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Java API for Vowpal Wabbit?

I am trying to use Vowpal Wabbit through Java. I have downloaded and successfully compiled the code from GitHub. The command line tool works fine.
After having a quick look at the repository (especially here), I can only assume that using it through Java is supposed to be already possible, and I don't really want to reinvent the wheel.
A wrapper around Vowpal Wabbit that allows use through Java. This wrapper is designed to be self contained. Because
of the use of JNI, a number of platforms are supported in this JAR.
I have added the maven dependency (found here) to my project, but without any kind of document, I don't really know where to start.
I have seen in another question that it seems to be possible to use VW with Java, but the guy only uses Runtime.getRuntime.exec() to call his bash command, and I can't find any documentation about any other way of doing (and there are only 2 questions mixing VW and Java on SO, which doesn't help).
I am new to JNI, so most likely there is something easy that I don't see.
To be perfectly clear, my questions are :
Should I just make a valid vw command and use it through Runtime.getRuntime.exec()? This doesn't seem to be the spirit of JNI, for there is no need for any wrapper/library for this. Plus, this doesn't make it very portable.
Where (the hell) is the (Java API) documentation ?
Any kind of help or guidance would be welcome.

I was one of the two primary authors of the VW JNI wrapper. Since the posting of this question the interface has significantly changed. We now encourage users to compile the native side on their own and provide it on the java.library.path. We have updated the README significantly to show how to use the library from Java.
I totally agree with your criticism that we have not published the Java API. I will work on that the next time I modify this code. In the meantime please feel free to clone the library and run mvn install and you can generate the Java API docs yourself. They should be quite detailed as we spent a lot of effort writing detailed docs.

You may checkout vowpal wabbit JNI wrapper we've built in Indeed: https://github.com/indeedeng/vowpal-wabbit-java.
We wrote integration test that can work as usage examples and we wrote API documentation as well. Check "using the library" section of README.
Hope this will help.

I don't think this adds a lot, but none of the previous answers really provided a clear answer. Like #Macchiatow mentioned, to use the Java wrapper which comes with Vowpal Wabbit, you would:
(on the project root dir) make all java or make java
cd into java and verify the installation with mvn test
you'd then mvn install to have the Java API jarred up and placed in your local maven repository. Supposedly this builds the JNI parts on your machine, so as to fit the C/C++ libraries of your platform if you have the necessary native C/C++ libraries installed and available to the make command.
you'd supposedly be able to include the vowpal package/s from those jars in the build tool used in your own project (ant/maven/boot/leiningen/sbt/etc. as in here).
For more background maybe see the Vowpal Wabbit Java readme. I think what it tries to say there, is that if you want a ready made jar from maven central, you should make sure it's the same vowpal version you're using, but without knowing more I'd guess if you built it like above, you are by definition using the same version.
I've had the above process work off a fresh clone, with Ubuntu 16.04 and Java 8.

This link may be of some help with regards to setting up a JNI wrapper.

I wasn't able to find Java API documentation anywhere, but Java code seems well documented - did you maybe try generating Javadoc yourself from the code?

There is indeed Java JNI wrapper to have a basic access to VW. By basic I mean to teach your model and to predict probability later on. They also provide Python library that can do far more than wrapper for Java. Recently I was forced to expose few more VW methods to Java by extending code provided.
Back to the questions:
Rather use the vw-jni artifact available in central maven repo and clone their code and run make all java. I some cases compiling code yourself will be the only solution, as for example provided artifact won't run on OpenSuse (my case)
Code available pretty straight forward. VWLearners::create is a factory to get an instance of VW from Java.

Native Source for java.awt.Robot

I am trying to find the native implementations of Java Robot functions. I found the Windows implementation here. Where can I find the mac and linux versions. I'm mainly trying to find out what it's doing to see how I can implement this functionality myself in C++.

Okay so I did some digging around and found what I was looking for. These may not be the latest versions but the metadata is there.
Linux: awt_robot.c
Mac: CRobot.m
Win: awt_robot.cpp

The source code of this class seems having no any native methods, probably calls are delegated somewhere else. In any case, OpenJDK seems a proper place to search as this is a complete project and not just part that is written in Java.

