Java LSP (Eclipse JDT.LS)

This plugin brings Eclipse JDT Language Server into Claude Code and runs the same analyzer used by Eclipse and VS Code. It reads your Java classpath, parses source and compiled jars, and reports syntax and type errors as you edit. You get hover Javadoc, parameter hints, and signature help that pull straight from your project's sources and dependencies.

It sends and receives LSP requests for completion, goto-definition, find-references, workspace-symbols, and call-hierarchy. You can run refactor actions like rename, extract method, and move type; apply quick fixes such as adding imports or converting between stream and loop forms; and run organize imports and format actions against your codebase.

The server watches project files, reads Maven/Gradle metadata, and updates the workspace classpath so diagnostics stay accurate after dependency or module changes. It also provides launch configuration suggestions and links to problem markers so you can jump from an error to the offending code, apply a fix, and re-run a build without leaving the editor.

For example, when you open a large monorepo and need to rename a public class used across multiple modules, the plugin finds all references, applies the rename across files, updates imports, and runs quick diagnostics — avoiding the need to switch to Eclipse or a separate IDE to perform safe refactors and validation.