit quiet, but is now getting developed quite actively (no doubt Jython 3 will provoke some more interest).  And yet there is nothing but this mailing list to pose questions, etc. Does no-one here think that a mailing list as the centre of the Jython community is slightly anachronistic in 2016?  Wouldn't a simple forum tend to encourage new users to sniff out the power of the language? The goodness of Jython should be evangelised!  Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead? Just a thought!Mike ------------------------------------------------------------------------------ _______________________________________________ Jython-users mailing list Jyt...@li...https://lists.sourceforge.net/lists/listinfo/jython-users

   

Re: [Jython-users] the health of Jython

[Matt R. <mjr...@gm...>]

I'd be interested in hearing the various use cases people have for python
that made them opt for 'both' as opposed to purely python or Java?

On 17 Sep 2016 2:42 a.m., "Jon Christopher" <jon...@gm...>
wrote:

> I love jython and use it frequently, and have over 3 decades of
> programming experience----so not quite a newbie.
>
> Jython works like magic for the most part but the integration is so slick
> sometimes I forget which platform I'm on.  The Java objects start looking
> like python objects and vice versa (which is the whole point, after all),
> but it can be a bit confusing---even though it all just works.
>
> So...I'm willing to cut the newbies some slack on their confusion here.
>
> -Jon
>
>
> On Fri, Sep 16, 2016 at 6:29 PM, Adam Burke <ada...@gm...>
> wrote:
>
>> It doesn't, of course - it looks like a  reaction from a beginner who
>> hasn't learnt to contextually separate a language from the platform
>> surrounding it.
>>
>> It might speak to the need for clearer doco entry points, though. The
>> dominance (and usefulness) of stackoverflow for new programmers is also
>> interesting. Because the foundation of jython predates it, there's not as
>> much of a community around Jython there, that I've seen.
>>
>> We made the wiki closed to anon edits because of nasty spam problems, but
>> contributors are very welcome - just ask on this mailing list.
>>
>> Adam
>>
>> > 在 17 Sep 2016，8:32 AM，Michael Chisholm <chi...@mi...> 写道：
>> >
>> > On 9/16/2016 1:13 PM, Guzdial, Mark wrote:
>> >>> Apparently a lot of new programmers are being introduced to
>> programming through CPython ... shouldn't the poor kids be learning Jython
>> instead?
>> >>
>> >>
>> >> Actually, many of the students at University who are learning Python
>> are actually learning Jython.  The textbook that Barbara Ericson and I
>> wrote uses Jython: https://www.amazon.com/Introdu
>> ction-Computing-Programming-Python-4th/dp/0134025547.  Last I saw market
>> analysis, it's the third most popular Python University textbook, at least
>> in the US.  If you read the reviews for the book, you'll see that lots of
>> people are confused about Jython vs. Python.  Quoting one:
>> >>
>> >>
>> >> This book is a prescribed text for a course: that's the only reason to
>> buy it. Its biggest problem: false advertising. This is NOT a book on
>> Python, it's about JYTHON - A Java based imitation of Python.
>> >> Why? Well, there's some pretty software, available to download, which
>> uses the the JRE. The author chose to stick with this "easy learning
>> environment" and basically cripple anyone wanting to write Python code for
>> Blender, Maya, Android etc.
>> >>
>> >> You may learn to program from this text, but don't expect a
>> trouble-free life when you get exposed to the real language.
>> >>
>> >>
>> >> The IDE that we wrote for the book, JES, is all Jython, and has been
>> used by thousands of students for over a decade now: See
>> http://cacm.acm.org/blogs/blog-cacm/205801-14-years-of-a-
>> learner-centered-python-ide/fulltext
>> >
>> > So I'll just ask the obvious: CPython and Jython are supposed to be
>> > alternative implementations of the same language, Python.  IronPython is
>> > another.  How does a different implementation imply a different
>> language?
>> >
>> > Andy
>> >
>> >
>> >
>> > ------------------------------------------------------------
>> ------------------
>> > _______________________________________________
>> > Jython-users mailing list
>> > Jyt...@li...
>> > https://lists.sourceforge.net/lists/listinfo/jython-users
>>
>> ------------------------------------------------------------
>> ------------------
>> _______________________________________________
>> Jython-users mailing list
>> Jyt...@li...
>> https://lists.sourceforge.net/lists/listinfo/jython-users
>>
>
>
> ------------------------------------------------------------
> ------------------
>
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users
>
>

Re: [Jython-users] the health of Jython

[Jon C. <jon...@gm...>]

I love jython and use it frequently, and have over 3 decades of programming
experience----so not quite a newbie.

Jython works like magic for the most part but the integration is so slick
sometimes I forget which platform I'm on.  The Java objects start looking
like python objects and vice versa (which is the whole point, after all),
but it can be a bit confusing---even though it all just works.

So...I'm willing to cut the newbies some slack on their confusion here.

-Jon


On Fri, Sep 16, 2016 at 6:29 PM, Adam Burke <ada...@gm...> wrote:

