The missing bridge between Java and native C++.zip

JavaCPP ======= [](https://gitter.im/bytedeco/javacpp) [](https://maven-badges.herokuapp.com/maven-central/org.bytedeco/javacpp) [](http://bytedeco.org/builds/) [](https://travis-ci.org/bytedeco/javacpp) ^{Commercial support:} [](https://xscode.com/bytedeco/javacpp) Introduction ------------ JavaCPP provides efficient access to native C++ inside Java, not unlike the way some C/C++ compilers interact with assembly language. No need to invent new languages such as with [SWIG](http://www.swig.org/), [SIP](http://riverbankcomputing.co.uk/software/sip/), [C++/CLI](http://www.ecma-international.org/publications/standards/Ecma-372.htm), [Cython](http://www.cython.org/), or [RPython](https://rpython.readthedocs.io/). Instead, similar to what [cppyy](https://cppyy.readthedocs.io/) strives to do for Python, it exploits the syntactic and semantic similarities between Java and C++. Under the hood, it uses JNI, so it works with all implementations of Java SE, in addition to [Android](http://www.android.com/), [Avian](https://readytalk.github.io/avian/), and [RoboVM](http://robovm.mobidevelop.com/) ([instructions](#instructions-for-android-avian-and-robovm)). More specifically, when compared to the approaches above or elsewhere ([CableSwig](https://github.com/gccxml/CableSwig), [JNIGeneratorApp](http://www.eclipse.org/swt/jnigen.php), [cxxwrap](http://cxxwrap.sourceforge.net/), [JNIWrapper](http://www.teamdev.com/jniwrapper/), [Platform Invoke](https://docs.microsoft.com/en-us/dotnet/standard/native-interop/pinvoke), [GlueGen](http://jogamp.org/gluegen/www/), [LWJGL Generator](https://github.com/LWJGL/lwjgl3-wiki/wiki/4.3.-The-Generator), [JNIDirect](http://web.archive.org/web/20050329122501/http://homepage.mac.com/pcbeard/JNIDirect/), [ctypes](http://docs.python.org/library/ctypes.html), [JNA](https://github.com/java-native-access/jna), [JNIEasy](https://github.com/jmarranz/jnieasy), [JniMarshall](http://flinflon.brandonu.ca/Dueck/SystemsProgramming/JniMarshall/), [JNative](http://jnative.free.fr/), [J/Invoke](http://web.archive.org/web/20110727133817/http://www.jinvoke.com/), [HawtJNI](http://fusesource.github.io/hawtjni/), [JNR](https://github.com/jnr/), [BridJ](http://code.google.com/p/bridj/), [CFFI](https://cffi.readthedocs.io/), [fficxx](https://hackage.haskell.org/package/fficxx), [CppSharp](https://github.com/mono/CppSharp), [cgo](https://golang.org/cmd/cgo/), [pybind11](https://pybind11.readthedocs.io/), [rust-bindgen](https://rust-lang.github.io/rust-bindgen/), [Panama Native](http://jdk.java.net/panama/), etc.), it maps naturally and efficiently many common features afforded by the C++ language and often considered problematic, including overloaded operators, class and function templates, callbacks through function pointers, function objects (aka functors), virtual functions and member function pointers, nested struct definitions, variable length arguments, nested namespaces, large data structures containing arbitrary cycles, virtual and multiple inheritance, passing/returning by value/reference/string/vector, anonymous unions, bit fields, exceptions, destructors and shared or unique pointers (via either try-with-resources or garbage collection), and documentation comments. Obviously, neatly supporting the whole of C++ would require more work (although one could argue about the intrinsic neatness of C++), but we are releasing it here as a proof of concept. As a case in point, we have already used it to produce complete interfaces to OpenCV, FFmpeg, libdc1394, PGR FlyCapture, OpenKinect, videoInput, ARToolKitPlus, Leptonica, Tesseract, GSL, LLVM, HDF5, MKL, CUDA, Caffe, MXNet, TensorFlow, System APIs, and others as part of the [JavaCPP Presets](https://github.com/bytedeco/javacpp-presets) subproject, also demonstrating early parsing capabilities of C/C++ header files that show promising and useful results. Please feel free to ask questions on [the mailing list](http://groups.google.com/group/javacpp-project) or [the discussion forum](https://github.com/bytedeco/javacpp/discussions) if you encounter any problems with the software! I am sure it is far from perfect... Downloads --------- Archives containing JAR files are available as [releases](https://github.com/bytedeco/javacpp/releases). We can also have everything downloaded and installed automatically with: * Maven (inside the `pom.xml` file) ```xml <dependency> <groupId>org.bytedeco</groupId> <artifactId>javacpp</artifactId> <version>1.5.9</version> </dependency> ``` * Gradle (inside the `build.gradle` file) ```groovy dependencies { implementation group: 'org.bytedeco', name: 'javacpp', version: '1.5.9' } ``` * Leiningen (inside the `project.clj` file) ```clojure :dependencies [ [org.bytedeco/javacpp "1.5.9"] ] ``` * sbt (inside the `build.sbt` file) ```scala libraryDependencies += "org.bytedeco" % "javacpp" % "1.5.9" ``` Another option available to Gradle users is [Gradle JavaCPP](https://github.com/bytedeco/gradle-javacpp), and similarly for Scala users there is [SBT-JavaCPP](https://github.com/bytedeco/sbt-javacpp). Required Software ----------------- To use JavaCPP, you will need to download and install the following software: * An implementation of Java SE 7 or newer: * OpenJDK http://openjdk.java.net/install/ or * Oracle JDK http://www.oracle.com/technetwork/java/javase/downloads/ or * IBM JDK http://www.ibm.com/developerworks/java/jdk/ * A C++ compiler, out of which these have been tested: * GNU C/C++ Compiler (Linux, etc.) http://gcc.gnu.org/ * For Windows x86 and x64 http://mingw-w64.org/ * LLVM Clang (Mac OS X, etc.) http://clang.llvm.org/ * Microsoft C/C++ Compiler, part of Visual Studio https://visualstudio.microsoft.com/ * https://docs.microsoft.com/en-us/cpp/build/walkthrough-compiling-a-native-cpp-program-on-the-command-line To produce binary files for Android 4.0 or newer, you will also have to install: * Android NDK r7 or newer http://developer.android.com/ndk/downloads/ And similarly to target iOS, you will need to install either: * Gluon VM http://gluonhq.com/products/mobile/vm/ or * RoboVM 1.x or newer http://robovm.mobidevelop.com/downloads/ To modify the source code, please note that the project files were created for: * Maven 3.x http://maven.apache.org/download.html Finally, because we are dealing with native code, bugs can easily crash the virtual machine. Luckily, the HotSpot VM provides some tools to help us debug under those circumstances: * Troubleshooting Guide for Java SE with HotSpot VM * http://docs.oracle.com/javase/7/docs/webnotes/tsg/TSG-VM/html/ * http://docs.oracle.com/javase/8/docs/technotes/guides/troubleshoot/ Getting Started --------------- To understand how JavaCPP is meant to be used, one should first take a look at the [Mapping Recipes for C/C++ Libraries](https://github.com/bytedeco/javacpp/wiki/Mapping-Recipes), but a high-level overview of the [Basic Architecture](https://github.com/bytedeco/javacpp/wiki/Basic-Architec