Not running the 1st program

Question

when i run:
import com.sun.j3d.utils.universe.SimpleUniverse;
import com.sun.j3d.utils.geometry.ColorCube;
import javax.media.j3d.BranchGroup;
public class Hello3d {
public Hello3d()
   SimpleUniverse universe = new SimpleUniverse();
   BranchGroup group = new BranchGroup();
   group.addChild(new ColorCube(0.3));
   universe.getViewingPlatform().setNominalViewingTransform();
   universe.addBranchGraph(group);
public static void main( String[] args ) {
   new Hello3d();
} // end of class Hello3dIt gives the following error. Why?
what should i do?
Error:
java.lang.UnsupportedClassVersionError: javax/media/j3d/Group (Unsupported major.minor version 49.0)
     at java.lang.ClassLoader.defineClass0(Native Method)
     at java.lang.ClassLoader.defineClass(Unknown Source)
     at java.security.SecureClassLoader.defineClass(Unknown Source)
     at java.net.URLClassLoader.defineClass(Unknown Source)
     at java.net.URLClassLoader.access$100(Unknown Source)
     at java.net.URLClassLoader$1.run(Unknown Source)
     at java.security.AccessController.doPrivileged(Native Method)
     at java.net.URLClassLoader.findClass(Unknown Source)
     at java.lang.ClassLoader.loadClass(Unknown Source)
     at java.lang.ClassLoader.loadClass(Unknown Source)
     at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
     at java.lang.ClassLoader.loadClass(Unknown Source)
     at java.lang.ClassLoader.loadClassInternal(Unknown Source)
Exception in thread "main"

Answer 1

According to the tutorial of Java3D.The basic outline of Java 3D program development consists of seven steps presented below:
1. Create a Canvas3D object
2. Create a VirtualUniverse object
3. Create a Locale object, attaching it to the VirtualUniverse object
4. Construct a view branch graph
a. Create a View object
b. Create a ViewPlatform object
c. Create a PhysicalBody object
d. Create a PhysicalEnvironment object
e. Attach ViewPlatform, PhysicalBody, PhysicalEnvironment, and Canvas3D objects to View
object
5. Construct content branch graph(s)
6. Compile branch graph(s)
7. Insert subgraphs into the Locale
        GraphicsConfiguration config =  SimpleUniverse.getPreferredConfiguration();
        Canvas3D canvas3D = new Canvas3D(config);
        add("Center", canvas3D);
        BranchGroup scene = createSceneGraph();
        SimpleUniverse simpleU = new SimpleUniverse(canvas3D);
        simpleU.getViewingPlatform().setNominalViewingTransform();
        simpleU.addBranchGraph(scene);