> It doesn't, of course - it looks like a  reaction from a beginner who
> hasn't learnt to contextually separate a language from the platform
> surrounding it.
>
> It might speak to the need for clearer doco entry points, though. The
> dominance (and usefulness) of stackoverflow for new programmers is also
> interesting. Because the foundation of jython predates it, there's not as
> much of a community around Jython there, that I've seen.
>
> We made the wiki closed to anon edits because of nasty spam problems, but
> contributors are very welcome - just ask on this mailing list.
>
> Adam
>
> > 在 17 Sep 2016，8:32 AM，Michael Chisholm <chi...@mi...> 写道：
> >
> > On 9/16/2016 1:13 PM, Guzdial, Mark wrote:
> >>> Apparently a lot of new programmers are being introduced to
> programming through CPython ... shouldn't the poor kids be learning Jython
> instead?
> >>
> >>
> >> Actually, many of the students at University who are learning Python
> are actually learning Jython.  The textbook that Barbara Ericson and I
> wrote uses Jython: https://www.amazon.com/Introduction-Computing-
> Programming-Python-4th/dp/0134025547.  Last I saw market analysis, it's
> the third most popular Python University textbook, at least in the US.  If
> you read the reviews for the book, you'll see that lots of people are
> confused about Jython vs. Python.  Quoting one:
> >>
> >>
> >> This book is a prescribed text for a course: that's the only reason to
> buy it. Its biggest problem: false advertising. This is NOT a book on
> Python, it's about JYTHON - A Java based imitation of Python.
> >> Why? Well, there's some pretty software, available to download, which
> uses the the JRE. The author chose to stick with this "easy learning
> environment" and basically cripple anyone wanting to write Python code for
> Blender, Maya, Android etc.
> >>
> >> You may learn to program from this text, but don't expect a
> trouble-free life when you get exposed to the real language.
> >>
> >>
> >> The IDE that we wrote for the book, JES, is all Jython, and has been
> used by thousands of students for over a decade now: See
> http://cacm.acm.org/blogs/blog-cacm/205801-14-years-of-
> a-learner-centered-python-ide/fulltext
> >
> > So I'll just ask the obvious: CPython and Jython are supposed to be
> > alternative implementations of the same language, Python.  IronPython is
> > another.  How does a different implementation imply a different language?
> >
> > Andy
> >
> >
> >
> > ------------------------------------------------------------
> ------------------
> > _______________________________________________
> > Jython-users mailing list
> > Jyt...@li...
> > https://lists.sourceforge.net/lists/listinfo/jython-users
>
> ------------------------------------------------------------
> ------------------
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users
>

Re: [Jython-users] the health of Jython

[Adam B. <ada...@gm...>]

It doesn't, of course - it looks like a  reaction from a beginner who hasn't learnt to contextually separate a language from the platform surrounding it.

It might speak to the need for clearer doco entry points, though. The dominance (and usefulness) of stackoverflow for new programmers is also interesting. Because the foundation of jython predates it, there's not as much of a community around Jython there, that I've seen.

We made the wiki closed to anon edits because of nasty spam problems, but contributors are very welcome - just ask on this mailing list.

Adam

> 在 17 Sep 2016，8:32 AM，Michael Chisholm <chi...@mi...> 写道：
> 
> On 9/16/2016 1:13 PM, Guzdial, Mark wrote:
>>> Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead?
>> 
>> 
>> Actually, many of the students at University who are learning Python are actually learning Jython.  The textbook that Barbara Ericson and I wrote uses Jython: https://www.amazon.com/Introduction-Computing-Programming-Python-4th/dp/0134025547.  Last I saw market analysis, it's the third most popular Python University textbook, at least in the US.  If you read the reviews for the book, you'll see that lots of people are confused about Jython vs. Python.  Quoting one:
>> 
>> 
>> This book is a prescribed text for a course: that's the only reason to buy it. Its biggest problem: false advertising. This is NOT a book on Python, it's about JYTHON - A Java based imitation of Python.
>> Why? Well, there's some pretty software, available to download, which uses the the JRE. The author chose to stick with this "easy learning environment" and basically cripple anyone wanting to write Python code for Blender, Maya, Android etc.
>> 
>> You may learn to program from this text, but don't expect a trouble-free life when you get exposed to the real language.
>> 
>> 
>> The IDE that we wrote for the book, JES, is all Jython, and has been used by thousands of students for over a decade now: See http://cacm.acm.org/blogs/blog-cacm/205801-14-years-of-a-learner-centered-python-ide/fulltext
> 
> So I'll just ask the obvious: CPython and Jython are supposed to be 
> alternative implementations of the same language, Python.  IronPython is 
> another.  How does a different implementation imply a different language?
> 
> Andy
> 
> 
> 
> ------------------------------------------------------------------------------
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users

Re: [Jython-users] the health of Jython

[Michael C. <chi...@mi...>]

On 9/16/2016 1:13 PM, Guzdial, Mark wrote:
>> Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead?
>
>
> Actually, many of the students at University who are learning Python are actually learning Jython.  The textbook that Barbara Ericson and I wrote uses Jython: https://www.amazon.com/Introduction-Computing-Programming-Python-4th/dp/0134025547.  Last I saw market analysis, it's the third most popular Python University textbook, at least in the US.  If you read the reviews for the book, you'll see that lots of people are confused about Jython vs. Python.  Quoting one:
>
>
> This book is a prescribed text for a course: that's the only reason to buy it. Its biggest problem: false advertising. This is NOT a book on Python, it's about JYTHON - A Java based imitation of Python.
> Why? Well, there's some pretty software, available to download, which uses the the JRE. The author chose to stick with this "easy learning environment" and basically cripple anyone wanting to write Python code for Blender, Maya, Android etc.
>
> You may learn to program from this text, but don't expect a trouble-free life when you get exposed to the real language.
>
>
> The IDE that we wrote for the book, JES, is all Jython, and has been used by thousands of students for over a decade now: See http://cacm.acm.org/blogs/blog-cacm/205801-14-years-of-a-learner-centered-python-ide/fulltext
>

So I'll just ask the obvious: CPython and Jython are supposed to be 
alternative implementations of the same language, Python.  IronPython is 
another.  How does a different implementation imply a different language?

Andy

Re: [Jython-users] the health of Jython

[Guzdial, M. <gu...@cc...>]

> Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead?


Actually, many of the students at University who are learning Python are actually learning Jython.  The textbook that Barbara Ericson and I wrote uses Jython: https://www.amazon.com/Introduction-Computing-Programming-Python-4th/dp/0134025547.  Last I saw market analysis, it's the third most popular Python University textbook, at least in the US.  If you read the reviews for the book, you'll see that lots of people are confused about Jython vs. Python.  Quoting one:


This book is a prescribed text for a course: that's the only reason to buy it. Its biggest problem: false advertising. This is NOT a book on Python, it's about JYTHON - A Java based imitation of Python.
Why? Well, there's some pretty software, available to download, which uses the the JRE. The author chose to stick with this "easy learning environment" and basically cripple anyone wanting to write Python code for Blender, Maya, Android etc.

