[news.eclipse.helpwanted] Re: Problems with Table in RCP

[John Arthorne <john@xxxxxxxxxxxxxx>]

You are asking in the wrong place.  See the thread in this newsgroup 
entitled "POSTING GUIDELINES".
--

Jan-Paul Nachtwey wrote:
> Hi,
>
> I have a problem with the columns of a table. I wrote an RCP-Application 
> and get a NullPointerException when closing this Application. Here is 
> the Code I wrote, followed by the Stacktrace of the Exception:
>
>
> public class PartDetailsPage implements IDetailsPage {
>
>     String[] units = UnitLoader.getInstance().getUnitsAsString();
>
>     protected static final Logger log = 
> Logger.getLogger(PartDetailsPage.class);
>
>     class PartsContentProvider implements IStructuredContentProvider {
>
>         protected final Logger log = Logger
>                 .getLogger(PartsContentProvider.class);
>
>         public Object[] getElements(Object inputElement) {
>             if (inputElement instanceof Part) {
>                 Part part = (Part)inputElement;
>                 Object[] returnObjectArray = 
> part.getIngredients().toArray();
>                 return returnObjectArray;
>             }
>
>             log.error("getElements returns with null!");
>
>             return new Object[0];
>         }
>
>         public void dispose() {
>         }
>
>         public void inputChanged(Viewer viewer, Object oldInput, Object 
> newInput) {
>             viewer.refresh();
>         }
>     }
>
>     class PartsLabelProvider extends LabelProvider implements 
> ITableLabelProvider {
>
>         protected final Logger log = 
> Logger.getLogger(PartsLabelProvider.class);
>
>         public Image getColumnImage(Object element, int columnIndex) {
>
>             Image returnImage = null;
>
>             switch (columnIndex) {
>                 case 0: returnImage = returnImage = 
> CorePlugin.getDefault().getImage(
>                         CorePlugin.IMG_FOOD);
>                         break;
>             }
>             return returnImage;
>         }
>
>         public String getColumnText(Object element, int columnIndex) {
>             if (!(element instanceof Ingredient)) return "";
>             Ingredient ing = (Ingredient)element;
>
>             String returnString = "";
>
>             switch (columnIndex) {
>                 case 0: returnString = ing.getAmount(); break;
>                 case 1: returnString = ing.getUnit().getId(); break;
>                 case 2: returnString = 
> ing.getFood().getFood().toString(ing.getAmount());
>             }
>             return returnString;
>         }
>
>     }
>
>     class IngredientCellModifier implements ICellModifier {
>
>         public boolean canModify(Object element, String property) {
>             if (element instanceof Ingredient) {
>                 int index = 
> Arrays.asList(ingredientViewer.getColumnProperties())
>                         .indexOf(property);
>                 switch (index) {
>                 case 0:
>                     return true;
>                 case 1:
>                     return true;
>                 case 2:
>                     return false;
>                 }
>             }
>             if (element instanceof String) return true;
>
>             return false;
>         }
>
>         public Object getValue(Object element, String property) {
>             if (element instanceof Ingredient) {
>                 Ingredient ing = (Ingredient) element;
>                 int index = 
> Arrays.asList(ingredientViewer.getColumnProperties())
>                         .indexOf(property);
>                 switch (index) {
>                 case 0:
