Compiling

Prerequisites

• JDK7+
• C++
  • Linux: g++, clang or equivalent
  • macOS: XCode with Command Line Utilities
  • Windows: Microsoft Visual C++ (or cross-compile on Windows or Mac using mingw-w64)
• Maven, CMake
  • Linux: sudo apt install maven cmake g++
  • macOS: brew install maven cmake
  • Windows:: See Windows Build Environment

Steps

mvn             # compile for current system
mvn -P x86      # cross-compile using multi-lib for 32-bit x86 on current host OS(Linux/Unix, Windows) 
mvn -P x86_64   # cross-compile using multi-lib for 64-bit x86/amd64 on current host OS(Linux/Unix, MacOS, Windows)  
mvn -P ppc64    # cross-compile using multi-lib for PowerPC Linux/Unix
mvn -P armhf    # cross-compile using multi-lib for arm 32 bit hard floating point Linux/Unix
mvn -P aarch64  # cross-compile using multi-lib for arm64 based on current host OS (Linux/Unix, MacOS, Windows)
  ```

* **Important:** Call `mvn clean` between different compiler profiles.
* **Note:** For other cross-compilation profiles or platforms search for `CMAKE_TOOLCHAIN_FILE` in `pom.xml`.  Each has a respective CMake toolchain file.
* Prefer to skip maven? The project is configured to allow calling `cmake -DCMAKE_TOOLCHAIN_FILE=<...>` directly but the `javah` generated header file must be present.

### Package
Without recompiling native libraries
```bash
mvn -P package,jar-with-dependencies

Advanced

machine-dependent artefact

The build will output two .jar files in the target/ directory. One archive, which is build by the maven-jar-plugin, has a classifier which maches the machine's classifier (unless you are doing a cross-compile). This one will contain a freshly compiled library, like libjssc.so for Linux or a jssc.dll if you are on Windows. They go into a directory /natives/os_bitness.

»Uber-jar« artefact

The other .jar artifact which is generated by the build doesn't use the library compiled by cmake. It uses the checked-in libraries form the directory src/main/resources-precompiled/natives/. This jar is the artefact we are going to publish to maven central. It will contain a broader varieties of OSes and architectures in just one .jar file, but the libraries checked in into this git repository need to stay updated.

Creating just the »uber-jar« artefact

If you do not need a freshly compiled library, you can just execute mvn package -P package to skip the cmake compilation and the unit tests.