You may learn to program from this text, but don't expect a trouble-free life when you get exposed to the real language.


The IDE that we wrote for the book, JES, is all Jython, and has been used by thousands of students for over a decade now: See http://cacm.acm.org/blogs/blog-cacm/205801-14-years-of-a-learner-centered-python-ide/fulltext


- Mark

________________________________
From: Stefan Richthofer <Ste...@gm...>
Sent: Friday, September 16, 2016 9:53:28 AM
To: mro...@ya...
Cc: jyt...@li...
Subject: Re: [Jython-users] the health of Jython

Hello Mike,

completely agree with you in most points. Mainly I'd like to hint to the  https://wiki.python.org/jython/IrcChannel as an alternative for posting questions.
While not very active, it is at least rather responsive (usually within some hours or so).
I think a keypoint would be to bring the homepage and Wiki up to date. E.g. I once experienced it hard to find setup instructions to get pip etc running, install modules for Jython, including clarification how or how not this interfers with a CPython installation or modules installed via a package manager in Linux. Often enough such stuff is only implicitly documented via stackoverflow or so. There are rumors a new homepage is upcoming via github pages, but I don't know about an official statement.
Also the delay of Jython 2.7.1 isn't exactly beneficious for the issues you mention I guess.
It appears all in all this boils down to a lack of manpower for maintaining Jython. But I agree that maybe organization structures could actually be more friendly for contributing to the wiki or homepage and other documentation. We should definitely think this over!

> Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead?
A good starting point on this front would be an up-to-date getting-started-tutorial for Jython, including Java integration-hints. Maybe such a thing already exists somewhere (hints?), but I usually found such information rather spread over various places. Jython-book is usually the best source of information, but is also outdated and not exactly a tutorial. We would need something that covers Jython 2.7.

So much for now. Have a nice weekend!

-Stefan

Gesendet: Donnerstag, 15. September 2016 um 20:48 Uhr
Von: "Mike Rodent" <mro...@ya...>
An: "jyt...@li..." <jyt...@li...>
Betreff: [Jython-users] the health of Jython
I love Jython ... and I think you people who develop it are geniuses.

But just looking at the archives for this mailing list tells its own story.  In the early years you see hundreds of posts a month sometimes... in the whole of March this year there was precisely ONE post.

As I understand it, Jython was quite actively developed in its early years, and then went a bit quiet, but is now getting developed quite actively (no doubt Jython 3 will provoke some more interest).  And yet there is nothing but this mailing list to pose questions, etc.

Does no-one here think that a mailing list as the centre of the Jython community is slightly anachronistic in 2016?  Wouldn't a simple forum tend to encourage new users to sniff out the power of the language?

The goodness of Jython should be evangelised!  Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead?

Just a thought!
Mike

------------------------------------------------------------------------------ _______________________________________________ Jython-users mailing list Jyt...@li... https://lists.sourceforge.net/lists/listinfo/jython-users

Re: [Jython-users] the health of Jython

[Curtis R. <ctr...@wi...>]

Hi everyone,

>From my naive outsider perspective, the #1 thing that would invigorate the
Jython project is the ability to seamless use modules from the CPython
world. If JyNI (http://jyni.org/) can fulfill this promise, many more
people in the scientific community and beyond could then combine the JVM
with powerful Python libraries like numpy, scipy and skimage. For me
personally, this would alleviate a lot of the stress of continually needing
to "choose a side" when developing tech for scientists.

As for mailing lists + IRC vs. forums, I agree that mailing lists are
dated, and not really welcoming to new members of the tech community. A
mailing list basically says "this project has been around for a long time
-- it is the way it is, and if you don't like it, use something else." My
community (http://imagej.net/) recently transitioned support for our whole
OSS software stack from mailing lists + IRC over to Discourse + Gitter, and
the results have been astoundingly successful. I hated forum software for
many years, but would wholeheartedly recommend Discourse, which is a
quantum leap forward in both civil discussion and usability.

Regards,
Curtis

--
Curtis Rueden
LOCI software architect - http://loci.wisc.edu/software
ImageJ2 lead, Fiji maintainer - http://imagej.net/User:Rueden
Did you know ImageJ has a forum? http://forum.imagej.net/


On Fri, Sep 16, 2016 at 6:53 AM, Stefan Richthofer <Ste...@gm...
> wrote:

> Hello Mike,
>
> completely agree with you in most points. Mainly I'd like to hint to the
> https://wiki.python.org/jython/IrcChannel as an alternative for posting
> questions.
> While not very active, it is at least rather responsive (usually within
> some hours or so).
> I think a keypoint would be to bring the homepage and Wiki up to date.
> E.g. I once experienced it hard to find setup instructions to get pip etc
> running, install modules for Jython, including clarification how or how not
> this interfers with a CPython installation or modules installed via a
> package manager in Linux. Often enough such stuff is only implicitly
> documented via stackoverflow or so. There are rumors a new homepage is
> upcoming via github pages, but I don't know about an official statement.
> Also the delay of Jython 2.7.1 isn't exactly beneficious for the issues
> you mention I guess.
> It appears all in all this boils down to a lack of manpower for
> maintaining Jython. But I agree that maybe organization structures could
> actually be more friendly for contributing to the wiki or homepage and
> other documentation. We should definitely think this over!
>
> > Apparently a lot of new programmers are being introduced to programming
> through CPython ... shouldn't the poor kids be learning Jython instead?
> A good starting point on this front would be an up-to-date
> getting-started-tutorial for Jython, including Java integration-hints.
> Maybe such a thing already exists somewhere (hints?), but I usually found
> such information rather spread over various places. Jython-book is usually
> the best source of information, but is also outdated and not exactly a
> tutorial. We would need something that covers Jython 2.7.
>
> So much for now. Have a nice weekend!
>
> -Stefan
>
> *Gesendet:* Donnerstag, 15. September 2016 um 20:48 Uhr
> *Von:* "Mike Rodent" <mro...@ya...>
> *An:* "jyt...@li..." <jython-users@lists.
> sourceforge.net>
> *Betreff:* [Jython-users] the health of Jython
> I love Jython ... and I think you people who develop it are geniuses.
>
> But just looking at the archives for this mailing list tells its own
> story.  In the early years you see hundreds of posts a month sometimes...
> in the whole of March this year there was precisely ONE post.
>
> As I understand it, Jython was quite actively developed in its early
> years, and then went a bit quiet, but is now getting developed quite
> actively (no doubt Jython 3 will provoke some more interest).  And yet
> there is nothing but this mailing list to pose questions, etc.
>
> Does no-one here think that a mailing list as the centre of the Jython
> community is slightly anachronistic in 2016?  Wouldn't a simple forum tend
> to encourage new users to sniff out the power of the language?
>
> The goodness of Jython should be evangelised!  Apparently a lot of new
> programmers are being introduced to programming through CPython ...
> shouldn't the poor kids be learning Jython instead?
>
> Just a thought!
> Mike
>
> ------------------------------------------------------------------------------
> _______________________________________________ Jython-users mailing list
> Jyt...@li... https://lists.sourceforge.net/
> lists/listinfo/jython-users
>
> ------------------------------------------------------------
> ------------------
>
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users
>
>

Re: [Jython-users] the health of Jython

[Stefan R. <Ste...@gm...>]

<html><head></head><body><div style="font-family: Verdana;font-size: 12.0px;"><div>
<div>Hello Mike,</div>

<div>&nbsp;</div>

<div>completely agree with you in most points. Mainly I&#39;d like to hint to the&nbsp; <a href="https://wiki.python.org/jython/IrcChannel" target="_blank">https://wiki.python.org/jython/IrcChannel</a> as an alternative for posting questions.</div>

<div>While not very active, it is at least rather responsive (usually within some hours or so).</div>

<div>I think a keypoint would be to bring the homepage and Wiki up to date. E.g. I once experienced it hard to find setup instructions to get pip etc running, install modules for Jython, including clarification how or how not this interfers with a CPython installation or modules installed via a package manager in Linux. Often enough such stuff is only implicitly documented via stackoverflow or so. There are rumors a new homepage is upcoming via github pages, but I don&#39;t know about an official statement.</div>

<div>Also the delay of Jython 2.7.1 isn&#39;t exactly beneficious for the issues you mention I guess.</div>

<div>It appears all in all this boils down to a lack of manpower for maintaining Jython. But I agree that maybe organization structures could actually be more friendly for contributing to the wiki or homepage and other documentation. We should definitely think this over!</div>

<div>&nbsp;</div>

<div>&gt; Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn&#39;t the poor kids be learning Jython instead?</div>

<div>A good starting point on this front would be an up-to-date getting-started-tutorial for Jython, including Java integration-hints. Maybe such a thing already exists somewhere (hints?), but I usually found such information rather spread over various places. Jython-book is usually the best source of information, but is also outdated and not exactly a tutorial. We would need something that covers Jython 2.7.</div>

<div>&nbsp;</div>

<div>So much for now. Have a nice weekend!</div>

<div>&nbsp;</div>

<div>-Stefan</div>

<div>&nbsp;
<div style="margin: 10.0px 5.0px 5.0px 10.0px;padding: 10.0px 0 10.0px 10.0px;border-left: 2.0px solid rgb(195,217,229);">
<div style="margin: 0 0 10.0px 0;"><b>Gesendet:</b>&nbsp;Donnerstag, 15. September 2016 um 20:48 Uhr<br/>
<b>Von:</b>&nbsp;&quot;Mike Rodent&quot; &lt;mro...@ya...&gt;<br/>
<b>An:</b>&nbsp;&quot;jyt...@li...&quot; &lt;jyt...@li...&gt;<br/>
<b>Betreff:</b>&nbsp;[Jython-users] the health of Jython</div>

<div>
<div style="color: rgb(0,0,0);background-color: rgb(255,255,255);font-family: Courier New , courier , monaco , monospace , sans-serif;font-size: 13.0px;">
<div id="yui_3_16_0_ym19_1_1473964808496_3003">I love Jython ... and I think you people who develop it are geniuses.</div>

<div id="yui_3_16_0_ym19_1_1473964808496_3004">&nbsp;</div>

<div id="yui_3_16_0_ym19_1_1473964808496_3005">But just looking at the archives for this mailing list tells its own story.&nbsp; In the early years you see hundreds of posts a month sometimes... in the whole of March this year there was precisely ONE post.</div>

<div id="yui_3_16_0_ym19_1_1473964808496_3058">&nbsp;</div>
As I understand it, Jython was quite actively developed in its early years, and then went a bit quiet, but is now getting developed quite actively (no doubt Jython 3 will provoke some more interest).&nbsp; And yet there is nothing but this mailing list to pose questions, etc.

<div>&nbsp;</div>

<div id="yui_3_16_0_ym19_1_1473964808496_3121">Does no-one here think that a mailing list as the centre of the Jython community is slightly anachronistic in 2016?&nbsp; Wouldn&#39;t a simple forum tend to encourage new users to sniff out the power of the language?</div>

<div id="yui_3_16_0_ym19_1_1473964808496_3122">&nbsp;</div>

<div>The goodness of Jython should be evangelised!&nbsp; Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn&#39;t the poor kids be learning Jython instead?</div>

<div>&nbsp;</div>

<div>Just a thought!</div>

<div>Mike</div>

<div id="yui_3_16_0_ym19_1_1473964808496_2928">&nbsp;</div>
</div>
------------------------------------------------------------------------------ _______________________________________________ Jython-users mailing list Jyt...@li... <a href="https://lists.sourceforge.net/lists/listinfo/jython-users" target="_blank">https://lists.sourceforge.net/lists/listinfo/jython-users</a></div>
</div>
</div>
</div></div></body></html>

[Jython-users] Web server

[Mike R. <mro...@ya...>]

(last question)
Just wondering what the Jython experts use as a rule for a Web server technology: Django from the Python universe, or Tomcat from the Java one, or something else?  Care to say why?

