On Thu, 4 Jul 2013, Johan Jonkers wrote:
I've tried added the Sum class to the 2nd JCC call but it didn't solve the
problem. The 'asSum' method isn't getting wrapped. Also, instantiating a
SumWrapper with a Sum as argument results in the constructor without
parameters being called; which I wasn't expecting.
c=SumWrapper(Sum(10))
Empty constructor
I tried compiling everything into one file and then I do get the asSum method
wrapped but the constructor with a Sum as argument doesn't seem to work
still. It doesn't call the empty constructor anymore but neither does it seem
to set Sum object passed to it. I am a bit at a loss here on whats going
wrong (or what I am doing wrong).
Yeah, let's take one thing at a time and the simpler one first.
Compiling all into one module, I was not able to reproduce the problem as
reported. I'm able to make a SumWrapper(Sum(10)) just fine.
Here are the commands I used to try to reproduce this:
- created two class files Sum.java and SumWrapper.java in their respective
packages as specified in your example
- mkdir classes
- javac -d classes *.java
- jar -cvf sum.jar -C classes .
- python -m jcc.__main__ --shared --arch x86_64 --use_full_names --jar
sum.jar --classpath . --python sum --build --install
- python
- import sum
- sum.initVM()
<jcc.JCCEnv object at 0x10029c0f0>
- from nl.seecr.freestyle import Sum
- from org.cq2.freestyle import SumWrapper
- Sum(10)
<Sum: nl.seecr.freestyle.Sum@64fef26a>
- SumWrapper(Sum(10))
<SumWrapper: org.cq2.freestyle.SumWrapper@70e69696>
Please try to reproduce these steps and report back.
Once that works, let's move on to the problem of compiling these into
separate extension modules.
Andi..
Any thoughts on this problem would be appreciated :-)
Regards,
Johan
On 7/1/13 8:00 PM, Andi Vajda wrote:
On Mon, 1 Jul 2013, Johan Jonkers wrote:
Hello,
I have been playing around with JCC to see if it would provide in the
needs we have here at work to interface Java with Python. I have
encountered one issue in which I hope someone on this mailinglist might be
able to help me with. If this is not the right place to ask then I
apologize in advance.
This issue I am having is that I would like to create two packages
compiled with JCC in which classes from one package are used by classes in
the other pacakge. I would like to use those classes in Python but am
having problems doing so that I don't understand yet.
In package 1 is the class shown below:
package nl.seecr.freestyle;
public class Sum {
private int _sum;
public Sum() {
_sum = 0;
}
public void add(int value) {
_sum += value;
}
public int value() {
return _sum;
}
}
The second package holds a class what uses the Sum Class:
package org.cq2.freestyle;
import nl.seecr.freestyle.Sum;
public class SumWrapper {
private Sum total;
public SumWrapper() {
this(new Sum());
System.out.println("Empty constructor");
}
public SumWrapper(Sum sum) {
total = sum;
}
public void add(int value) {
total.add(value);
}
public int value() {
return total.value();
}
public Sum asSum() {
Sum sum = new Sum();
sum.add(value());
return sum;
}
public void printValue() {
System.out.println(value());
}
}
I can compile these classes into .class files and put them in jars and
have those compiled with JCC:
python -m jcc \
--root ${ROOT} \
--use_full_names \
--shared \
--arch x86_64 \
--jar cq2.jar \
--classpath ./seecr.jar \
--python cq2 \
--build \
--install
export PYTHON_PATH=${ROOT}/usr/local/lib/python2.7/dist-packages
python -m jcc \
--root ${ROOT} \
--use_full_names \
--import cq2 \
--shared \
--arch x86_64 \
--jar seecr.jar \
--python seecr \
--build \
--install
In my understanding the "--import cq2" argument should prevent jcc from
creating a wrapper for the Sum class in the seecr package itself but use
the one in the cq2 package.
This all compiles without errors but when I run the following python
program:
import seecr
seecr.initVM()
import cq2
cq2.initVM()
from nl.seecr.freestyle import Sum
from org.cq2.freestyle import SumWrapper
sum = Sum()
sum.add(5)
print "Sum value", sum.value()
wrapper = SumWrapper(sum)
print wrapper.value()
The 1st print shows the value 5 as expected. The 2nd print however shows 0
and I had not expected that. If I run the same program in Java and use the
jars I created earlier, the 2nd print shows 5 (as expected). The "Empty
constructor" message is also shown when running this python program and I
had not expected that to happen.
The "asSum" method in the SumWrapper class is not available in the Python
version of the class. I do not understand yet why that is.
I haven't been able to find many examples or documentation on the options
for compiling with JCC. I am hoping that someone here on the mailinglist
can point me in the right direction. Any help would be really appreciated.
I haven't had time yet to reproduce the problem but you may want to try to
add an explicit request to wrap the Sum class - by just listing it on the
second jcc call command line. No wrapper will be generated for it, because
of the --import statement, but methods in the second jar with Sum in their
signature should then get wrapped.
python -m jcc \
--root ${ROOT} \
--use_full_names \
--import cq2 \
--shared \
--arch x86_64 \
--jar seecr.jar \
--python seecr \
--build \
--install \
nl.seecr.freestyle.Sum
Andi..
--
Johan Jonkers ? seecr.nl ? +31 (0) 655 734 175
