This Java tip demonstrates the use of scoping for controlling the influence of lights.

 import java.applet.Applet;
import java.awt.BorderLayout;

import javax.media.j3d.AmbientLight;
import javax.media.j3d.Appearance;
import javax.media.j3d.Background;
import javax.media.j3d.BoundingSphere;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.DirectionalLight;
import javax.media.j3d.GeometryArray;
import javax.media.j3d.Material;
import javax.media.j3d.PointLight;
import javax.media.j3d.PolygonAttributes;
import javax.media.j3d.QuadArray;
import javax.media.j3d.Shape3D;
import javax.media.j3d.Transform3D;
import javax.media.j3d.TransformGroup;
import javax.media.j3d.TriangleStripArray;
import javax.vecmath.Color3f;
import javax.vecmath.Point3f;
import javax.vecmath.Vector3f;

import com.sun.j3d.utils.applet.MainFrame;
import com.sun.j3d.utils.geometry.Box;
import com.sun.j3d.utils.universe.SimpleUniverse;

/**
 * LightScopeApp creates a scene that is paritally light by a light using the
 * scoping feature.
 */
public class LightScopeApp extends Applet {

  Appearance createMaterialAppearance(Color3f color) {
    Appearance appear = new Appearance();
    Material material = new Material();
    material.setDiffuseColor(color);
    material.setShininess(50.0f);
    appear.setMaterial(material);

    return appear;
  }

  Shape3D createXZPlane(Point3f p0, Point3f p1, Point3f p2, Point3f p3) {
    Shape3D plane = new Shape3D();QuadArray planeGeom = new QuadArray(4, QuadArray.COORDINATES
        | QuadArray.NORMALS);
    planeGeom.setCoordinate(0, p0);
    planeGeom.setCoordinate(1, p1);
    planeGeom.setCoordinate(2, p2);
    planeGeom.setCoordinate(3, p3);
    Vector3f norm = new Vector3f(0.0f, 1.0f, 0.0f);
    planeGeom.setNormal(0, norm);
    planeGeom.setNormal(1, norm);
    planeGeom.setNormal(2, norm);
    planeGeom.setNormal(3, norm);
    plane.setGeometry(planeGeom);
    return plane;
  }

  Shape3D createLampShape() {
    Shape3D lamp = new Shape3D();
    int stripCounts[] = { 10, 10 };
    TriangleStripArray lampGeom = new TriangleStripArray(20,
        GeometryArray.COORDINATES | GeometryArray.NORMALS, stripCounts);
    lampGeom.setCoordinate(0, new Point3f(-0.01f, 0.9f, 0.01f));
    lampGeom.setCoordinate(1, new Point3f(-0.01f, 0.0f, 0.01f));
    lampGeom.setCoordinate(2, new Point3f(0.01f, 0.9f, 0.01f));
    lampGeom.setCoordinate(3, new Point3f(0.01f, 0.0f, 0.01f));
    lampGeom.setCoordinate(4, new Point3f(0.01f, 0.9f, -0.01f));
    lampGeom.setCoordinate(5, new Point3f(0.01f, 0.0f, -0.01f));
    lampGeom.setCoordinate(6, new Point3f(-0.01f, 0.9f, -0.01f));
    lampGeom.setCoordinate(7, new Point3f(-0.01f, 0.0f, -0.01f));
    lampGeom.setCoordinate(8, new Point3f(-0.01f, 0.9f, 0.01f));
    lampGeom.setCoordinate(9, new Point3f(-0.01f, 0.0f, 0.01f));
    lampGeom.setCoordinate(10, new Point3f(-0.1f, 0.9f, 0.1f));
    lampGeom.setCoordinate(11, new Point3f(-0.2f, 0.5f, 0.2f));
    lampGeom.setCoordinate(12, new Point3f(0.1f, 0.9f, 0.1f));
    lampGeom.setCoordinate(13, new Point3f(0.2f, 0.5f, 0.2f));
    lampGeom.setCoordinate(14, new Point3f(0.1f, 0.9f, -0.1f));
    lampGeom.setCoordinate(15, new Point3f(0.2f, 0.5f, -0.2f));
    lampGeom.setCoordinate(16, new Point3f(-0.1f, 0.9f, -0.1f));
    lampGeom.setCoordinate(17, new Point3f(-0.2f, 0.5f, -0.2f));
    lampGeom.setCoordinate(18, new Point3f(-0.1f, 0.9f, 0.1f));
    lampGeom.setCoordinate(19, new Point3f(-0.2f, 0.5f, 0.2f));

