Lazarus

A semantic code analysis and reporting plugin for IntelliJ IDEA that generates intelligent insights about your Java/Kotlin codebase using graph-based analysis and LLM-powered semantic understanding.

Goal: optimize token consumption

Overview

Lazarus is an IntelliJ IDEA plugin that builds and maintains a semantic graph of your codebase, analyzing relationships between files, classes, methods, and variables. It leverages LLM agents to generate contextual reports about code structure, dependencies, and changes, making it easier to understand complex codebases and track semantic impacts of modifications.

Key Features

• Semantic Code Graph: Automatically builds a comprehensive graph representation of your codebase, capturing:
  • File → Class → Method → Variable hierarchies
  • Method call relationships
  • Field access patterns
  • Class inheritance structures

• Intelligent Reporting: Three types of semantic reports:

  • File Semantic Report (Ctrl+Alt+S): Analyze a single file and its connections
  • Global Semantic Report (Ctrl+Alt+Shift+S): Generate a project-wide semantic analysis
  • Git Diff Semantic Report (Ctrl+Alt+Shift+D): Fetch remote changes and analyze their semantic impact

• Git Integration: Seamlessly tracks and analyzes changes across branches with semantic diff capabilities

• LLM-Powered Analysis: Integrates with external LLM services to generate human-readable insights about code structure and changes

Architecture

Core Components

1. Graph Building (PsiGraphBuilder)

   • Uses IntelliJ's PSI (Program Structure Interface) to parse source code
   • Builds an indexed code graph with nodes (files, classes, methods, variables) and edges (relationships)
   • Automatically initializes on project load and maintains incremental updates

2. Graph Storage (SemGraphStorage)

   • Persists the semantic graph to disk in the .lazarus directory
   • Supports efficient loading and saving of graph state

3. Graph Analysis (SemGraphAnalysis)

   • Analyzes graph structure to identify connected components
   • Traces relationships and generates connection descriptions
   • Supports both file-level and project-wide analysis

4. LLM Agent Service (LLMAgentService)

   • Communicates with external LLM API for semantic report generation
   • Formats graph analysis data with file contents for LLM processing
   • Supports incremental and general report types

5. Git Services

   • DiffService: Fetches and processes git diffs
   • CommandRepository: Executes git commands
   • DiffRepository: Manages diff data retrieval

Data Model

Graph Nodes:

• FILE: Source file nodes
• CLASS: Class/interface declarations
• METHOD: Method/function definitions
• VARIABLE: Field declarations

Graph Edges:

• CONTAINS: Hierarchical containment (file → class, class → method)
• CALLS: Method invocation relationships
• ACCESSES: Field access patterns
• INHERITS: Class inheritance relationships

Installation

1. Clone the repository:

git clone <repository-url>
cd Lazarus

2. Build the plugin:

cd lazarus-plugin
./gradlew buildPlugin

3. Install in IntelliJ IDEA:
   • Go to Settings → Plugins → ⚙️ → Install Plugin from Disk
   • Select the built plugin from lazarus-plugin/build/distributions/

Configuration

The plugin requires an external LLM service running. Configure the endpoint in HttpClient.kt (default: http://localhost:8000).

Usage

Quick Start

1. Open a Java/Kotlin project in IntelliJ IDEA
2. The plugin automatically builds the semantic graph on project load
3. Use keyboard shortcuts or toolbar actions to generate reports:

Actions

Action	Shortcut	Description
Generate Semantic Report	Ctrl+Alt+S	Analyze the currently open file
Global Semantic Report	Ctrl+Alt+Shift+S	Analyze entire project
Fetch-Compare Semantics	Ctrl+Alt+Shift+D	Fetch remote changes and show semantic diff

Example Workflow

1. Analyze a file: Right-click in editor → "Generate Semantic Report"
2. View connections: The report shows all related files, methods called, and semantic descriptions
3. Track changes: Before merging, use "Fetch-Compare Semantics" to understand the impact of remote changes

Technical Details

• Language: Kotlin
• Target Platform: IntelliJ IDEA 2025.1.4+
• Build System: Gradle with IntelliJ Platform Plugin
• Dependencies:
  • JGit for Git operations
  • Kotlinx Serialization for JSON handling
  • SLF4J/Logback for logging

Project Structure

Lazarus/
├── .lazarus/                    # Graph storage directory
└── lazarus-plugin/
    ├── src/main/kotlin/org/example/lazarusplugin/
    │   ├── Main.kt             # Plugin startup
    │   ├── actions/            # UI actions (reports, toolbar buttons)
    │   ├── models/             # Data models (graph, git)
    │   ├── repository/         # Git command/diff repositories
    │   ├── services/
    │   │   ├── git/           # Git integration services
    │   │   └── graph/         # Graph building, storage, analysis
    │   ├── ui/                # Report display dialogs
    │   └── utils/             # HTTP client, file utilities
    └── src/main/resources/
        └── META-INF/plugin.xml

Development

Requirements

• JDK 21
• Gradle 8.x
• IntelliJ IDEA 2025.1.4+

Building

./gradlew build

Testing

./gradlew test

Running in Development

./gradlew runIde

Limitations

• Currently supports Java and Kotlin files only
• Requires external LLM service for report generation
• Graph building may take time on large projects

Contributing

Contributions are welcome! Please ensure:

• Code follows Kotlin conventions
• Tests are included for new features
• Plugin compatibility is maintained

License

MIT Licencse

Authors

EjAj

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Note: This plugin is under active development. Features and APIs may change.