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Creating a Java Interface from a C ++ Header File

We have some proprietary libraries that we need to interact with. These libraries are Windows libraries or Linux.so files. We got headers for defining interfaces. Since I never did anything with my native libraries, I looked at JNAerator (http://code.google.com/p/jnaerator/) and the BridJ and JNA stuff.

What is an easy way to use a C ++ header file and compiled lib to create an interface? For example, accepting JNA in general with something like:

SomeDLL lib = (SomeDLL) Native.loadLibrary("some_dll", SomeDLL.class);

I need to maintain a DLL somewhere: how do I link a DLL with a Jar? I am using Maven to create a Jar file ... but the Native.loadLibrary interface does not allow a direct path.

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JNI coding is usually a manual process for writing C ++ code to create custom glue methods. There is a whole book that explains this.

In some cases, http://jna.java.net/ can automate or speed up this process, but not count on it.

You cannot “link native libraries” unless you follow the path of using OSGi or something like the Tanukisoft packaging tool; there is no built-in function in Java for this purpose.

You connect the dots with -Djava.library.path to tell java where to look for your own libraries, or use the lower-level APIs in System.loadLibrary that allow you to specify the full path.

Watch for interactions with PATH and LD_LIBRARY_PATH if your own libraries have dependencies in turn.

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With BridJ, you can compile the DLL / .so / .dylib just with the JAR, but you must put it (or them) on a specific platform-specific path in the JAR, which starts with "org / bridj / lib /" and ends with the platform architecture identifier +.

Here's a native BridJ source tree that shows this native linking scheme: org / bridj / lib directory

If you adhere to this convention, you will not be dealing with PATH, LD_LIBRARY_PATH or file extraction: BridJ.register() (called by @Library -nominated class with its own methods) will do it all for you!

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