Run a Java main class using its relative path? (Python)

Question

I am using Python to execute the JVM for a specified Java class, like so:

import subprocess
output = subprocess.check_output("java MyJavaClass")

However, the Java class is not in the same directory as the Python script, so this does not work. It is in a bin directory two directories up.

So I was hoping it would be possible to do something like below, but it doesn't work:

output = subprocess.check_output("java ../../bin/MyJavaClass")

Any ideas?

• Thomas K: What is the working directory when that Python code runs? os.getcwd()

Answer 1

You need to set the classpath, like this:

java -classpath ../../bin MyJavaClass

Please note, that if your class belongs to a certain package, you have to use the FQN (Full Qualified Name):

java -classpath ../../bin my.package.MyJavaClass

Answer 2

Try

output = subprocess.check_output("java MyJavaClass", cwd="../../bin/")

When running Java, the directory structure implies a package structure, so it is required to execute java from the correct directory (unless using classpath).

• XåpplI'-I0llwlg'I -: Accepted this answer since it keeps the "directory changing" in Python. Both good answers though.