>                     return ing.getAmount();
>                 case 1:
>                     for (int i =0; i<units.length; i++ ) {
>                         if (units[i].equals(ing.getUnit().getId())) 
> return new Integer(i);
>                     }
>                     return new Integer(0);
>                 case 2:
>                     return 
> ing.getFood().getFood().toString(ing.getAmount());
>                 }
>             }
>             return null;
>         }
>
>         public void modify(Object element, String property, Object value) {
>             Ingredient ing = (Ingredient) ((TableItem) element)
>                     .getData();
>             int index = 
> Arrays.asList(ingredientViewer.getColumnProperties())
>                     .indexOf(property);
>             SimpleDateFormat sdf = new SimpleDateFormat(Messages
>                     .getString("dateFormat")); //$NON-NLS-1$
>             switch (index) {
>             case 0:
>                 ing.setAmount(value.toString());
>                 break;
>             case 1:
>
> ing.setUnit(UnitLoader.getInstance().loadUnit(units[((Integer)value).intValue()])); 
>
>                 break;
>             case 2: break;
>             }
>             ingredientViewer.refresh(true);
>         }
>     }
>
>     private IManagedForm mform;
>     private Part input;
>     private TableViewer ingredientViewer;
>     private Text steps;
>
>     public PartDetailsPage() {
>         super();
>     }
>
>     public void createContents(final Composite parent) {
>         GridLayout layout = new GridLayout(2, false);
>     layout.marginHeight = 5;
>     layout.marginWidth = 5;
>     parent.setLayout(layout);
>
>     FormToolkit toolkit = mform.getToolkit();
>     final Section s1 = toolkit.createSection(parent, Section.EXPANDED | 
> Section.COMPACT | Section.TWISTIE);
>     s1.marginWidth = 10;
>     s1.marginHeight = 10;
>     s1.setText("Ingredients");
>     s1.setDescription("Insert all the properties for one part of the 
> recipe");
>     s1.addExpansionListener(new IExpansionListener() {
>             public void expansionStateChanging(ExpansionEvent e) {
>             }
>
>             public void expansionStateChanged(ExpansionEvent e) {
>                 if (!(s1.isExpanded())) {
>                     parent.pack();
>                 }
>            }
>     });
>     GridData gd = new GridData(GridData.FILL_BOTH);
>     s1.setLayoutData(gd);
>     toolkit.createCompositeSeparator(s1);
>     Composite client = toolkit.createComposite(s1);
>     GridLayout glayout = new GridLayout(2,false);
>     glayout.marginWidth = glayout.marginHeight = 5;
>     glayout.verticalSpacing=5;
>     glayout.numColumns = 2;
>     client.setLayout(glayout);
>     
>     Table t = toolkit.createTable(client,SWT.SINGLE | SWT.FULL_SELECTION);
>     gd = new GridData(GridData.FILL_BOTH);
>     gd.horizontalIndent=2;
>     gd.heightHint = 20;
>     gd.widthHint = 100;
>     t.setLayoutData(gd);
>     t.setHeaderVisible(true);
>     t.setLinesVisible(true);
>     
>     Button b = toolkit.createButton(client, 
> Messages.getString("PartsBlock.add"), SWT.PUSH); //$NON-NLS-1$
>     gd = new GridData(GridData.VERTICAL_ALIGN_BEGINNING);
>     b.setLayoutData(gd);
>        
>         TableColumn amountTc = new TableColumn(t, SWT.RIGHT, 0);
>         amountTc.setText(Messages.getString("PartDetails.amount")); 
> //$NON-NLS-1$
>         amountTc.setWidth(50);
>         TableColumn unitTc = new TableColumn(t, SWT.LEFT, 1);
>         unitTc.setText(Messages.getString("PartDetails.unit")); 
> //$NON-NLS-1$
>         unitTc.setWidth(70);
>         TableColumn foodTc = new TableColumn(t, SWT.LEFT, 2);
