Disabling a PointLight throws CapabilityNotSetException

I have the following code for a light in Java3D. After my scene has been created, I have a separate thread which should turn the light off. When the my code calls:

setEnable(true);

I get a get the following error:

Exception in thread "Thread-3" javax.media.j3d.CapabilityNotSetException: Light: no capability to set light's state
    at javax.media.j3d.Light.setEnable(Light.java:281)
    at LightOnOff.run(Main.java:335)
    at java.lang.Thread.run(Unknown Source)

Here is my code for the light:

public class Lamp3D extends Group {

PointLight lampLight;

public Lamp3D() {

    this.createSceneGraph();

}

public void createSceneGraph() {
    TransformGroup transformGroup = new TransformGroup();
    Transform3D transform = new Transform3D();
    //Light
    lampLight = new PointLight(true,new Color3f(1.0f, 1.0f, 1.0f), new Point3f(-0.0f,1.62f, -0.0f), new Point3f(.0f, .6f, .0f)); 
    lampLight.setInfluencingBounds(new BoundingSphere(new Point3d(0f, 1.62f, -0.0f), 100));
    this.addChild(lampLight);

}
public PointLight getLampLight() {
    return lampLight;
}

And my main:

    BranchGroup group = new BranchGroup();
    TransformGroup transformGroup = new TransformGroup();
    Transform3D transform = new Transform3D();


    // LAMP 
    transformGroup = new TransformGroup();
    transform.setTranslation(new Vector3f(4.25f, 0.1f, -3.5f));
    transformGroup.setTransform(transform);

    Lamp3D lamp3D = new Lamp3D();
    transformGroup.addChild(lamp3D);    
    group.addChild(transformGroup);


    universe.getViewingPlatform().setNominalViewingTransform();

    // add the group of objects to the Universe

    universe.addBranchGraph(group);

            /*Viewing scene and moving around*/

    Canvas3D canvas = new Canvas3D(SimpleUniverse.getPreferredConfiguration());
    ViewingPlatform viewPlatform = universe.getViewingPlatform();
    BoundingSphere boundingSphere = new BoundingSphere(new Point3d(0f, 0f, 0f), 100f);
    OrbitBehavior orbitBehaviour = new OrbitBehavior(canvas,
            OrbitBehavior.REVERSE_ALL | OrbitBehavior.STOP_ZOOM);
    orbitBehaviour.setSchedulingBounds(boundingSphere);
    viewPlatform.setViewPlatformBehavior(orbitBehaviour);

            /*Viewing scene and moving around*/

    Thread t = new Thread(new LightOnOff(lamp3D));
    t.start();

Does anybody know why this is happening? Also should I be using behaviors to interact with the scene?

Solution

You need to set the proper capabilities of the light:

lampLight.setCapability(Light.ALLOW_STATE_WRITE);