Java LSP (jdtls) not working in version 1.3.13 (regression)

[swpuchenxinde]

Description

Java LSP (jdtls) is not functioning in opencode v1.3.13. When opening Java files with syntax errors, the LSP does not detect or highlight these errors. No real-time error checking, auto-completion, or other LSP features are working. This worked correctly in previous versions of opencode.

Tested Java versions:

• Java 26 (current) ✓
• Java 21 ✓

Both Java versions have the same issue - LSP (jdtls) is not working.

Plugins

No response

OpenCode version

1.3.13

Steps to reproduce

1. Install opencode v1.3.13
2. Open a Java project
3. Open any Java file with syntax errors
4. Observe that no errors are highlighted or detected by LSP
5. Try auto-completion and other LSP features - they don't work

Note: The same files work correctly with LSP in previous opencode versions.

Screenshot and/or share link

No response

Operating System

Windows

Terminal

No response

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• Java LSP (jdtls) not working in version 1.3.13 (regression) #20451: Same title, same author, same content — "Java LSP (jdtls) not working in version 1.3.13 (regression)" — this issue appears to be a resubmission of the recently closed Java LSP (jdtls) not working in version 1.3.13 (regression) #20451.

If this is intentional (e.g., the previous issue was closed incorrectly), please clarify in a comment. Otherwise, consider continuing the discussion in the original issue.

[sparra-inmoba]

I had the same issue and met the requirements (Java version 21 or higher). When I enabled debug logging, I noticed that the server wasn't detecting the correct Java version. After checking the code, I found this line:

opencode/packages/opencode/src/lsp/server.ts

Line 1102 in 9b6db08

const m = /"(\d+)\.\d+\.\d+"/.exec(result.stderr.toString())

It seems the LSP expects the Java version to have three digits, but my installed Java only displayed one, e.g. openjdk "21" .... I updated to the latest version, which now reports three digits openjdk "21.0.10" 2026-01-20 LTS, and after that the LSP started working correctly in OpenCode.

[Hona]

haha nice thats the stderr debug logging I just added yesterday! @sparra-inmoba :)

I'll see if I can repro and fix this for ya

[nagarciah-mms]

FYI, fails as well in linux with this output of java -version:

openjdk version "25.0.3-ea" 2026-04-21
OpenJDK Runtime Environment (build 25.0.3-ea+7-Ubuntu-2)
OpenJDK 64-Bit Server VM (build 25.0.3-ea+7-Ubuntu-2, mixed mode, sharing)

BTW, opencode version is 1.14.33