JDTLS spawns separate process per module in Java Maven multi-module projects

[areyouok]

Description

In a Maven multi-module project (parent pom.xml with <modules>), JDTLS spawns a separate process for each submodule instead of sharing a single instance at the topmost parent pom.xml.

For example, with this structure:

project-root/
  pom.xml              (parent, declares <modules>)
  module-a/pom.xml     (child module)
  module-b/pom.xml     (child module)

Opening Java files in module-a and module-b each starts a separate JDTLS process. Each JDTLS instance uses ~1GB, so a project with 5+ modules easily consumes 5GB+ of memory.

The existing fix (#14192) resolved this for Gradle monorepos by walking up to find settings.gradle. However, Maven multi-module projects were not addressed — the root detection still falls back to the nearest pom.xml for Maven projects.

Steps to reproduce

1. Create a Maven multi-module project with a parent pom.xml and 3+ child modules
2. Open Java files from different modules in opencode
3. Observe multiple JDTLS processes via ps aux | grep jdtls

Operating System

macOS 26.4 (aarch64)

[github-actions]

This issue might be a duplicate of (or closely related to) an existing issue. Please check:

• JDTLS spawns redundant per-module processes in Java monorepos, causing OOM #11368: JDTLS spawns redundant per-module processes in Java monorepos, causing OOM — same root cause and symptom; the fix there targeted Gradle multi-module projects. If JDTLS spawns redundant per-module processes in Java monorepos, causing OOM #11368's fix did not extend to Maven projects, this issue may be a follow-up rather than a full duplicate.

[areyouok]

#11368 is not exactly the same as this issue. It's already closed, but the Java Maven multi-module scenario was not fixed. opencode spawns numerous JDTLS processes, making LSP nearly unusable for Java projects. The PR I submitted fixes this issue.

[scrumpypoker]

Confirmed, the Maven multi-module issue is still there. This screenshot can help you realise what the multi-module Maven situation with OpenCode is :-) Fixing this issue will really help a lot with development process for more complex repositories and will free gigabytes of RAM.

[areyouok]

@scrumpypoker You can use my PR and build it yourself. I’ve been using it for days.