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jdtls-server will not start.

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#426 13 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
Domain
developer-experience, tooling

Research direction

Start with the lsp-java--ls-command value and the Java paths in the issue, then compare the manually executed command with the Messages and stderr buffers. The issue is resolved when lsp-java starts jdtls successfully and no longer reports exit code 13.

Written by the indexing model from the issue text.

Description

This problem seems closely related to #293.

When trying to start the lsp-java server, I receive the message

Server jdtls:27072/starting exited with status exit(check corresponding stderr buffer for detail). Do you want to restart it? (y or n)

When looking in the Messages buffer, I read

using config for config_linux
LSP :: Connected to [jdtls:34071/starting].
When done with a buffer, type C-x #
LSP :: jdtls has exited (exited abnormally with code 13)
Server jdtls:34071/starting exited with status exit(check corresponding stderr buffer for details). Do you want to restart it? (y or n) y

The stderr buffer reads

Process jdtls stderr finished

M-: lsp-java--ls-command results in

("/usr/lib/jvm/java-19-openjdk/bin/java" "-Declipse.application=org.eclipse.jdt.ls.core.id1" "-Dosgi.bundles.defaultStartLevel=4" "-Declipse.product=org.eclipse.jdt.ls.core.product" "-Dlog.protocol=true" "-Dlog.level=ALL" "-XX:+UseParallelGC" "-XX:GCTimeRatio=4" "-XX:AdaptiveSizePolicyWeight=90" "-Dsun.zip.disableMemoryMapping=true" "-Xmx1G" "-Xms100m" "-jar" "/home/user-name/.emacs.d/.cache/lsp/eclipse.jdt.ls/plugins/org.eclipse.equinox.launcher_1.6.400.v20210924-0641.jar" "-configuration" "/home/user-name/.emacs.d/.cache/lsp/eclipse.jdt.ls/config_linux" "-data" "/home/user-name/.emacs.d/workspace/" "--add-modules=ALL-SYSTEM" "--add-opens java.base/java.util=ALL-UNNAMED" "--add-opens java.base/java.lang=ALL-UNNAMED")

Manually executing the code gives

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Content-Length: 122

{"jsonrpc":"2.0","method":"window/logMessage","params":{"type":3,"message":"26.03.2023, 13:55:15 Main thread is waiting"}}

I have multiple versions of Java installed, but the current version (found out by which java) is java-19-openjdk. I am using the code below to setup my Emacs for lsp-java.

  (use-package lsp-java
  :ensure t
  :config
  (add-hook 'java-mode-hook 'lsp)
  (setq lsp-java-completion-max-results 10)
  (setenv "JAVA_HOME"  "/usr/lib/jvm/java-19-openjdk/")
  (setq lsp-java-inhibit-message nil)
  (setq lsp-java-save-actions-organize-imports t)
  (setq lsp-java-java-path "/usr/lib/jvm/java-19-openjdk/bin/java")
  (setq lsp-java-configuration-runtimes '[(:name "JavaSE-19"
                                                 :path "/usr/lib/jvm/java-19-openjdk/"
                                                 :default t)]))

(use-package dap-mode
  :ensure t
  :after lsp-mode
  :config (dap-auto-configure-mode))

(use-package dap-java :ensure nil)

As you can see, I am already trying to make every path explicit. What I have also tried is …

  1. deleting the path of lsp-java-workspace-dir.
  2. Reinstalling the jdtls server.

What could be the problem?

Dominant language
Emacs Lisp
Stars
696
Forks
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No merged PRs in 30d

Getting set up

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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