@Override
    public void simpleInitApp() {

        /* create a blue box at coordinates (1,-1,1) */
        Box box1 = new Box(1,1,1);
        Geometry blue = new Geometry("Box", box1);
        blue.setLocalTranslation(new Vector3f(1,-1,1));
        Material mat1 = new Material(assetManager, 
                "Common/MatDefs/Misc/Unshaded.j3md");
        mat1.setColor("Color", ColorRGBA.Blue);
        blue.setMaterial(mat1);

        /* create a red box straight above the blue one at (1,3,1) */
        Box box2 = new Box(1,1,1);      
        Geometry red = new Geometry("Box", box2);
        red.setLocalTranslation(new Vector3f(1,3,1));
        Material mat2 = new Material(assetManager, 
                "Common/MatDefs/Misc/Unshaded.j3md");
        mat2.setColor("Color", ColorRGBA.Red);
        red.setMaterial(mat2);

        /* Create a pivot node at (0,0,0) and attach it to the root node */
        Node pivot = new Node("pivot");
        rootNode.attachChild(pivot); // put this node in the scene

        /* Attach the two boxes to the *pivot* node. (And transitively to the root node.) */
        pivot.attachChild(blue);
        pivot.attachChild(red);
        /* Rotate the pivot node: Note that both boxes have rotated! */
        pivot.rotate(.4f,.4f,0f);
    }
Sample 2 - How to use nodes as handles to manipulate objects in the scene.
You can rotate, translate, and scale objects by manipulating their parent nodes.
The Root Node is special: Only what is attached to the Root Node appears in the scene.
jme3-examples/src/main/java/jme3test/helloworld/HelloNode.java