[Jython-users] Daemon thread/process?

[Mike R. <mro...@ya...>]

Now for a real question:
I recently started learning Gradle, which uses Groovy (a horrible heresy of a language: halfway to Jython but really just syntactic sugar.  They should have used Jython of course).
By setting a directive in the "properties" file (there are other ways of doing it) you can get Groovy to set up all the Java stuff in memory persistently... meaning that it is only the first time you run your Groovy program that it takes a long time.  After that it is very fast.

I believe it is true to say that one thing which is (very) offputting about Jython to those new to it is that, compared to CPython or Java, it takes a long time to just run... because all these Java classes have to be loaded into memory each time.
Is there no way this sort of thing could be implemented for Jython?  I tried to get to grips with Nailgun with a view to this a couple of years ago, but it was beyond my skill level.

[Jython-users] the health of Jython

[Mike R. <mro...@ya...>]

I love Jython ... and I think you people who develop it are geniuses.
But just looking at the archives for this mailing list tells its own story.  In the early years you see hundreds of posts a month sometimes... in the whole of March this year there was precisely ONE post.
As I understand it, Jython was quite actively developed in its early years, and then went a bit quiet, but is now getting developed quite actively (no doubt Jython 3 will provoke some more interest).  And yet there is nothing but this mailing list to pose questions, etc.
Does no-one here think that a mailing list as the centre of the Jython community is slightly anachronistic in 2016?  Wouldn't a simple forum tend to encourage new users to sniff out the power of the language?
The goodness of Jython should be evangelised!  Apparently a lot of new programmers are being introduced to programming through CPython ... shouldn't the poor kids be learning Jython instead?

Just a thought!Mike

Re: [Jython-users] Possible bug in cert validation? _sslcerts.py

[Darjus L. <da...@gm...>]

http://bugs.jython.org/issue2516

On Mon, Aug 29, 2016 at 9:53 AM Darjus Loktevic <da...@gm...> wrote:

> Hey Craig,
>
> Thanks for the detailed description. This definitely sounds like a bug.
> Since Jython isn't using OpenSSL, we have to emulate it's behavior and so
> far it's been quite challenging to right especially with the relatively few
> tests that we have.
>
> The situation we're trying to emulate, is this:
> https://github.com/openssl/openssl/blob/master/crypto/x509/x509_cmp.c#L279
>
> There they have a cert already associated with the private key, which
> makes it an easier lookup. In our case we had to do the check before
> loading into a key store (don't remember the exact reasoning).
> The code is of course wrong in assuming there is only a private/public key
> match.
>
> So, the quick "fix" is to see if there's at least one cert matching in the
> file.
> I'll update the issue with the fix.
>
> Cheers,
> Darjus
>
> On Thu, Aug 25, 2016 at 12:33 AM Craig McDaniel <
> cra...@da...> wrote:
>
>> I have potentially found one or more bugs in _sslcerts.py, but before I
>> file a bug report, I would like to get some context and possibly understand
>> the intent of the code in question, as I am not an SSL expert.
>>
>> First, my use case: I have a customer that has a chain of SSL certs in a
>> PEM file. It includes the leaf cert, then 2 intermediate certs, and finally
>> their own root CA cert (which they've manually added as a trusted cert in
>> their browsers throughout their org). When trying to establish an SSL
>> server connection, the function _get_open_ssl_key_manager tries to validate
>> that the private and public keys match, and is throwing an SSLError: "key
>> values mismatch". This same chain of certs worked fine when we were on
>> CPython and using pyOpenSSL.
>>
>> I have traced the root cause. In _get_open_ssl_key_manager, it is looping
>> over all the certs from the cert_file and checking that the modulus from
>> the private key matches the modulus of the public key. However, this is
>> only true for the first cert (the leaf). I am going to paste the code here,
>> because it looks very suspect to me:
>>
>>    keys_match = False
>>    for cert in certs:
>>        # TODO works for RSA only for now
>>        if not isinstance(cert.publicKey, RSAPublicKey) and
>> isinstance(private_key, RSAPrivateCrtKey):
>>            keys_match = True
>>            continue
>>
>>        if cert.publicKey.getModulus() == private_key.getModulus() \
>>                and cert.publicKey.getPublicExponent() ==
>> private_key.getPublicExponent():
>>            keys_match = True
>>        else:
>>            keys_match = False
>>
>>    if key_file is not None and not keys_match:
>>        from _socket import SSLError, SSL_ERROR_SSL
>>        raise SSLError(SSL_ERROR_SSL, "key values mismatch")
>>
>> The first condition in the loop is always false for my case. This isn't
>> what bothers me. The keys_match flag is True on the first iteration of the
>> loop, then False, False, False. Certainly this is not what is intended
>> here. In fact, my co-worker reversed the order of the certs in the PEM
>> file, and thus avoided the Error. The server started, but the browser
>> simply would not recognize it as a valid cert chain (couldn't even accept
>> it as a security exception).
>>
>> It is theoretically possible that the 2nd or 3rd cert in the chain could
>> pass the modulus check. The result would still be False after having
>> temporarily been True. What does this mean? What is the intention here?
>> Should it simply break out of the loop the first time it finds a match?
>> Perhaps the problem is elsewhere...
>>
>> So I looked a little deeper. Just before this loop:
>>
>>     if cert_file is not None:
>>         _certs, _private_key = _extract_certs_for_paths([cert_file],
>> password)
>>         private_key = _private_key if _private_key else private_key
>>         certs.extend(_certs)
>>
>> Now, _extract_certs_for_paths does something interesting. It calls
>> _extract_certs_from_keystore_file in a try/except block, and if it fails,
>> it then tries _extract_cert_from_data, which reads it as a PEM file.
>> Curious, I decided to convert the PEM file to a JKS keystore. This actually
>> worked, and here I found an important difference between these 2 functions.
>>
>> 1. _extract_certs_from_keystore_file returns only the leaf cert. I
>> verified that the JKS file has the full chain with keytool -list -v.
>> Apparently keystore.getCertificate(alias) only returns the leaf. Thus the
>> JKS file passes the check. However, it also loops over the aliases in the
>> keystore, so if I had more than one key in the store, we would again have
>> potential breakage.
>>
>> 2. _extract_cert_from_data returns all 4 certs in the chain. Thus the PEM
>> file fails the check because the last (root) cert causes keys_match to be
>> False.
>>
>> Notice also (now I'm knit-picking) the plurality of the word "cert(s)" is
>> even backwards considering how the 2 functions actually behave.
>>
>> Before I file this as a bug, I would like to find out if anyone has some
>> perspective to add. This certainly feels like one or more bugs to me, but
>> as I said before - I am not an SSL expert.
>>
>>
>> ------------------------------------------------------------------------------
>> _______________________________________________
>> Jython-users mailing list
>> Jyt...@li...
>> https://lists.sourceforge.net/lists/listinfo/jython-users
>>
>

