PythonInterpreter exec function return empty output stream

Question

I'm using org.python.util.PythonInterpreter class to execute python code in java. Please find below the snippet of of my code.

PythonInterpreter pythonInterpreter = new PythonInterpreter(null, new PySystemState());

ByteArrayOutputStream outStream = new ByteArrayOutputStream(16384);

pythonInterpreter.setOut(outStream);
pythonInterpreter.setErr(outStream);

// execute the code
pythonInterpreter.exec(script);

String consoleOutput = outStream.toString();
outStream.flush();

System.out.println("Console output :- "+consoleOutput);

The problem with the above code is for the same script sometimes I get 'consoleOutput' empty. I'm not able to figure out the problem. For running the above code 1000 times, at least 4 times I get empty output.

On the other hand if I use the default constructor as shown below it works just fine

PythonInterpreter pythonInterpreter = new PythonInterpreter();

Answer 1

Digging more into the problem I found, setting the property python.site.import to false triggers this problem. This issue occurs in Jython standalone version 2.7.0. Updating to the June 2017 release of the standalone jar(2.7.1) fixes this issue.