Graphbuilder is not loading. Urgent help

When I am opening the Graphbuilder in SNAP it is giving the following exception. Request for help. Thanking you.

java.lang.NullPointerException
at java.util.ComparableTimSort.binarySort(Unknown Source)
at java.util.ComparableTimSort.sort(Unknown Source)
at java.util.Arrays.sort(Unknown Source)
at org.esa.snap.graphbuilder.rcp.dialogs.support.GraphPanel.CreateAddOpMenu(GraphPanel.java:100)
at org.esa.snap.graphbuilder.rcp.dialogs.support.GraphPanel.(GraphPanel.java:84)
at org.esa.snap.graphbuilder.rcp.dialogs.GraphBuilderDialog.initUI(GraphBuilderDialog.java:144)
at org.esa.snap.graphbuilder.rcp.dialogs.GraphBuilderDialog.(GraphBuilderDialog.java:125)
at org.esa.snap.graphbuilder.rcp.dialogs.GraphBuilderDialog.(GraphBuilderDialog.java:108)
at org.esa.snap.graphbuilder.rcp.actions.OpenGraphBuilderAction.actionPerformed(OpenGraphBuilderAction.java:55)
at org.openide.awt.AlwaysEnabledAction$1.run(AlwaysEnabledAction.java:199)
at org.openide.util.actions.ActionInvoker$1.run(ActionInvoker.java:95)
at org.openide.util.actions.ActionInvoker.doPerformAction(ActionInvoker.java:116)
at org.openide.util.actions.ActionInvoker.invokeAction(ActionInvoker.java:99)
at org.openide.awt.AlwaysEnabledAction.actionPerformed(AlwaysEnabledAction.java:202)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.AbstractButton.doClick(Unknown Source)
at com.jidesoft.plaf.vsnet.VsnetMenuItemUI.doClick(Unknown Source)
at com.jidesoft.plaf.vsnet.VsnetMenuItemUI$MouseInputHandler.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$500(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
[catch] at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:159)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)