Jar2Lib is a command line tool for generating C++ wrapper libraries around Java JAR files. It exposes the entire public Java API of the JAR in the corresponding C++ shared library, delegating to Java via JNI. The wrapping is performed using Jace.
Historical note: Jar2Lib was originally developed to integrate Bio-Formats with the Insight Toolkit, for use with the FARSIGHT project. However, we now have an dedicated inter-process solution for ITK integration instead which is easier to build from source, since it has no compile-time dependencies. Nonetheless, BF-CPP is still the recommended in-process solution for Bio-Formats native code integration.
We recommend using Jar2Lib via the cppwrap-maven-plugin; see "Installation and usage" below.
If you prefer to use Jar2Lib directly from the command line outside Maven:
- Download the JARs linked above, as well as Apache Velocity 1.7 and its dependencies.
- With all necessary JARs in your current working directory, you can run Jar2Lib on the command line as follows:
$ java -cp '*' loci.jar2lib.Jar2Lib
Usage: java loci.jar2lib.Jar2Lib projectId projectName
library.jar [library2.jar ...]
[-conflicts conflicts.txt] [-header header.txt]
[-extras cmake_extras.txt] [-output /path/to/output-project]
The easiest way to use Jar2Lib is via our cppwrap Maven plugin, which takes advantage of the Maven plug-in infrastructure to easily convert a Java library to C++ using Jar2Lib, without requiring any knowledge of Jar2Lib's workings or syntax. For example, it circumvents any need to download transitive dependencies.