jdtls: pom.xml validation failure blocks file indexing; need explicit source path configuration

[zhanpengliu-tencent]

Problem

When using jdtls to analyze Java projects, if pom.xml validation fails (e.g., "Non-resolvable parent POM"), jdtls fails to index the project's Java files. Basic operations like textDocument/documentSymbol stop working for files in the project.

This is common when analyzing arbitrary third-party projects where parent POMs are hosted on private/inaccessible registries.

Current workarounds and their limitations

1. Lightweight/syntax mode (-Dsyntaxserver=true): Disables textDocument/references and other semantic features — not usable for reference finding.

2. Disable Maven/Gradle import (java.import.maven.enabled: false): jdtls loses awareness of the multi-module project structure, so cross-module references don't work.

None of these options provide best-effort cross-module reference finding without requiring successful dependency resolution.

Proposed solution

Extract module structure directly from pom.xml / settings.gradle without invoking Maven/Gradle, then configure jdtls with explicit source paths:

• Parse <modules> from pom.xml (Maven) or include from settings.gradle (Gradle)
• Map each module to its conventional source directory (e.g., {module}/src/main/java)
• Pass discovered paths via java.project.sourcePaths in initializationOptions
• Disable Maven/Gradle import to avoid resolution errors

This gives jdtls full visibility into all source files across modules, enabling cross-module reference finding without any dependency resolution.