Re: [Jython-users] Possible bug in cert validation? _sslcerts.py

[Darjus L. <da...@gm...>]

Hey Craig,

Thanks for the detailed description. This definitely sounds like a bug.
Since Jython isn't using OpenSSL, we have to emulate it's behavior and so
far it's been quite challenging to right especially with the relatively few
tests that we have.

The situation we're trying to emulate, is this:
https://github.com/openssl/openssl/blob/master/crypto/x509/x509_cmp.c#L279

There they have a cert already associated with the private key, which makes
it an easier lookup. In our case we had to do the check before loading into
a key store (don't remember the exact reasoning).
The code is of course wrong in assuming there is only a private/public key
match.

So, the quick "fix" is to see if there's at least one cert matching in the
file.
I'll update the issue with the fix.

Cheers,
Darjus

On Thu, Aug 25, 2016 at 12:33 AM Craig McDaniel <cra...@da...>
wrote:

> I have potentially found one or more bugs in _sslcerts.py, but before I
> file a bug report, I would like to get some context and possibly understand
> the intent of the code in question, as I am not an SSL expert.
>
> First, my use case: I have a customer that has a chain of SSL certs in a
> PEM file. It includes the leaf cert, then 2 intermediate certs, and finally
> their own root CA cert (which they've manually added as a trusted cert in
> their browsers throughout their org). When trying to establish an SSL
> server connection, the function _get_open_ssl_key_manager tries to validate
> that the private and public keys match, and is throwing an SSLError: "key
> values mismatch". This same chain of certs worked fine when we were on
> CPython and using pyOpenSSL.
>
> I have traced the root cause. In _get_open_ssl_key_manager, it is looping
> over all the certs from the cert_file and checking that the modulus from
> the private key matches the modulus of the public key. However, this is
> only true for the first cert (the leaf). I am going to paste the code here,
> because it looks very suspect to me:
>
>    keys_match = False
>    for cert in certs:
>        # TODO works for RSA only for now
>        if not isinstance(cert.publicKey, RSAPublicKey) and
> isinstance(private_key, RSAPrivateCrtKey):
>            keys_match = True
>            continue
>
>        if cert.publicKey.getModulus() == private_key.getModulus() \
>                and cert.publicKey.getPublicExponent() ==
> private_key.getPublicExponent():
>            keys_match = True
>        else:
>            keys_match = False
>
>    if key_file is not None and not keys_match:
>        from _socket import SSLError, SSL_ERROR_SSL
>        raise SSLError(SSL_ERROR_SSL, "key values mismatch")
>
> The first condition in the loop is always false for my case. This isn't
> what bothers me. The keys_match flag is True on the first iteration of the
> loop, then False, False, False. Certainly this is not what is intended
> here. In fact, my co-worker reversed the order of the certs in the PEM
> file, and thus avoided the Error. The server started, but the browser
> simply would not recognize it as a valid cert chain (couldn't even accept
> it as a security exception).
>
> It is theoretically possible that the 2nd or 3rd cert in the chain could
> pass the modulus check. The result would still be False after having
> temporarily been True. What does this mean? What is the intention here?
> Should it simply break out of the loop the first time it finds a match?
> Perhaps the problem is elsewhere...
>
> So I looked a little deeper. Just before this loop:
>
>     if cert_file is not None:
>         _certs, _private_key = _extract_certs_for_paths([cert_file],
> password)
>         private_key = _private_key if _private_key else private_key
>         certs.extend(_certs)
>
> Now, _extract_certs_for_paths does something interesting. It calls
> _extract_certs_from_keystore_file in a try/except block, and if it fails,
> it then tries _extract_cert_from_data, which reads it as a PEM file.
> Curious, I decided to convert the PEM file to a JKS keystore. This actually
> worked, and here I found an important difference between these 2 functions.
>
> 1. _extract_certs_from_keystore_file returns only the leaf cert. I
> verified that the JKS file has the full chain with keytool -list -v.
> Apparently keystore.getCertificate(alias) only returns the leaf. Thus the
> JKS file passes the check. However, it also loops over the aliases in the
> keystore, so if I had more than one key in the store, we would again have
> potential breakage.
>
> 2. _extract_cert_from_data returns all 4 certs in the chain. Thus the PEM
> file fails the check because the last (root) cert causes keys_match to be
> False.
>
> Notice also (now I'm knit-picking) the plurality of the word "cert(s)" is
> even backwards considering how the 2 functions actually behave.
>
> Before I file this as a bug, I would like to find out if anyone has some
> perspective to add. This certainly feels like one or more bugs to me, but
> as I said before - I am not an SSL expert.
>
>
> ------------------------------------------------------------------------------
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users
>

Re: [Jython-users] Servlet ImportError: Cannot import site module and its dependencies: No module named site

[Alan K. <jyt...@xh...>]

Hi David.