Java EE -- Configuration issues for a beginner

all. Relative rookie here who has spent the better part of three days just trying to get started with Java EE, and it's driving me up a wall. I've already read through numerous tutorials and consulted several book, so now I am turning to you.
I am starting from complete scratch, having uninstalled NetBeans and Glassfish and the Java EE SDK. My main issue is quite simply configuration. All the resources I've found typically say in a mere throwaway line: "Once you download the SDK, you must configure your environment for Java EE." But HOW? I need it in plain English. Even the most novice guides leave this basic stuff out. Does this mean editing the JAVA_HOME path or what? How does this configuration relate to the Java SE already on my system? Furthermore, I assume I don't need to also download the JDK with EE since I already have a JDK? (I am a Mac user, if that matters.)
I know I have a long, long way to go, so I appreciate any help I can get as I try to get this ball rolling. Much thanks in advance!

I think if you are using Netbeans then you don't have to worry about these things....
Simply File > New Project > Java Web > Web Application will help you get started with web applications..

Normally you would want to set the Java Home path so when you are compiling and running code your JDK is recognized. Sometimes IDEs come with their own JDK and then it really does not matter. However here is how you would set the path in different OS.
http://java.com/en/download/help/path.xml
For MAC I recommend this tutorial
http://lindaocta.com/?p=38

Make sure your JAVA_HOME is set in environment variables (just downloading SDK is not enough, you need to setup), I don't know how to do it mac, but in windows we setup my right click mycomputer-->Advanced-->Environment variables
Then install Netbeans, this step automatically searches for JAVA_HOME and assumes that SDK for all purposes. Then you are all set of programming.

If you don't mind switching to Eclipse can I recomend this tutorial An Eclipse / GlassFish / Java EE 6 Tutorial ignore the referance to Azzyzt tools and run through the tutorial step by step using GlassFish Tools Bundle for Eclipse.

How to run Java USB API for Windows using Eclipse

I understand that there is no complete support for USB for Java in Windows. But jUSB provides a Java USB API for windows which does not provide support for the complete functionality though.
I am trying to install the Java USB API and try it, and the steps provided say he following,
jUSB DLL
Copy the jusb.dll from the folder \InstallationFiles\JusbDll to the \system32 folder
of your Windows directory.
Compile the usb.windows package in Netbeans. Attach a USB device to the
USB and run RunUSBControllerTest.
I am a novice java user, and I currently work with Eclipse. I do not understand what to compile and how to run RunUSBControllerTest alone. Could someone please tell me how to run the application using Eclipse.
http://www.steelbrothers.ch/jusb/

There are other question in stackoverflow like this.
I recommended you:
Learn java before fight with this more complex and undocumented topic.
Use standards APIs like JSR-80. This standard could be a good search start point.
See this thread in forum.java.net
I hope this helps and good luck.

Dynamically loading a native library inside Java applet

I am trying to write a Java applet that will read from a user's serial port. For this I am using the Java Comm API in conjuction with the RXTX library. I've successfully managed to read data through a local Java application but I can't seem to do the same from within an applet. The problem is that the RXTX library is a native library and I haven't found a way to load this library inside the Java applet. I've found two interesting articles (Using JNI in Applets which references to this article), but both are over 10 years old and I am wondering if there is a newer solution. Or if you can suggest an alternative, I would love to hear it!

Use Java Web Start. You can include the native library as a signed jar and everything should work.
1) put the native librarys in a jar in the ROOT directory
2) sign ALL the jars
3) write a JNLP referencing all the jars (go do a search on how to write jnlp's)
after that it should work

Firstly I'd suggest doing that in an Applet is probably a bad idea.
If you do go ahead anyway, JNLPAppletLauncher may help.

I don't know about applets, other than they're locked down heavily wrt. security/accessing the machine's resources etc.
If you need a web-deployable solution, have you looked at Java Web Start ? See in particular this FAQ entry

Frankly, trying to access devices from a Java applet is a bad idea even if you could make it work, and loading a dynamic library into the conventional applet is an even worse idea; in fact, I'd be astounded if you could find a way to trick a modern browser into doing it. (Consider the possible security implications.)
You're better off, as suggested on other questions, building an app that can be launched with Web Start.

I'd be real interested in the answer here also. My suggestion would be to install the .jar and .dll for RXTX into the \program files\java\ tree. You could install them on the target system before trying to use the applet. I like the idea of using Java Web Start. If you sign the applet, can't you read/write any file on the machine? So you could install the .jar and .dll and then use them afterward?
For windows, I suggest using "Windows Java Serial Com Port Driver" rather than rxtx.
You can download it from http://www.engidea.com/blog/informatica/winjcom/winjcom.html
I've found it much easier to install and use and much more bug-free.
I was unable to use RXTX with USB serial devices because RXTX would crash when the USB port was unplugged. winjcom solved these problems for me, and more.
I'm still trying to decide how to deploy the DLL, but I'm not sweating it because I don't expect the DLL for "Windows Java Serial Com Port Driver" to change.
-Stosh