    Vector3f norm = new Vector3f(-0.7f, 0.0f, 0.7f);
    lampGeom.setNormal(0, norm);
    lampGeom.setNormal(1, norm);
    norm.set(0.7f, 0.0f, 0.7f);
    lampGeom.setNormal(2, norm);
    lampGeom.setNormal(3, norm);
    norm.set(0.7f, 0.0f, -0.7f);
    lampGeom.setNormal(4, norm);
    lampGeom.setNormal(5, norm);
    norm.set(-0.7f, 0.0f, -0.7f);
    lampGeom.setNormal(6, norm);
    lampGeom.setNormal(7, norm);
    norm.set(-0.7f, 0.0f, 0.7f);
    lampGeom.setNormal(8, norm);
    lampGeom.setNormal(9, norm);
    norm.set(-0.7f, 0.0f, 0.7f);
    lampGeom.setNormal(10, norm);
    lampGeom.setNormal(11, norm);
    norm.set(0.7f, 0.0f, 0.7f);
    lampGeom.setNormal(12, norm);
    lampGeom.setNormal(13, norm);
    norm.set(0.7f, 0.0f, -0.7f);
    lampGeom.setNormal(14, norm);
    lampGeom.setNormal(15, norm);
    norm.set(-0.7f, 0.0f, -0.7f);
    lampGeom.setNormal(16, norm);
    lampGeom.setNormal(17, norm);
    norm.set(-0.7f, 0.0f, 0.7f);
    lampGeom.setNormal(18, norm);
    lampGeom.setNormal(19, norm);

    lamp.setGeometry(lampGeom);
    return lamp;
  }

  BranchGroup createScene() {
    BranchGroup scene = new BranchGroup();
    TransformGroup tableTG = new TransformGroup();
    TransformGroup lampTG = new TransformGroup();
    TransformGroup litBoxTG = new TransformGroup();
    TransformGroup unLitBoxTG = new TransformGroup();

    scene.addChild(tableTG);
    tableTG.addChild(lampTG);
    tableTG.addChild(litBoxTG);
    tableTG.addChild(unLitBoxTG);

    Color3f white = new Color3f(1.0f, 1.0f, 1.0f);
    Color3f red = new Color3f(1.0f, 0.0f, 0.0f);
    Color3f blue = new Color3f(0.0f, 1.0f, 0.0f);
    Color3f green = new Color3f(0.0f, 0.0f, 1.0f);
    Color3f black = new Color3f(0.0f, 0.0f, 0.0f);

    Vector3f transVector = new Vector3f();
    Transform3D transTransform = new Transform3D();

    transVector.set(0.0f, -0.4f, 0.5f);
    transTransform.setTranslation(transVector);
    tableTG.setTransform(transTransform);

    transVector.set(-0.4f, 0.001f, 0.1f);
    transTransform.setTranslation(transVector);
    lampTG.setTransform(transTransform);

    transVector.set(-0.2f, 0.1f, 0.2f);
    transTransform.setTranslation(transVector);
    litBoxTG.setTransform(transTransform);

    transVector.set(0.3f, 0.1f, -0.4f);
    transTransform.setTranslation(transVector);
    unLitBoxTG.setTransform(transTransform);

