jython-users

Re: [Jython-users] java.lang.String becomes PyString

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

Maybe you should consider what is really 
happening and consider just to change your
tests:

>>> from java import util,lang
>>> import Cont
>>> c=Cont()
>>> c.set("a")
>>> c.get()
'a'
>>> c.get().__class__
<jclass org.python.core.PyString at 387569>
>>> c.check()
a of java.lang.String
>>> c.set(lang.String("a"))
>>> c.get()
'a'
>>> c.get().__class__
<jclass org.python.core.PyString at 387569>
>>> c.check()
a of java.lang.String

[this behaviour is very unlikey to change]

where Cont is:

public class Cont {

 private Object obj;

 public void set(Object obj) { this.obj = obj; }

 public Object get() { return obj; }

 public void check() {
   System.out.println(obj + " of " + obj.getClass().getName());
 }

}

So yes a java.lang.String becomes a PyString but
also a PyString becomes a java.lang.String when Object
is expected.

regards, Samuele Pedroni.

RE: [Jython-users] java.lang.String becomes PyString

[Delaney, T. <tde...@av...>]

> From: Edward Povazan [mailto:epo...@te...]
> 
> Thanks for the explanation.
> I now understand that obj is a String on the java side, but a 
> PyString on
> the jython side.
> The reason I was asking is that I create my user interface widgets in
> Jython, which includes many custom controls, and sometimes I 
> need to do
> object.toString() which of course fails on a PyString.
> So I need a wrapper around string objects ... a little 
> annoying. Oh well.

If you are doing object.toString() in the Python code, you should instead
use str(object).

Tim Delaney

Re: [Jython-users] java.lang.String becomes PyString

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

From: Delaney, Timothy <tde...@av...>
> > From: Edward Povazan [mailto:epo...@te...]
> > 
> > Thanks for the explanation.
> > I now understand that obj is a String on the java side, but a 
> > PyString on
> > the jython side.
> > The reason I was asking is that I create my user interface widgets in
> > Jython, which includes many custom controls, and sometimes I 
> > need to do
> > object.toString() which of course fails on a PyString.
> > So I need a wrapper around string objects ... a little 
> > annoying. Oh well.
> 
> If you are doing object.toString() in the Python code, you should instead
> use str(object).
> 

True. I can only add that if you subclass a Java class from Jython
then you should define both toString and __repr__/__str__,
toString for java side and the other to make str work.

regards, Samuele Pedroni.

Re: [Jython-users] java.lang.String becomes PyString

[Edward P. <epo...@te...>]

Thanks for the explanation.
I now understand that obj is a String on the java side, but a PyString on
the jython side.
The reason I was asking is that I create my user interface widgets in
Jython, which includes many custom controls, and sometimes I need to do
object.toString() which of course fails on a PyString.
So I need a wrapper around string objects ... a little annoying. Oh well.

-Ed