Python call Java causes Error: Could not find or load main class

Question

I am having issues to use the java program https://github.com/antonydeepak/ResumeParser/ in Django project in a localserver in MAC OS.

I have installed ResumeParser in the Django Project like:

-- Django Project -- app1 -- app2 -- ResumerParser

Here is my code but it says "Could not find or load main class".

if form.is_valid():
 f = form.save(commit=False)
 resume = form.cleaned_data['resume']
 cmd = ['java', '-cp', 'bin/:../GATEFiles/lib/:../GATEFiles/bin/gate.jar:lib/*', 'code4goal.antony.resumeparser.ResumeParserProgram %s textOutput.json' % resume]
 subprocess.Popen(cmd)

Any clues of how to solve this? I've tried every post related to this theme in StackOverflow no success.

Thanks in advance

Answer 1

You're mixing up well-delimiter parameters with parameters grouped with spaces.

cmd = ['java', '-cp', 'bin/:../GATEFiles/lib/:../GATEFiles/bin/gate.jar:lib/*', 'code4goal.antony.resumeparser.ResumeParserProgram %s textOutput.json' % resume]

Your last parameter is seen as a single parameter and is protected by spaces by subprocess:

"code4goal.antony.resumeparser.ResumeParserProgram resume_value textOutput.json"

=> The whole "class<space>param1<space>param2" is seen as your class: no wonder why it's not found.

Split all your parameters and it will work, subprocess won't group your parameters, no quoting (note the forced conversion of the resume object to str):

cmd = ['java', '-cp', 'bin/:../GATEFiles/lib/:../GATEFiles/bin/gate.jar:lib/*', 'code4goal.antony.resumeparser.ResumeParserProgram', str(resume),'textOutput.json']

• Ronaldo Bahia: Thanks for the fast answer. Now I have a new error: execv() arg 2 must contain only strings
• Jean-François Fabre: sorry! the resume object needed to be converted to a string, see my edit.

Answer 2

After two weeks I got it working. All files must be copied to the ResumeParser/ResumeTransducer dir.

Also, there's a need to inform the current dir for file parsing.

Here is the implementation:

# first save the file
if form.is_valid():
 f = form.save(commit=False)
 resume = form.cleaned_data['resume']
 f.resume = resume
 f.save()
 # copy file to the CV parser dir so java can parse the file
 cf = "." + f.resume.url
 shutil.copy2(cf, 'ResumeParser/ResumeTransducer')
 # get file to convert
 fl_name = str(f.resume).split('/')[-1]
 # get file name to make json output
 base_name = os.path.splitext(fl_name)[0]
 cmd = "java -cp 'bin/*:../GATEFiles/lib/*:../GATEFiles/bin/gate.jar:lib/*' code4goal.antony.resumeparser.ResumeParserProgram %s %s.json" % (fl_name, base_name)
 # get the current working dir 
 os.chdir("ResumeParser/ResumeTransducer")
 # call java
 subprocess.Popen(cmd, shell=True)

Thanks Jean-François Fabre!