>         foodTc.setText(Messages.getString("PartDetails.food")); 
> //$NON-NLS-1$
>         foodTc.setWidth(200);
>
>         TextCellEditor ce1 = new TextCellEditor(t);
>         ComboBoxCellEditor ce2 = new 
> ComboBoxCellEditor(t,UnitLoader.getInstance().getUnitsAsString(),SWT.DROP_DOWN|SWT.READ_ONLY); 
>
>         IngredientDialogCellEditor ce3 = new IngredientDialogCellEditor(t);
>
>     ingredientViewer = new TableViewer(t);
>     ingredientViewer.setContentProvider(new PartsContentProvider());
>     ingredientViewer.setColumnProperties(new String[] 
> {"amount","unit","food"});
>     ingredientViewer.setLabelProvider(new PartsLabelProvider());
>         ingredientViewer.setCellEditors(new CellEditor[] { ce1, ce2, ce3 
> });
>         ingredientViewer.setCellModifier(new IngredientCellModifier());
>
>     toolkit.paintBordersFor(s1);
>     toolkit.paintBordersFor(client);
>     s1.setClient(client);
>
>     final Section s2 = toolkit.createSection(parent, Section.EXPANDED| 
> Section.COMPACT | Section.TWISTIE);
>     s2.marginWidth = 10;
>     s2.setText("Steps");
>     s2.setDescription("Insert all the properties for one part of the 
> recipe");
>     s2.addExpansionListener(new IExpansionListener() {
>             public void expansionStateChanging(ExpansionEvent e) {
>             }
>
>             public void expansionStateChanged(ExpansionEvent e) {
>                 if (!(s2.isExpanded())) {
>                     parent.pack();
>                 }
>
>             }
>         });
>     gd = new GridData(GridData.FILL_BOTH);
>     gd.horizontalSpan = 1;
>     s2.setLayoutData(gd);
>     toolkit.createCompositeSeparator(s2);
>     Composite client2 = toolkit.createComposite(s2);
>     GridLayout glayout2 = new GridLayout();
>     glayout2.marginWidth = glayout2.marginHeight = 5;
>     glayout2.numColumns = 2;
>     client2.setLayout(glayout2);
>
>     gd = new GridData(GridData.FILL_BOTH);
>     gd.horizontalSpan=2;
>     steps = toolkit.createText(client2,"",SWT.MULTI | SWT.WRAP);
>         steps.setData(FormToolkit.KEY_DRAW_BORDER, 
> FormToolkit.TREE_BORDER);
>
>         steps.setLayoutData(gd);
>
>     toolkit.paintBordersFor(client2);
>     toolkit.paintBordersFor(s2);
>     s2.setClient(client2);
>     }
>
>     public void initialize(IManagedForm form) {
>         mform=form;
>     }
>
>     public void dispose() {
>     }
>
>     public boolean isDirty() {
>         return false;
>     }
>
>     public void commit(boolean onSave) {
>     }
>
>     public boolean setFormInput(Object input) {
>         return false;
>     }
>
>     public void setFocus() {
>     }
>
>     public boolean isStale() {
>         return false;
>     }
>
>     public void refresh() {
>     }
>
>     public void selectionChanged(IFormPart part, ISelection selection) {
>     IStructuredSelection ssel = (IStructuredSelection)selection;
>     if (ssel.size()==1) {
>         Part input = (Part)ssel.getFirstElement();
>         ingredientViewer.setInput(input);
>         steps.setText(getStepsAsString(input));
>     }
>     }
>
>     protected String getStepsAsString(Part part) {
>         String temp="";
>         log.debug("Amount of Steps: "+part.getSteps().size());
>         Iterator it = part.getSteps().iterator();
>
>         while (it.hasNext()) {
>             Step step = (Step)it.next();
>             log.debug("Step.text() = "+step.getText());
>             temp+=step.getText()+"\n\n";
>         }
>         return temp;
>     }
> }
>
> !ENTRY org.eclipse.ui.workbench 4 2 2005-07-27 22:31:39.656
> !MESSAGE Problems occurred when invoking code from plug-in: 
> "org.eclipse.ui.workbench".
