Allow jdtls.py to be dynamically imported

[Trenek]

Previous jdtls script didn't import jdtls.py properly, this is a problem I happened to have.

The proposed change solves this problem entirely by importing jdtls.py module dynamically

[eclipse-ls-bot]

Can one of the admins verify this patch?

[rgrunber]

Would you be able to set PYTHONPATH in your shell to point to the directory that contains jdtls.py. After that you would be able to run jdtls wherever you place it, without the need to dynamically import the module in the script.

[Trenek]

Just checked it out and apparently addition of PYTHONPATH doesn't change a thing

Even if there are some other fixes, wouldn't a change to a script in order to make it more user-friendly (and especially java-dev-with-no-knowledge-about-python-friendly), this way or the other, be beneficial in the long run? 🤔

[rgrunber]

Ok, had to ask since even https://docs.python.org/3/library/importlib.html#importing-a-source-file-directly mentions this approach should be a last resort.

[rgrunber]

I keep forgetting this becomes an issue for contributors outside Eclipse, but would you be able to sign the ECA : https://www.eclipse.org/legal/eca/ ? If you really can't I can try double checking if there's any criteria where I can bypass, but I'm pretty sure it needs to be signed.

[Trenek]

Oh, sure, I actually already did, but by clicking commit on github it automatically gave my other e-mail lol

[Trenek]

ok, I did change the commit author to my other email, now everything seems fine ^^

[rgrunber]

Thanks for taking the time to do this!

[rgrunber]

@Trenek out of curiosity, would you be able to share how you were setting up JDT-LS in order to run into this issue. Were jdtls.py and jdtls really kept in the same folder ? Where did you download it from ? The part that's confusing me is, this fix basically just dynamically loads jdt.ls.py from the same directory as the jdtls script. But this should already have worked without the change, since the script's directory should be on python's module path.

For example, if I just create a simple python script to output the module path :

$ cat test.py 
#! /usr/bin/python
import sys
print(sys.path)

executing it from any location, will always include the script's directory on the module path :

$ /tmp/foo/test.py 
['/tmp/foo', '/usr/lib64/python313.zip', '/usr/lib64/python3.13', '/usr/lib64/python3.13/lib-dynload', '/usr/lib64/python3.13/site-packages', '/usr/lib/python3.13/site-packages']

[Trenek]

I downloaded jdtls from here, jdt-language-server-latest.tar.gz on a pretty much fresh Windows 10 installation and then downloaded python-3.13.2-embed-amd64.zip
After downloading python and jdtls I just unzipped those and created an environment variables