private void addDevice(...)
{
    ...

    if(category == 19) {
        //c = DirectInputKeyboard.createKeyboard(lpDevice, subtype, productName, instanceName);
    }

    ...
}

package com.example;

import net.java.games.input.Axis;
import net.java.games.input.Controller;
import net.java.games.input.ControllerEnvironment;

public class ControllerExample 
{   
    static {
        try {
            System.setProperty("java.library.path", "C:/TEST/NativeDebug/lib/native/dxinput.dll");
            System.setProperty("jinput.plugins", "net.java.games.input.DirectInputEnvironmentPlugin");            
        }
        catch(Exception e) {
            System.out.println("Some error: " + e);
        }
    }
    
    public ControllerExample() 
    {
    }
    
    private void showControllers()
    {   
        System.out.println("Java Lib Path: " + System.getProperty("java.library.path"));
        System.out.println("Java Class Path: " + System.getProperty("java.class.path"));
        try {
            // accesses the default controller environment which contains all identified controllers                
            ControllerEnvironment ce = ControllerEnvironment.getDefaultEnvironment();
            // retrieve the available controllers
            Controller[] controllers = ce.getControllers();
                                       
            for(int i = 0; i < controllers.length; i++) {                
                System.out.println("Index: " + i + " - Controller type: " + controllers[i].getType() + " - Controller name: " + controllers[i].getName());
            }
        }
        catch(Exception e) {
            System.out.println("An error occurred: " + e);
            e.printStackTrace();
        }        
    }
    
    public static void main(String[] args)
    {
        new ControllerExample().showControllers();
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<project name="NativeDebug" default="default" basedir=".">
    <description>Builds, tests, and runs the project NativeDebug.</description>
    <import file="nbproject/build-impl.xml"/>

    <!-- ===================== Property Definitions =========================== -->
    
    <property name="controllerexample.mainclass" value="com.example.ControllerExample"/>

    <property name="app.name"     value="NativeDebug"/>

    <!-- Load the property app.version from the file which is itself specified by the property app.version
    The version number is used for various output files. -->
    <property file="version"/>

    <!-- This is the working directory for the compilation and jar file generation. --> 
    <property name="build.home"   value="build"/>  

    <!-- This is the target directory for the class files -->
    <property name="classes.home" value="${build.home}/classes"/>
  
    <!-- This is the directory to be used for certain tasks which need a temporary directory. -->
    <property name="scratch.home" value="${build.home}/scratch"/>

    <property name="dist.home"     value="dist"/>

    <!-- This is the directory where all kinds of supporting libraries reside. -->
    <property name="lib.home"    value="lib"/>  
    
    <!-- This is the directory where all external libraries reside which are neccessary when compiling or running the app. -->
    <property name="runtime.lib.home"     value="${lib.home}/runtime"/>

    <!-- Specifies the directory where the JInput plugins (jar files) reside. -->
    <property name="plugin.lib.home"     value="${lib.home}/plugin"/>

    <!-- Specifies the directory where the unpacked native libraries are. The unpacked native libraries are needed to run the app. -->
    <property name="native.lib.home" value="${lib.home}/native"/>
  
    <!-- This is the directory which contains the app's source code. -->
    <property name="src.home"      value="src"/>

    <!-- name of the output .jar file -->
    <property name="jar.name" value="jarfile.jar" />    

    <!-- The filename of the jar file which contains the classes. -->
    <property name="classes.jar.name" value="${app.name}-${app.version}.jar"/>

    <!-- The filename of the Jar file containing the resources. -->
    <property name="resources.jar.name" value="${app.name}-resources.jar"/>
  
    <!-- The file name of the source distribution. -->
    <property name="srcdist.file.name" value="${app.name}-${app.version}-src.zip"/>

    <!-- The top folder name inside the source distribution. -->
    <property name="srcdist.dir.name" value="${app.name}-${app.version}-src"/>

    <!-- ===================== End Property Definitions ======================= -->

    <!-- ==================== External Dependencies =========================== -->

    <!-- The fileset containing everything which selects everything that is needed to form the source distribution. -->
    <fileset id="srcdist.files" dir="${basedir}" >
    <include name="*.*"/>
   
    <!-- do not copy own build.properties -->
    <exclude name="build.properties"/>
   
    <include name="${lib.home}/**/*.*"/>
   
    <include name="${src.home}/**/*.*"/>
   
    <!-- Exclude any class files which may have been generated in the source code directory.  
           This happens when NetBeans is used as IDE. -->
    <exclude name="${src.home}/**/*.class"/> 
    </fileset>  

    <!-- This fileset contains everything that is needed to run the application. -->
    <fileset id="runtime.lib.files" dir="${runtime.lib.home}">
       <include name="*.jar"/>
    </fileset>
    
    <!-- This fileset contains the JInput plugins -->
    <fileset id="plugin.lib.files" dir="${plugin.lib.home}">
       <include name="*.jar"/>
    </fileset>
   