> !STACK 0
> java.lang.NullPointerException
>     at org.eclipse.swt.widgets.Table.releaseWidget(Table.java:1705)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Widget.releaseResources(Widget.java:720)
>     at 
> org.eclipse.swt.widgets.Composite.releaseChildren(Composite.java:588)
>     at org.eclipse.swt.widgets.Composite.releaseWidget(Composite.java:593)
>     at org.eclipse.swt.widgets.Canvas.releaseWidget(Canvas.java:117)
>     at 
> org.eclipse.swt.widgets.Decorations.releaseWidget(Decorations.java:782)
>     at org.eclipse.swt.widgets.Shell.releaseWidget(Shell.java:868)
>     at org.eclipse.swt.widgets.Widget.dispose(Widget.java:382)
>     at org.eclipse.swt.widgets.Decorations.dispose(Decorations.java:441)
>     at org.eclipse.swt.widgets.Shell.dispose(Shell.java:499)
>     at org.eclipse.jface.window.Window.close(Window.java:321)
>     at 
> org.eclipse.jface.window.ApplicationWindow.close(ApplicationWindow.java:291) 
>
>     at 
> org.eclipse.ui.internal.WorkbenchWindow.hardClose(WorkbenchWindow.java:1403) 
>
>     at 
> org.eclipse.ui.internal.WorkbenchWindow.busyClose(WorkbenchWindow.java:646)
>     at 
> org.eclipse.ui.internal.WorkbenchWindow.access$0(WorkbenchWindow.java:627)
>     at 
> org.eclipse.ui.internal.WorkbenchWindow$2.run(WorkbenchWindow.java:728)
>     at 
> org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:69)
>     at 
> org.eclipse.ui.internal.WorkbenchWindow.close(WorkbenchWindow.java:726)
>     at org.eclipse.jface.window.WindowManager.close(WindowManager.java:108)
>     at org.eclipse.ui.internal.Workbench$11.run(Workbench.java:588)
>     at 
> org.eclipse.core.internal.runtime.InternalPlatform.run(InternalPlatform.java:1044) 
>
>     at org.eclipse.core.runtime.Platform.run(Platform.java:783)
>     at org.eclipse.ui.internal.Workbench.busyClose(Workbench.java:585)
>     at org.eclipse.ui.internal.Workbench.access$8(Workbench.java:522)
>     at org.eclipse.ui.internal.Workbench$13.run(Workbench.java:713)
>     at 
> org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:69)
>     at org.eclipse.ui.internal.Workbench.close(Workbench.java:711)
>     at org.eclipse.ui.internal.Workbench.close(Workbench.java:686)
>     at 
> org.eclipse.ui.internal.WorkbenchWindow.busyClose(WorkbenchWindow.java:643)
>     at 
> org.eclipse.ui.internal.WorkbenchWindow.access$0(WorkbenchWindow.java:627)
>     at 
> org.eclipse.ui.internal.WorkbenchWindow$2.run(WorkbenchWindow.java:728)
>     at 
> org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:69)
>     at 
> org.eclipse.ui.internal.WorkbenchWindow.close(WorkbenchWindow.java:726)
>     at 
> org.eclipse.jface.window.Window.handleShellCloseEvent(Window.java:727)
>     at org.eclipse.jface.window.Window$3.shellClosed(Window.java:674)
>     at 
> org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:159)
>     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.Decorations.closeWidget(Decorations.java:257)
>     at org.eclipse.swt.widgets.Decorations.WM_CLOSE(Decorations.java:1649)
>     at org.eclipse.swt.widgets.Control.windowProc(Control.java:3040)
>     at 
> org.eclipse.swt.widgets.Decorations.windowProc(Decorations.java:1582)
>     at org.eclipse.swt.widgets.Display.windowProc(Display.java:3706)
>     at org.eclipse.swt.internal.win32.OS.DefWindowProcW(Native Method)
>     at org.eclipse.swt.internal.win32.OS.DefWindowProc(OS.java:1651)
>     at org.eclipse.swt.widgets.Shell.callWindowProc(Shell.java:410)
>     at org.eclipse.swt.widgets.Control.windowProc(Control.java:3123)
>     at 
> org.eclipse.swt.widgets.Decorations.windowProc(Decorations.java:1582)
>     at org.eclipse.swt.widgets.Display.windowProc(Display.java:3706)
>     at org.eclipse.swt.internal.win32.OS.DefWindowProcW(Native Method)
>     at org.eclipse.swt.internal.win32.OS.DefWindowProc(OS.java:1651)
>     at org.eclipse.swt.widgets.Shell.callWindowProc(Shell.java:410)
>     at org.eclipse.swt.widgets.Control.windowProc(Control.java:3123)
>     at 
> org.eclipse.swt.widgets.Decorations.windowProc(Decorations.java:1582)
>     at org.eclipse.swt.widgets.Display.windowProc(Display.java:3706)
>     at org.eclipse.swt.internal.win32.OS.DispatchMessageW(Native Method)
>     at org.eclipse.swt.internal.win32.OS.DispatchMessage(OS.java:1656)
>     at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2711)
>     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 de.beecook.core.BeeCookApplication.run(BeeCookApplication.java:39)
>     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)