🦖 Wraptor

Wrap Java JARs into native, icon-branded Windows .exe launchers. No bundled JRE required. No third-party runtime. Just a small native stub and your JAR.

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What is this?

Wraptor is a desktop GUI (Java Swing) that takes your Java application — a main JAR plus its dependency JARs — and produces a real, double-clickable Windows .exe. That .exe isn't a zip-with-an-icon trick: it's a genuine PE executable with your icon, your company/version info, and (optionally) a UAC admin-privilege manifest baked directly into its Windows resources, wrapped around a tiny native launcher that finds a suitable JRE and starts your app.

No embedded browser, no Electron, no bundled 200MB runtime unless you explicitly want one — just your JARs and a ~250KB native stub.

✨ Features

• 🎨 Real icon embedding — your .ico is patched directly into the .exe's RT_GROUP_ICON/RT_ICON resources, not just a shortcut icon.
• 📋 Version info that shows up in Explorer — Company, File Description, Copyright, File/Product Version all appear under Properties → Details, like a "real" Windows app.
• ☕ JRE version enforcement, actually enforced — set a minimum/maximum Java version and the native launcher checks every candidate JRE it finds (bundled, registry, JAVA_HOME) and picks the best match, or fails with a clear message instead of silently launching the wrong one.
• 🔐 UAC admin manifest — optionally require elevation on launch.
• 🪟 32-bit and 64-bit builds from one project, in one click.
• 🔒 Single-instance mode — prevent a second copy of your app from starting.
• 🧵 Crash-visible launcher — if your app throws on startup, the native stub captures its stdout/stderr and shows it in a message box instead of silently vanishing.
• 🧭 Real-time validation — the build refuses to run with a missing main jar, invalid app name, unwritable output folder, or malformed main class, and tells you exactly which one.

🧠 How it works

Wraptor is really two separate programs working together:

flowchart TB
    subgraph BUILD["🛠️ Build time — Wraptor.exe (Java Swing + JNA)"]
        A["You configure a project:<br/>JARs, icon, version info, JRE range"] --> B["Wraptor copies a prebuilt<br/>native launcher stub"]
        B --> C["JNA calls Win32<br/>BeginUpdateResource / UpdateResource /<br/>EndUpdateResource"]
        C --> D["Icon, version info, admin manifest,<br/>and a CONFIG + JARS resource<br/>get patched into the stub"]
    end

    D --> E["YourApp.exe"]

    subgraph RUNTIME["🚀 Runtime — YourApp.exe (native C, no JVM yet)"]
        E --> F["Reads its own embedded<br/>CONFIG + JARS resources"]
        F --> G["Extracts JARs to a temp folder"]
        G --> H["Finds a JRE satisfying<br/>your min/max version,<br/>checking bundled → registry → JAVA_HOME"]
        H --> I["Launches javaw.exe<br/>with the right classpath + main class"]
        I --> J["Captures stdout/stderr;<br/>shows a crash dialog on failure"]
    end

Loading

The native launcher (stub.c) is a small, dependency-light Win32 program compiled once per architecture with MinGW-w64. Its compiled bytes are embedded directly into Wraptor's own .class file as base64 (EmbeddedStubs.java) — no loose resource files that can go missing from a build, and no per-project recompilation needed. Every .exe Wraptor produces is a copy of that same stub with your project's resources patched in.

🚀 Getting started

Prerequisites

For	You need
Building/running the Wraptor GUI	JDK 8+, NetBeans (or Ant directly)
Rebuilding the native stub	Windows + MSYS2 with both the mingw-w64-i686-toolchain and mingw-w64-x86_64-toolchain packages installed
Using Wraptor to build an app	Just a JRE — MSYS2 is only needed if you're modifying the native stub itself

1. Build the Java GUI

The JNA jar is already vendored under Wraptor/src/lib/, so no dependency download is needed.

# Open Wraptor/ in NetBeans and hit Build, or from the command line:
cd Wraptor
ant jar

This produces dist/Wraptor.jar — run it with java -jar Wraptor.jar.

2. (Optional) Rebuild the native launcher stub

You only need this if you're changing stub.c itself — the prebuilt stub bytes already shipped in EmbeddedStubs.java are enough to build apps out of the box.

From Wraptor/native-stub/, with MSYS2 installed:

build-all.bat

This runs, in order:

1. compile-stub.bat — cross-compiles stub.c into stub32.exe and stub64.exe with MinGW-w64.
2. copy-to-project.bat — copies the fresh stubs into src/native/.
3. generate-embedded-stubs.bat — base64-encodes both stubs and regenerates src/wraptor/resource/EmbeddedStubs.java.

Then do a Clean and Build on the Wraptor project in NetBeans to pick up the change.

3. Use Wraptor to build your app

1. JARs tab — add your main jar and any dependency jars. If exactly one of them declares a Main-Class in its manifest, it's auto-flagged as the main jar; otherwise right-click one → Set as Main Jar.
2. Application tab — app name, output folder, icon, target OS versions, architecture(s), admin/single-instance flags.
3. Java tab — main class (auto-filled from the main jar's manifest), JVM arguments, JRE min/max version.
4. EXE Info tab — file/product version, company name, description, copyright — shown in Explorer's Properties dialog.
5. Hit Build EXE.

Your .exe(s) land in the output folder you chose, ready to double-click.

🩹 Troubleshooting

• libgcc_s_dw2-1.dll was not found while recompiling the stub — MinGW's compiler frontend spawns helper processes (cc1.exe, as.exe) that need mingw32\bin/mingw64\bin on PATH to find their own runtime DLLs. compile-stub.bat sets this for you; if you're invoking the compiler manually, make sure that directory is on PATH.
• Antivirus flags the generated .exe or slows down a build — unsigned launcher stubs that self-extract JARs at runtime are a common false-positive pattern for heuristic AV engines. Adding an exclusion for your output folder avoids build-time file-lock races too.
• App launches, then immediately closes with no error — check the exit code (echo %ERRORLEVEL% right after running it from a command prompt). A code of 0 means your app exited normally (e.g. an uncaught exception was already handled and it returned early); non-zero means the launcher's crash dialog should have shown the captured output.

📄 License

MIT — see LICENSE.