Bug 114721 NPE thrown out when preview cascading parameter which binding data set deleted
description: NPE thrown out when preview cascading parameter which binding data set deleted steps to reproduce: 1. create a cascading parameter which binds to data set 2. select the data set in data explorer and delete it 3. click on Preview button actual result: NPE thrown out expected result: No exception thrown out exception stack trace: java.lang.NullPointerException at org.eclipse.birt.report.designer.internal.ui.dialogs.InputParameterDialog.getCo mboSelectionLabel(InputParameterDialog.java:929) at org.eclipse.birt.report.designer.internal.ui.dialogs.InputParameterDialog.getIn itValue(InputParameterDialog.java:903) at org.eclipse.birt.report.designer.internal.ui.dialogs.InputParameterDialog.getPa rameterValue(InputParameterDialog.java:774) at org.eclipse.birt.report.designer.internal.ui.dialogs.InputParameterDialog.isEna ble(InputParameterDialog.java:1076) at org.eclipse.birt.report.designer.internal.ui.dialogs.InputParameterDialog.isEna ble(InputParameterDialog.java:1066) at org.eclipse.birt.report.designer.internal.ui.dialogs.InputParameterDialog.enabl eOkButton(InputParameterDialog.java:1048) at org.eclipse.birt.report.designer.internal.ui.dialogs.InputParameterDialog.initD ialog(InputParameterDialog.java:1109) at org.eclipse.birt.report.designer.internal.ui.dialogs.BaseDialog.open (BaseDialog.java:137) at org.eclipse.birt.report.designer.internal.ui.editors.parts.AbstractMultiPageLay outEditor.prePreview(AbstractMultiPageLayoutEditor.java:1100) at org.eclipse.birt.report.designer.internal.ui.editors.parts.AbstractMultiPageLay outEditor.pageChange(AbstractMultiPageLayoutEditor.java:948) at org.eclipse.birt.report.designer.ui.editors.ReportEditor.pageChange (ReportEditor.java:170) at org.eclipse.ui.part.MultiPageEditorPart$2.widgetSelected (MultiPageEditorPart.java:200) at org.eclipse.swt.widgets.TypedListener.handleEvent (TypedListener.java:90) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:66) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:843) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:867) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:852) at org.eclipse.swt.widgets.Widget.notifyListeners(Widget.java:660) at org.eclipse.swt.custom.CTabFolder.setSelection(CTabFolder.java:3138) at org.eclipse.swt.custom.CTabFolder.onMouse(CTabFolder.java:1922) at org.eclipse.swt.custom.CTabFolder$1.handleEvent(CTabFolder.java:288) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:66) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:843) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3080) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2713) at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:1699) at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:1663) at org.eclipse.ui.internal.Workbench.createAndRunWorkbench (Workbench.java:367) at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:143) at org.eclipse.ui.internal.ide.IDEApplication.run (IDEApplication.java:103) at org.eclipse.core.internal.runtime.PlatformActivator$1.run (PlatformActivator.java:226) at org.eclipse.core.runtime.adaptor.EclipseStarter.run (EclipseStarter.java:376) at org.eclipse.core.runtime.adaptor.EclipseStarter.run (EclipseStarter.java:163) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke (NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:324) at org.eclipse.core.launcher.Main.invokeFramework(Main.java:334) at org.eclipse.core.launcher.Main.basicRun(Main.java:278) at org.eclipse.core.launcher.Main.run(Main.java:973) at org.eclipse.core.launcher.Main.main(Main.java:948)
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/GetParameterDefinitionTask.java
Iterator iter2 = ( ( ParameterGroupDefn ) pBase )
							.getContents( ).iterator( );
					while ( iter2.hasNext( ) )
					{
						IParameterDefnBase p = ( IParameterDefnBase ) iter2
								.next( );
						if ( p instanceof ScalarParameterDefn )
						{
							( ( ScalarParameterDefn ) p )
									.setReportDesign( runnable
											.getDesignHandle( ).getDesign( ) );
							( ( ScalarParameterDefn ) p ).setLocale( locale );
							( ( ScalarParameterDefn ) p )
									.evaluateSelectionList( );
						}
					}
				}
			}
		}
		return parameterDefns;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.engine.api2.IGetParameterDefinitionTask#evaluateDefaults()
	 */
	public void evaluateDefaults( ) throws EngineException
	{
	}
	/*