The modjy documentation has a fair amount of detail about running jython
inside servlet containers. Although the docs are for modjy, the
configuration details described are also generally applicable to running
jython in servlet containers.

These two pages should contain relevant information.

http://opensource.xhaus.com/projects/modjy/wiki/ModjyDeployment
http://opensource.xhaus.com/projects/modjy/wiki/ModjyTroubleShooting

The relevant java code that controls all of this is here

https://hg.python.org/jython/file/tip/src/com/xhaus/modjy/ModjyJServlet.java

In particular, it looks like you should be looking at the jython registry,
how it is located and what values it contains.

https://wiki.python.org/jython/UserGuide#finding-the-registry-file
http://www.jython.org/jythonbook/en/1.0/appendixA.html

Lastly, is there a reason why you don't want to use modjy? It is custom
designed for running jython application inside servlet containers,
specifically WSGI applications.

Regards,

Alan.


On Tue, Aug 23, 2016 at 11:21 PM, David Charles <dav...@gm...>
wrote:

> I just created my first servlet in Jython2.7.0 running on
> Apache2/Tomcat6.  When I tried to access my servlet with my browser, I got
> the following error message:
>
> HTTP Status 500 - Servlet.init() for servlet PyServlet threw exception
> ------------------------------
>
> *type* Exception report
>
> *message* *Servlet.init() for servlet PyServlet threw exception*
>
> *description* *The server encountered an internal error that prevented it
> from fulfilling this request.*
>
> *exception*
>
> javax.servlet.ServletException: Servlet.init() for servlet PyServlet threw exception
> 	org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
> 	org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
> 	org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
> 	org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606)
> 	org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
> 	java.lang.Thread.run(Thread.java:745)
>
> *root cause*
>
> ImportError: Cannot import site module and its dependencies: No module named site
> Determine if the following attributes are correct:
>   * sys.path: ['/var/lib/tomcat6/webapps/jythonsample/WEB-INF/lib/Lib', '__classpath__', '__pyclasspath__/']
>     This attribute might be including the wrong directories, such as from CPython
>   * sys.prefix: /var/lib/tomcat6/webapps/jythonsample/WEB-INF/lib
>     This attribute is set by the system property python.home, although it can
>     be often automatically determined by the location of the Jython jar file
>
> You can use the -S option or python.import.site=false to not import the site module
>
> 	org.python.core.Py.ImportError(Py.java:328)
> 	org.python.core.Py.importSiteIfSelected(Py.java:1563)
> 	org.python.util.PythonInterpreter.<init>(PythonInterpreter.java:116)
> 	org.python.util.PythonInterpreter.<init>(PythonInterpreter.java:94)
> 	org.python.util.PyServlet.createInterpreter(PyServlet.java:124)
> 	org.python.util.PyServlet.reset(PyServlet.java:170)
> 	org.python.util.PyServlet.init(PyServlet.java:90)
> 	javax.servlet.GenericServlet.init(GenericServlet.java:212)
> 	org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
> 	org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
> 	org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
> 	org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606)
> 	org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
> 	java.lang.Thread.run(Thread.java:745)
>
> *note* *The full stack trace of the root cause is available in the Apache
> Tomcat/6.0.39 logs.*
> ------------------------------
> Apache Tomcat/6.0.39This is a web application, so I am not using the
> command-line interface (so I cannot pass -S), nor am I starting the
> interpreter from some Java code (so I cannot set property
> python.import.site).
>
> As a quick experiment, I copied the my $JYTHON_HOME/Lib directory into
> jythonsample/WEB-INF/libs and this made the ImportError go away.
> Symlinking the $JYTHON_HOME/Lib directory also made the ImportError go
> away.  But, both of these solutions seem dubious to me.  If I copy the Lib
> folder I feel like I have greater certainty that jython.jar and the Lib
> directory are a matched set, but my Lib directory is 99M in size!  If I
> symlink the Lib folder, I save the 99M but I lose the certainty that I have
> a matching jython.jar and Lib directory.
>
> I have also considered creating a custom jython.jar that contains Lib, or
> learning how to have a single, common jython.jar (and Lib) for all of my
> servlets, but before I head down those paths I thought I would ask to see
> what other people are doing.
>
> David
>
>
>
> ------------------------------------------------------------
> ------------------
>
> _______________________________________________
> Jython-users mailing list
> Jyt...@li...
> https://lists.sourceforge.net/lists/listinfo/jython-users
>
>

[Jython-users] Possible bug in cert validation? _sslcerts.py

[Craig M. <cra...@da...>]

I have potentially found one or more bugs in _sslcerts.py, but before I
file a bug report, I would like to get some context and possibly understand
the intent of the code in question, as I am not an SSL expert.

First, my use case: I have a customer that has a chain of SSL certs in a
PEM file. It includes the leaf cert, then 2 intermediate certs, and finally
their own root CA cert (which they've manually added as a trusted cert in
their browsers throughout their org). When trying to establish an SSL
server connection, the function _get_open_ssl_key_manager tries to validate
that the private and public keys match, and is throwing an SSLError: "key
values mismatch". This same chain of certs worked fine when we were on
CPython and using pyOpenSSL.