    <!-- ==================== Init Target ================================== -->

    <!-- Init creates the timestamp. -->
    <target name="init">
       <tstamp/>
       <mkdir dir="${scratch.home}"/>
    </target>
    
    <!-- ==================== Compilation Classpath =========================== -->

    <!-- This builds the classpath which is needed when the source gets compiled. -->

    <path id="compile.classpath">
       <fileset refid="runtime.lib.files"/>
    </path>

    <!-- This builds the classpath containing the JInput plugins. -->
    <path id="plugin.classpath">
       <fileset refid="plugin.lib.files"/>
    </path>

    <!-- ==================== Compile Target ================================== -->
    
    <target name="compile" depends="init" description="Compiles the sourcecode.">
      
      <mkdir  dir="${classes.home}"/>

      <!-- compile with given parameters -->
      <javac srcdir="${src.home}"
          destdir="${classes.home}">          
          <classpath refid="compile.classpath"/>
      </javac>
    </target>
    
    <!-- ==================== Create JAR ================================== -->   
       
    <target name="jar" depends="compile,-pre-jar" description="Create jar and MANIFEST.MF">

      <!-- create a property containing all .jar files, prefix lib/, and seperated with a space -->
      <pathconvert property="libs.project" pathsep=" ">
        <mapper>
          <chainedmapper>
            <!-- remove absolute path -->
            <flattenmapper />
            <!-- add lib/ prefix -->
            <globmapper from="*" to="lib/*" />
          </chainedmapper>
        </mapper>

        <path>
          <!-- lib.home contains all jar files, in several subdirectories -->
          <fileset dir="${lib.home}">
            <include name="**/*.jar" />
          </fileset>
        </path>
     </pathconvert>

     <!-- create the jar -->
     <jar jarfile="${build.home}/${jar.name}" basedir="${build.home}/classes">

       <!-- define MANIFEST.MF -->
       <manifest>
         <attribute name="Built-By" value="Anders" />
         <attribute name="Main-Class" value="com.example.ControllerExample" />
      
         <attribute name="Class-Path" value="${libs.project}" />
       </manifest>
     </jar>  

     <!-- ==================== Create JAR Dist ================================== -->
    
     <delete dir="${dist.home}" />

     <!-- contains all library dependencies -->
     <mkdir dir="${dist.home}/lib" />

     <copy todir="${dist.home}" file="${build.home}/${jar.name}" />
     <copy todir="${dist.home}/lib" filtering="off">

     <!-- remove the directory hierarchy: lib contains no subdirectories -->
     <flattenmapper />
     <fileset dir="${lib.home}" includes="**/*.jar" />
     </copy>
    
    </target>

    <!-- ======================== Run Target ================================= -->

    <target name="run" depends="compile, -determinePlugin">        
       <java fork="true" classname="${controllerexample.mainclass}" taskname="">
         <classpath>
   <path refid="compile.classpath"/>
                <path refid="plugin.classpath"/>
   <pathelement path="${classes.home}"/>
                <pathelement path="${src.home}"/>
        </classpath>
        <!-- TEMP these are set in java class..... -->
        <!-- <sysproperty key="java.library.path" value="${basedir}/${native.lib.home}"/> -->            
        <!-- <sysproperty key="jinput.plugins" value="${jinput.plugins}"/>  -->
      </java>
    </target>
  
    <target name="-determinePlugin">
      <condition property="jinput.plugins" value="net.java.games.input.DirectInputEnvironmentPlugin">
                <os family="windows"/>
      </condition>
      <condition property="jinput.plugins" value="net.java.games.input.OSXEnvironmentPlugin">
   <os family="mac"/>
      </condition>
      <condition property="jinput.plugins" value="de.bitecode.input.linux.LinuxInputEnvironmentPlugin">
   <and>
                    <os name="Linux"/>
                    <isset property="altplugin"/>
   </and>
      </condition>
      <condition property="jinput.plugins" value="net.java.games.input.LinuxEnvironmentPlugin">
   <os name="Linux"/>
      </condition>      
    </target>

    <target name="ControllerExample"
   description="starts example application">
               <property name="mainclass" value="${controllerexample.mainclass}"/>      
          <antcall target="run"/>
     </target>
</project>

static {
        try {
            System.setProperty("java.library.path", "C:/TEST/NativeDebug/lib/native/dxinput.dll");
            System.setProperty("jinput.plugins", "net.java.games.input.DirectInputEnvironmentPlugin");
            System.load("C:/TEST/NativeDebug/lib/native/dxinput.dll");            
        }
        catch(Exception e) {
            System.out.println("Error loading library: " + e);
        }
}

try {
    System.setProperty("java.library.path", "c:/MinAppFolder/MinApp/"); 
    System.load("c:/MinAppFolder/MinApp/dxinput.dll"); 
    // also tried System.loadLibrary("dxinput.dll") here...
}
catch(UnsatisfiedLinkError e) {
    System.out.println(e);
}