eclipse rcp - Trying to create simple GEF -

i trying create simple automation tool testing.i have followed simple tutorials

on net , created rcp view on eclipse. have tried include simple gef

component on view throws me error saying " not create view: plug-in "geftutorial" unable instantiate class "geftutorial.view"."

here source code

particularly when uncomment creation of

 private scrollinggraphicalviewer viewer = new scrollinggraphicalviewer();  private rooteditpart rooteditpart = new scalablefreeformrooteditpart();  private editpartfactory editpartfactory = new simplegefeditpartfactory(); 

all above statements on view.my view appears back

here source code view.java

package geftutorial;  import org.eclipse.jface.viewers.istructuredcontentprovider;  import org.eclipse.jface.viewers.itablelabelprovider; import org.eclipse.jface.viewers.labelprovider; import org.eclipse.jface.viewers.tableviewer; import org.eclipse.jface.viewers.viewer; import org.eclipse.swt.swt; import org.eclipse.swt.graphics.color; import org.eclipse.swt.graphics.image; import org.eclipse.swt.widgets.composite; import org.eclipse.ui.isharedimages; import org.eclipse.ui.platformui; import org.eclipse.ui.part.viewpart; import org.eclipse.gef.*; import org.eclipse.gef.editparts.scalablefreeformrooteditpart; import org.eclipse.gef.ui.parts.scrollinggraphicalviewer;      public class view extends viewpart {     public static final string id = "geftutorial.view";      //use standard viewer draw2d canvas      private scrollinggraphicalviewer viewer = new scrollinggraphicalviewer();     //use standard rooteditpart holder other edit parts     private rooteditpart rooteditpart = new scalablefreeformrooteditpart();     //custom made editpartfactory, automatically called create     //edit     // parts model elements     private editpartfactory editpartfactory = new simplegefeditpartfactory();     //the model     private superwidget model;      //private tableviewer viewer;      /**      * content provider class responsible providing objects      * view. can wrap existing objects in adapters or return objects      * as-is. these objects may sensitive current input of view,      * or ignore , show same content (like task list,      * example).      */     class viewcontentprovider implements istructuredcontentprovider {         public void inputchanged(viewer v, object oldinput, object newinput) {         }          public void dispose() {         }          public object[] getelements(object parent) {             if (parent instanceof object[]) {                 return (object[]) parent;             }             return new object[0];         }     }      class viewlabelprovider extends labelprovider implements             itablelabelprovider {         public string getcolumntext(object obj, int index) {             return gettext(obj);         }          public image getcolumnimage(object obj, int index) {             return getimage(obj);         }          public image getimage(object obj) {             return platformui.getworkbench().getsharedimages().getimage(                     isharedimages.img_obj_element);         }     }      /**      * callback allow create viewer , initialize      * it.      */     public void createpartcontrol(composite parent) {         /*viewer = new tableviewer(parent, swt.multi | swt.h_scroll                 | swt.v_scroll);         viewer.setcontentprovider(new viewcontentprovider());         viewer.setlabelprovider(new viewlabelprovider());         // provide input contentprovider         viewer.setinput(new string[] {"one", "two", "three"});         */            //create dummy model         model = new superwidget("model");         model.createdummymodel();         //initialize viewer, 'parent'         // enclosing rcp windowframe         viewer.createcontrol(parent);         viewer.setrooteditpart(rooteditpart);         viewer.seteditpartfactory(editpartfactory);         //inject model viewer, viewer         // traverse model automatically         viewer.setcontents(model);         //set view's background white         viewer.getcontrol().setbackground(new color(null, 255,255,255));                 }      /**      * passing focus request viewer's control.      */     public void setfocus() {         viewer.getcontrol().setfocus();     } } 

can give me clue this? new rcp , gef :(

i'm learning gef, have seen gef editors not viewpart (views) editors, extending editpart.

check ongoing gef tutorial here. hope helps.

you can access other gef tutorial eclipse website.