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Problems with manual installation of `jdtls`

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#421 6 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
emacs-lisp, java, nixos
Domain
developer-experience, tooling

Research direction

No source file or test is named in the report. Start with the manual-installation path controlled by lsp-java-server-install-dir, then trace how the launcher handles the read-only Nix store and resolves the jdtls executable. Done means the reported manual jdt-language-server setup works without writing to the Nix Store and its executable naming is addressed.

Written by the indexing model from the issue text.

Description

This is not really a bug, more of a question.

I am trying to use lsp-java with a manual installation of jdtls. I use NixOS, and provide the language server, which is called jdt-language-server in Nixpkgs, in the environment. I also set lsp-java-server-install-dir to point to the correct directory. However, lsp-java fails to run because the installation directory of jdt-language-server is in the Nix Store, and therefore read-only, which leads to several errors. For example,

!STACK
java.nio.file.FileSystemException: /nix/store/4qvyvcbn6h1sm8dvx9wjrv3y5az1znp2-jdt-language-server-1.19.0/share/java/config_linux: Read-only file system
	at java.base/sun.nio.fs.UnixException.translateToIOException(UnixException.java:100)
	at java.base/sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:106)
	at java.base/sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:111)
	at java.base/sun.nio.fs.UnixFileSystemProvider.createDirectory(UnixFileSystemProvider.java:397)
	at java.base/java.nio.file.Files.createDirectory(Files.java:700)
	at java.base/java.nio.file.Files.createAndCheckIsDirectory(Files.java:807)
	at java.base/java.nio.file.Files.createDirectories(Files.java:793)
	at org.eclipse.equinox.launcher.Main.extractFromJAR(Main.java:2313)
	at org.eclipse.equinox.launcher.Main.getLibraryFromFragment(Main.java:535)
	at org.eclipse.equinox.launcher.Main.getLibraryPath(Main.java:495)
	at org.eclipse.equinox.launcher.Main.setupJNI(Main.java:448)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:579)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1467)
	at org.eclipse.equinox.launcher.Main.main(Main.java:1440)

Further, I read somehwere that the language server executable name jdtls is hardcoded into lsp-java. Is this so? (NixOS uses jdt-language-server).

I should note that everything works fine when using the jdtls installation method provided by lsp-java.

Dominant language
Emacs Lisp
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Forks
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