Add java support via jdtls.

[PerilousBooklet]

This PR is incomplete, as it lacks the bundled jdk.

[PerilousBooklet]

How should we approach the bundling of the jdk? Do we download the jre only or the jdk? Also, from what I found it seems that lpm could just download the jdk files into a subfolder of USERDATA/plugins/lsp_java and then we change the command path in the plugin's init.lua. Am I missing something?

[adamharrison]

Hrm. I'd say minimum required to run. So, if that's just the JRE; then I'd say just use that. Maybe even flag it as optional; as many people who're devleoping java will have a system-wide JRE anyway.

[Guldoman]

Ideally it shouldn't be bound to lsp_java as it could be used for other things. So yeah, an optional dependency to a java_jre library sounds ideal.

[PerilousBooklet]

The xml lsp lemminx would also need it.

[adamharrison]

lpm will cache downloads, so not a huge deal to have both, really. If it makes it simpler.

[PerilousBooklet]

Should I add something like this:

{
  "id": "jdk",
    "description": "Production and Early-Access OpenJDK Builds, from Oracle.",
    "version": "21.0.2",
    "type": "library",
    "mod_version": "3",
    "files": [
      {
        "url": "https://download.java.net/java/GA/jdk21.0.2/f2283984656d49d69e91c558476027ac/13/GPL/openjdk-21.0.2_linux-x64_bin.tar.gz",
        "arch": ["x86_64-linux"],
        "checksum": ""
      },
      {
        "url": "https://download.java.net/java/GA/jdk21.0.2/f2283984656d49d69e91c558476027ac/13/GPL/openjdk-21.0.2_macos-aarch64_bin.tar.gz",
        "arch": ["aarch64-darwin"],
        "checksum": ""
      },
      {
        "url": "https://download.java.net/java/GA/jdk21.0.2/f2283984656d49d69e91c558476027ac/13/GPL/openjdk-21.0.2_macos-x64_bin.tar.gz",
        "arch": ["x86_64-darwin"],
        "checksum": ""
      },
      {
        "url": "https://download.java.net/java/GA/jdk21.0.2/f2283984656d49d69e91c558476027ac/13/GPL/openjdk-21.0.2_windows-x64_bin.zip",
        "arch": ["x86_64-windows"],
        "checksum": ""
      }
    ]
}

to make lpm download all the jdk versions needed?

[PerilousBooklet]

This is going to be my first solution to a conflict, so I'd rather ask to be sure: what I think I should do is the following:

git checkout java
git rebase master
git checkout master
git merge java

Am I missing something?

[PerilousBooklet]

Currently there are two problems:

• [x] there's a problem with escaped characters in the Windows jdk path check
• [x] lpm downloads the entire repo inside of USERDIR/libraries/jdk/

[PerilousBooklet]

I'm fine with it.

[PerilousBooklet]

Ok, the current problems are:

• [x] lpm downloads the entire lite-xl-lsp-servers repo inside of the USERDIR/libraries/jdk
• [x] the lsp plugin says that jdtls is registered but not installed

[PerilousBooklet]

I should be able to tell lpm to put the extracted jdk archive inside USERDIR/libraries/jdk, but at the moment I'm not sure if it's possible.

[Guldoman]

The current version of the lsp plugin doesn't support setting env variables, so this is trying to execute an executable named JAVA_HOME=.... See lite-xl/lite-xl-lsp#84.

For now you could try wrapping the command in a shell, so { "bash", "-c", "JAVA_HOME=... jdk..." }.

[PerilousBooklet]

I think the only problem remaining is finding the right command syntax to run jdtls.

[PerilousBooklet]

The last thing remaining is writing the java_command for Windows.

[Guldoman]

Looks like this is broken on Windows because of lite-xl/lite-xl-plugin-manager#74.

[Guldoman]

Is this still trying to execute the python script? This should not depend on the user having python installed and working, so we should run jdtls directly using java.

[PerilousBooklet]

It's still using the script I think.

[Guldoman]

Btw lite-xl/lite-xl-lsp#97 adds env support to the LSP plugin. If you try using it, let me know how it goes.

[PerilousBooklet]

I'll try right away. Who needs to sleep anyway.

[PerilousBooklet]

Seems to be working.

[Guldoman]

Awesome! Thanks for testing!

[PerilousBooklet]

Now we have to wait until the env var PR is merged in lsp. And the windows command check.

[Guldoman]

And to avoid using the python script.

[PerilousBooklet]

I think we're ready to merge.

[Guldoman]

Thank you!