Java3D SDN's HelloUniverse1 Help

Question

Hello, Im trying to learn Java3D, Im very new to Java as it is... im using SDN's HelloUniverse1 Example but am having real difficulties when trying to run it.
Im getting this error:
renderer.doWork(long) Line:776
renderer(J3dThread).run() Line: 250
Any ideas? (im using the eclipse IDE 3.2.0 with JRE System Library [J2SE1.5]j3dcore, j3dutils and vecmath)
thanks in advance
here is the code from HelloUniverse1
* @(#)HelloUniverse1.java 1.55 02/10/21 13:43:36
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* be used to endorse or promote products derived from this software without
* specific prior written permission.
* This software is provided "AS IS," without a warranty of any kind. ALL
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import java.applet.Applet;
import java.awt.BorderLayout;
import java.awt.GraphicsConfiguration;
import javax.media.j3d.Alpha;
import javax.media.j3d.BoundingSphere;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.RotationInterpolator;
import javax.media.j3d.Transform3D;
import javax.media.j3d.TransformGroup;
import javax.vecmath.Point3d;
import com.sun.j3d.utils.applet.MainFrame;
import com.sun.j3d.utils.geometry.ColorCube;
import com.sun.j3d.utils.universe.SimpleUniverse;
public class HelloUniverse1 extends Applet {
  private SimpleUniverse u = null;
  public BranchGroup createSceneGraph() {
    // Create the root of the branch graph
    BranchGroup objRoot = new BranchGroup();
    // Create the TransformGroup node and initialize it to the
    // identity. Enable the TRANSFORM_WRITE capability so that
    // our behavior code can modify it at run time. Add it to
    // the root of the subgraph.
    TransformGroup objTrans = new TransformGroup();
    objTrans.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
    objRoot.addChild(objTrans);
    // Create a simple Shape3D node; add it to the scene graph.
    objTrans.addChild(new ColorCube(0.4));
    // Create a new Behavior object that will perform the
    // desired operation on the specified transform and add
    // it into the scene graph.
    Transform3D yAxis = new Transform3D();
    Alpha rotationAlpha = new Alpha(-1, 4000);
    RotationInterpolator rotator = new RotationInterpolator(rotationAlpha,
        objTrans, yAxis, 0.0f, (float) Math.PI * 2.0f);
    BoundingSphere bounds = new BoundingSphere(new Point3d(0.0, 0.0, 0.0),
        100.0);
    rotator.setSchedulingBounds(bounds);
    objRoot.addChild(rotator);
    // Have Java 3D perform optimizations on this scene graph.
    objRoot.compile();
    return objRoot;
  public HelloUniverse1() {
  public void init() {
    setLayout(new BorderLayout());
    GraphicsConfiguration config = SimpleUniverse
        .getPreferredConfiguration();
    Canvas3D c = new Canvas3D(config);
    add("Center", c);
    // Create a simple scene and attach it to the virtual universe
    BranchGroup scene = createSceneGraph();
    u = new SimpleUniverse(c);
    // This will move the ViewPlatform back a bit so the
    // objects in the scene can be viewed.
    u.getViewingPlatform().setNominalViewingTransform();
    u.addBranchGraph(scene);
  public void destroy() {
    u.cleanup();
  // The following allows HelloUniverse to be run as an application
  // as well as an applet
  public static void main(String[] args) {
    new MainFrame(new HelloUniverse1(), 256, 256);
}

Answer 1

Ok, point taken...
where's a good place to learn "whats under the hood", most tutorials just say, "type into your command line: bla bla bla" without explaining why or what this includes when doing so or anything remotly interesting apart from what to type (not helpful when wanting to learn whats under the hood)
TIA