I have traced the root cause. In _get_open_ssl_key_manager, it is looping
over all the certs from the cert_file and checking that the modulus from
the private key matches the modulus of the public key. However, this is
only true for the first cert (the leaf). I am going to paste the code here,
because it looks very suspect to me:

   keys_match = False
   for cert in certs:
       # TODO works for RSA only for now
       if not isinstance(cert.publicKey, RSAPublicKey) and
isinstance(private_key, RSAPrivateCrtKey):
           keys_match = True
           continue

       if cert.publicKey.getModulus() == private_key.getModulus() \
               and cert.publicKey.getPublicExponent() ==
private_key.getPublicExponent():
           keys_match = True
       else:
           keys_match = False

   if key_file is not None and not keys_match:
       from _socket import SSLError, SSL_ERROR_SSL
       raise SSLError(SSL_ERROR_SSL, "key values mismatch")

The first condition in the loop is always false for my case. This isn't
what bothers me. The keys_match flag is True on the first iteration of the
loop, then False, False, False. Certainly this is not what is intended
here. In fact, my co-worker reversed the order of the certs in the PEM
file, and thus avoided the Error. The server started, but the browser
simply would not recognize it as a valid cert chain (couldn't even accept
it as a security exception).

It is theoretically possible that the 2nd or 3rd cert in the chain could
pass the modulus check. The result would still be False after having
temporarily been True. What does this mean? What is the intention here?
Should it simply break out of the loop the first time it finds a match?
Perhaps the problem is elsewhere...

So I looked a little deeper. Just before this loop:

    if cert_file is not None:
        _certs, _private_key = _extract_certs_for_paths([cert_file],
password)
        private_key = _private_key if _private_key else private_key
        certs.extend(_certs)

Now, _extract_certs_for_paths does something interesting. It calls
_extract_certs_from_keystore_file in a try/except block, and if it fails,
it then tries _extract_cert_from_data, which reads it as a PEM file.
Curious, I decided to convert the PEM file to a JKS keystore. This actually
worked, and here I found an important difference between these 2 functions.

1. _extract_certs_from_keystore_file returns only the leaf cert. I verified
that the JKS file has the full chain with keytool -list -v. Apparently
keystore.getCertificate(alias) only returns the leaf. Thus the JKS file
passes the check. However, it also loops over the aliases in the keystore,
so if I had more than one key in the store, we would again have potential
breakage.

2. _extract_cert_from_data returns all 4 certs in the chain. Thus the PEM
file fails the check because the last (root) cert causes keys_match to be
False.

Notice also (now I'm knit-picking) the plurality of the word "cert(s)" is
even backwards considering how the 2 functions actually behave.

Before I file this as a bug, I would like to find out if anyone has some
perspective to add. This certainly feels like one or more bugs to me, but
as I said before - I am not an SSL expert.

[Jython-users] Servlet ImportError: Cannot import site module and its dependencies: No module named site

[David C. <dav...@gm...>]

I just created my first servlet in Jython2.7.0 running on Apache2/Tomcat6.
When I tried to access my servlet with my browser, I got the following
error message:

HTTP Status 500 - Servlet.init() for servlet PyServlet threw exception
------------------------------

*type* Exception report

*message* *Servlet.init() for servlet PyServlet threw exception*

*description* *The server encountered an internal error that prevented it
from fulfilling this request.*

*exception*

javax.servlet.ServletException: Servlet.init() for servlet PyServlet
threw exception
	org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
	org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
	org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
	org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606)
	org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
	java.lang.Thread.run(Thread.java:745)

*root cause*

ImportError: Cannot import site module and its dependencies: No module
named site
Determine if the following attributes are correct:
  * sys.path: ['/var/lib/tomcat6/webapps/jythonsample/WEB-INF/lib/Lib',
'__classpath__', '__pyclasspath__/']
    This attribute might be including the wrong directories, such as
from CPython
  * sys.prefix: /var/lib/tomcat6/webapps/jythonsample/WEB-INF/lib
    This attribute is set by the system property python.home, although it can
    be often automatically determined by the location of the Jython jar file

You can use the -S option or python.import.site=false to not import
the site module

	org.python.core.Py.ImportError(Py.java:328)
	org.python.core.Py.importSiteIfSelected(Py.java:1563)
	org.python.util.PythonInterpreter.<init>(PythonInterpreter.java:116)
	org.python.util.PythonInterpreter.<init>(PythonInterpreter.java:94)
	org.python.util.PyServlet.createInterpreter(PyServlet.java:124)
	org.python.util.PyServlet.reset(PyServlet.java:170)
	org.python.util.PyServlet.init(PyServlet.java:90)
	javax.servlet.GenericServlet.init(GenericServlet.java:212)
	org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
	org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
	org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
	org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606)
	org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
	java.lang.Thread.run(Thread.java:745)

*note* *The full stack trace of the root cause is available in the Apache
Tomcat/6.0.39 logs.*
------------------------------
Apache Tomcat/6.0.39This is a web application, so I am not using the
command-line interface (so I cannot pass -S), nor am I starting the
interpreter from some Java code (so I cannot set property
python.import.site).

As a quick experiment, I copied the my $JYTHON_HOME/Lib directory into
jythonsample/WEB-INF/libs and this made the ImportError go away.
Symlinking the $JYTHON_HOME/Lib directory also made the ImportError go
away.  But, both of these solutions seem dubious to me.  If I copy the Lib
folder I feel like I have greater certainty that jython.jar and the Lib
directory are a matched set, but my Lib directory is 99M in size!  If I
symlink the Lib folder, I save the 99M but I lose the certainty that I have
a matching jython.jar and Lib directory.

I have also considered creating a custom jython.jar that contains Lib, or
learning how to have a single, common jython.jar (and Lib) for all of my
servlets, but before I head down those paths I thought I would ask to see
what other people are doing.

David

Re: [Jython-users] CPython 3.x

[<fwi...@gm...>]

On Tue, Aug 23, 2016 at 3:42 AM, DanglingPointer
<dan...@gm...> wrote:
> Was wondering if CPyhton 3.x is in Jython's roadmap at all?
Things are moving, but it will still be a while before we'd even want
to dare call it "alpha" :) I'm hoping to put out some kind of alpha
somewhere in the next month or two.

-Frank