JIAP - Java Intelligence Analysis Platform

A comprehensive platform for Java bytecode analysis and Android application reverse engineering, integrating JADX decompiler with AI assistant capabilities through MCP (Model Context Protocol).

Installation

Prerequisites

Java 17+ for JIAP Core
Python 3.10+ for MCP Server (optional - auto-managed)
JADX decompiler with plugin support (v1.5.2+)
Python dependencies: requests, fastmcp, pydantic

Build from Source

# Build JIAP Core
cd jiap
chmod +x gradlew
./gradlew dist

# The MCP server is bundled and auto-managed by the plugin
# No manual Python dependency installation required

Usage

1. Install and Start JIAP Plugin

# JADX Command Line 
jadx plugins --install-jar <path-to-jiap.jar>

# JADX GUI 
# JADX -> Settings -> Plugins -> Enable JIAP

Companion Process Mechanism:

When JIAP plugin starts, it automatically launches the MCP server as a companion process
The MCP server runs as a sidecar process managed by the plugin
No manual MCP server startup required
The companion process automatically stops when JIAP plugin unloads or JADX exits

What happens automatically:

JIAP plugin starts HTTP server on port 25419
Plugin extracts MCP scripts to ~/.jiap/mcp/
Companion process (MCP server) starts on port 25420
Plugin monitors companion process health
Both processes stop together on shutdown

2. Verify Connection

Use health_check() to verify the connection between MCP server and JIAP plugin.

3. Available Tools

All tools support pagination via the page parameter.

Code Analysis

get_all_classes(page=1) - Retrieve all available classes
search_class_key(key, page=1) - Search for classes by keyword in source code (case-insensitive)
get_class_source(class_name, smali=False, page=1) - Get class source code in Java or Smali format
search_method(method_name, page=1) - Search for methods matching the name
get_method_source(method_name, smali=False, page=1) - Get method source code using full signature
get_class_info(class_name, page=1) - Get class information (fields and methods)
get_method_xref(method_name, page=1) - Find method usage locations
get_field_xref(field_name, page=1) - Find field usage locations
get_class_xref(class_name, page=1) - Find class usage locations
get_implement(interface_name, page=1) - Get interface implementations
get_sub_classes(class_name, page=1) - Get subclasses

UI Integration

selected_text(page=1) - Get currently selected text in JADX GUI
selected_class(page=1) - Get currently selected class in JADX GUI

Android Analysis

get_app_manifest(page=1) - Get Android manifest content
get_main_activity(page=1) - Get main activity source
get_application(page=1) - Get Android application class and information
get_exported_components(page=1) - Get exported components (activities, services, receivers, providers) with permissions
get_deep_links(page=1) - Get app URL schemes and intent filters
get_system_service_impl(interface_name, page=1) - Get system service implementations

Vulnerability Mining

get_dynamic_receivers(page=1) - Get dynamically registered BroadcastReceivers

System

health_check() - Verify server connection status

Configuration

Port Configuration

The JIAP server port can be configured via:

GUI: JIAP Server Status menu → Set new port → Auto-restart
Plugin Options: Set jiap.port in JADX plugin options
Default: 25419 (JIAP), 25420 (MCP companion)

MCP Script Path

If you want to use a custom MCP server script:

GUI: JIAP Server Status menu → Browse and select custom script
Plugin Options: Set jiap.mcp_path to custom script path
Default: Auto-extracted to ~/.jiap/mcp/jiap_mcp_server.py

Companion Process Configuration

The companion process (MCP server) is automatically configured:

# Auto-detected executor: uv, python3, or python
# Auto-extracted scripts to ~/.jiap/mcp/
# Auto-started with correct JIAP_URL and MCP_PORT
# Auto-monitored and restarted if needed

Cache Configuration

JIAP supports two cache modes for improved performance:

disk (default): Persists decompilation cache to disk (~/.jiap/cache/)
memory: Keeps cache in memory only, faster for small projects

Configuration:

Plugin Options: Set jiap.cache to disk or memory
Default: disk for better performance on subsequent runs

Performance Optimization

JIAP includes automatic performance optimizations:

Decompiler Warmup:

When JIAP starts, it automatically warms up the decompiler engine
Filters out SDK packages (android., androidx., java., javax., kotlin.*)
Randomly samples up to 15,000 application classes
Ensures optimal performance for subsequent queries

Disk Caching:

Decompiled code is cached to disk for faster retrieval
Cache persists across JADX sessions
Significantly reduces analysis time for large projects

Error Codes

JIAP uses structured error codes for clear diagnostics:

| Code | Description | Common Cause | |------|-------------|--------------| | E001 | Internal server error | Unexpected server state | | E002 | Port in use | Another service using the port | | E003 | Server start failed | Port binding or initialization error | | E004 | Server stop failed | Graceful shutdown timeout | | E005 | Server restart failed | Restart sequence error | | E006 | JADX unavailable | Decompiler not initialized | | E007 | JADX init failed | Decompiler initialization error | | E008 | Python not found | No Python/uv executable found | | E009 | Sidecar script not found | MCP script extraction failed | | E010 | Sidecar start failed | Companion process failed to start | | E011 | Sidecar process error | Companion process crashed | | E012 | Sidecar stop failed | Companion process won't stop | | E013 | Service error | General service failure | | E014 | Health check failed | Cannot reach JIAP server | | E015 | Method not found | Requested method doesn't exist | | E016 | Missing parameter | Required parameter not provided | | E017 | Invalid parameter | Parameter format/value invalid | | E018 | Unknown endpoint | Requested API endpoint doesn't exist | | E019 | Connection error | Network/HTTP connection failed |

Error Response Format:

{
  "error": "E010",
  "message": "Sidecar start failed: Python executable not found"
}

Architecture

Component Overview

┌─────────────────────────────────────────────────────────┐
│                    JADX GUI                              │
│  ┌─────────────────────────────────────────────────┐   │
│  │ JIAP Plugin (Kotlin)                            │   │
│  │  - HTTP Server (Port 25419)                     │   │
│  │  - Sidecar Manager                              │   │
│  │  - UI Integration                               │   │
│  └─────────────────────────────────────────────────┘   │
│              │  Process Management                      │
│              ▼                                          │
│  ┌─────────────────────────────────────────────────┐   │
│  │ MCP Companion Process (Python)                  │   │
│  │  - FastMCP Server (Port 25420)                  │   │
│  │  - HTTP Client to JIAP                          │   │
│  │  - Tool Definitions                             │   │
│  └─────────────────────────────────────────────────┘   │
└─────────────────────────────────────────────────────────┘
              │
              ▼
       AI Assistant (Claude, etc.)

Companion Process Lifecycle

Plugin Init: JIAP plugin loads and initializes
Server Start: HTTP server starts on configured port
Script Extraction: MCP scripts extracted to ~/.jiap/mcp/
Companion Launch: Background thread starts companion process
Health Monitoring: Process monitored for crashes
Auto-Restart: Failed processes automatically restarted
Clean Shutdown: Both processes stop together on unload

Troubleshooting

Companion Process Issues

Check logs: Look for [MCP Sidecar STDOUT] messages in JIAP logs
Verify Python: Ensure Python 3.10+ or uv is installed
Check dependencies: Plugin auto-checks for requests, fastmcp, pydantic
Manual path: Configure custom script path via GUI if needed

Connection Issues

Use health_check() to verify both servers are running
Check port conflicts with netstat -tlnp | grep 25419
Verify firewall allows localhost connections

Common Errors

E008: Install Python 3.10+ or uv
E009/E010: Check ~/.jiap/mcp/ permissions
E002: Change port in JIAP settings GUI
E014: Ensure JIAP plugin is enabled and loaded

Development

# Build JIAP Core
cd jiap
./gradlew dist

# Test MCP Server (optional, for development)
cd jiap/mcp_server
python jiap_mcp_server.py --url "http://127.0.0.1:25419"

License

GNU License 3.0 - see the LICENSE file for details.

Credits

skylot/jadx - The foundation of this project, a powerful JADX decompiler with plugin support
zinja-coder/jadx-ai-mcp - Inspired many ideas and approaches for JADX MCP integration

Jiap

Install / Use

README