Comments on: Using Java2Python to port a JavaCairo tutorial

By: stu

stu — Mon, 30 Nov 2009 05:12:02 +0000

I had a bit of a go at this on the weekend.
The current version of the java-gnome bindings is 4.x, for a while ubuntu had the old bindings installed (my test vm seems to).

To check which version you have look in
/usr/share/java
gtk-4.0.jar Is the correct version
gtk2.10 Is the old version

I managed dist-upgrade my ubuntu to karmic koala, but

$ sudo apt-get upgrade libjava-gnome-java

Was still not enough… however:

$ sudo apt-get remove libjava-gnome-java
$ sudo apt-get install libjava-gnome-java

DID install gtk-4.0.jar.

You may need to manually set the classpath:

$ export CLASSPATH=/usr/share/java/gtk-4.0.jar

Unfortunately I don’t have the vm I used to write this tutorial with at the moment, so it’s a little tricky to test stuff – if I get time I’ll try and get everything working again and fix any gaps in the tutorial.

By: stu

stu — Thu, 26 Nov 2009 20:52:29 +0000

Hi,
The first problem is because the file is called Gsimple.java, not GSimple.java (notice the second ‘s’ should be uppercase).

The other errors look like java gnome is not in the classpath.

By: Oscar

Oscar — Thu, 26 Nov 2009 19:20:49 +0000

Hi again,
there are my errors:
javac Gsimple.java
Gsimple.java:21: class GSimple is public, should be declared in a file named GSimple.java
public class GSimple extends Window {
^
Gsimple.java:3: package org.gnome.gdk does not exist
import org.gnome.gdk.Event;
^
Gsimple.java:4: package org.gnome.gtk does not exist
import org.gnome.gtk.Gtk;
^
Gsimple.java:5: package org.gnome.gtk does not exist
import org.gnome.gtk.Widget;
^
Gsimple.java:6: package org.gnome.gtk does not exist
import org.gnome.gtk.Window;
^
Gsimple.java:7: package org.gnome.gtk does not exist
import org.gnome.gtk.WindowPosition;
^
Gsimple.java:21: cannot find symbol
symbol: class Window
public class GSimple extends Window {
^
Gsimple.java:25: cannot find symbol
symbol : method setTitle(java.lang.String)
location: class com.zetcode.GSimple
setTitle(“Simple”);
^
Gsimple.java:27: package Window does not exist
connect(new Window.DeleteEvent() {
^
Gsimple.java:34: cannot find symbol
symbol : method setDefaultSize(int,int)
location: class com.zetcode.GSimple
setDefaultSize(250, 150);
^
Gsimple.java:35: cannot find symbol
symbol : variable WindowPosition
location: class com.zetcode.GSimple
setPosition(WindowPosition.CENTER);
^
Gsimple.java:36: cannot find symbol
symbol : method show()
location: class com.zetcode.GSimple
show();
^
Gsimple.java:40: cannot find symbol
symbol : variable Gtk
location: class com.zetcode.GSimple
Gtk.init(args);
^
Gsimple.java:42: cannot find symbol
symbol : variable Gtk
location: class com.zetcode.GSimple
Gtk.main();
^
14 errors

I have Xubuntu 9.10 and I installed the libjava-gnome-java package.
which more dependencies I need?

By: stu

stu — Fri, 20 Nov 2009 14:17:45 +0000

Cool, so python-antlr fixed it ?

If your having trouble compiling GSimple.java it could be a problem with java-gnome, post the errors here if it’s not working.

I should probably update the article to python 2.6 at some point.

By: Oscar

Oscar — Fri, 20 Nov 2009 13:58:35 +0000

Oops I forgot that, maybe the ‘python-antlr’ package found in synaptic fix my problem.

Pd: sorry for my bad english (just in case)

By: Oscar

Oscar — Fri, 20 Nov 2009 13:55:51 +0000

Hi again, this was helpful, I’m trying to convert java regex into python re, just for a homework, but this is a good tool, I’d do the example but when I type this command ‘$ javac GSimple.java’ show a lot of compilation bugs. In some aplications the .py file shows and and exception with character ‘@’, maybe cannot handle actions commands with interface like ‘@Action’.

Well i’ll show what I’d do for installation:

1. $ sudo apt-get install antlr python2.5 sun-java6-bin libjava-gnome-java
2. $ sudo easy_install-2.5 java2python Don’t work at the beggining but I tried with:
$ sudo apt-get install python-setuptools and again with 2.
3. But the command $ j2py -i don’t work, and then run $ antlr, the system show me try with ‘apt-get install pccts’ I’d do and try again with j2py -i, but nothing.
4. $ sudo synaptic, then search and check all antlr 2.7.7 related packages and then all works without problems.

By: stu

stu — Wed, 18 Nov 2009 14:20:04 +0000

Cool, I thought I was the only one crazy to try this

Keep us posted if you do anything with gtk and jython !

By: Oscar

Oscar — Wed, 18 Nov 2009 13:46:05 +0000

Well, problem solved, it’s maybe a conflict with python 2.6.x and 2.5.x,
I installed antlr 2.7.x from synaptic and all is done.

By: Oscar

Oscar — Wed, 18 Nov 2009 13:25:48 +0000

Hi,
After follow all steps with succes, I have a problem at the moment to execute this command
$ j2py -i
I get this:
Traceback (most recent call last):
File “/usr/local/bin/j2py”, line 9, in
from java2python.lib.lexer import Lexer
File “/usr/local/lib/python2.6/dist-packages/java2python/lib/lexer.py”, line 4, in
import antlr
ImportError: No module named antlr
I have antlr installed, so what else can I do?
Thanks for help.