/** @see org.eclipse.core.commands.IHandler#execute(org.eclipse.core.commands.ExecutionEvent) */ @Override public Object execute(ExecutionEvent event) throws ExecutionException { if (MessageDialog.openQuestion( HandlerUtil.getActiveShell(event), "Clear source schemas", "Do you really want to clear all source schemas?")) { SchemaService ss = (SchemaService) PlatformUI.getWorkbench().getService(SchemaService.class); ss.clearSchemas(SchemaSpaceID.SOURCE); } return null; }