    Shape3D tablePlane = createXZPlane(new Point3f(-1.0f, 0.0f, -1.0f),
        new Point3f(-1.0f, 0.0f, 1.0f), new Point3f(1.0f, 0.0f, 1.0f),
        new Point3f(1.0f, 0.0f, -1.0f));
    tablePlane.setAppearance(createMaterialAppearance(white));
    tableTG.addChild(tablePlane);
    litBoxTG.addChild(new Box(0.1f, 0.1f, 0.1f, Box.GENERATE_NORMALS,
        createMaterialAppearance(red)));
    Shape3D shadowPlane = createXZPlane(new Point3f(0.1f, -0.095f, -0.1f),
        new Point3f(0.1f, -0.095f, 0.1f), new Point3f(0.2f, -0.095f,
            0.15f), new Point3f(0.2f, -0.095f, -0.15f));
    shadowPlane.setAppearance(createMaterialAppearance(black));
    litBoxTG.addChild(shadowPlane);

    Appearance redGlowMat = createMaterialAppearance(red);
    //    redGlowMat.getMaterial().setEmissiveColor(0.5f, 0.5f, 0.5f);
    unLitBoxTG.addChild(new Box(0.1f, 0.1f, 0.1f, Box.GENERATE_NORMALS,
        redGlowMat));

    Shape3D lamp = createLampShape();
    Appearance lampAppearance = createMaterialAppearance(blue);
    PolygonAttributes polyAttrib = new PolygonAttributes();
    polyAttrib.setCullFace(PolygonAttributes.CULL_NONE);
    polyAttrib.setBackFaceNormalFlip(true);
    lampAppearance.setPolygonAttributes(polyAttrib);
    lamp.setAppearance(lampAppearance);
    lampTG.addChild(lamp);

    PointLight lampLight = new PointLight();
    lampLight.setPosition(0.1f, 0.5f, -0.1f);
    lampLight.setInfluencingBounds(new BoundingSphere());
    lampTG.addChild(lampLight);

    Shape3D litPlane = createXZPlane(new Point3f(-0.4f, 0.0f, -0.4f),
        new Point3f(-0.4f, 0.0f, 0.4f), new Point3f(0.4f, 0.0f, 0.4f),
        new Point3f(0.4f, 0.0f, -0.4f));
    litPlane.setAppearance(createMaterialAppearance(white));
    lampTG.addChild(litPlane);

    lampLight.addScope(lampTG);
    lampLight.addScope(litBoxTG);

    AmbientLight lightA = new AmbientLight();
    lightA.setInfluencingBounds(new BoundingSphere());
    scene.addChild(lightA);

    DirectionalLight lightD1 = new DirectionalLight();
    lightD1.setInfluencingBounds(new BoundingSphere());
    lightD1.setColor(new Color3f(0.4f, 0.4f, 0.4f));
    Vector3f lightDir = new Vector3f(-1.0f, -1.0f, -1.0f);
    lightDir.normalize();
    lightD1.setDirection(lightDir);
    scene.addChild(lightD1);

    DirectionalLight lightD2 = new DirectionalLight();
    lightD2.setInfluencingBounds(new BoundingSphere());
    lightD2.setColor(new Color3f(0.2f, 0.2f, 0.2f));
    lightDir.set(1.0f, -1.0f, -1.0f);
    lightDir.normalize();
    lightD2.setDirection(lightDir);
    scene.addChild(lightD2);

    Background bg = new Background();
    bg.setColor(1.0f, 1.0f, 1.0f);
    bg.setApplicationBounds(new BoundingSphere());
    scene.addChild(bg);

    return scene;
  }

  public LightScopeApp() {
    setLayout(new BorderLayout());
    Canvas3D c = new Canvas3D(null);
    add("Center", c);

    BranchGroup scene = createScene();
    scene.compile();

    SimpleUniverse 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 static void main(String argv[]) {
    new MainFrame(new LightScopeApp(), 256, 256);
  }
}