Bug 35265 NPE in classpath variables page
Build: I-20030317 I was switching back and forth between target platform and classpath variables preference pages, changing values on target platform page and seeing if changes are reflected on classpath variables page. At some point, I got the following null pointer: java.lang.NullPointerException at org.eclipse.jdt.internal.ui.wizards.buildpaths.CPVariableElementLabelProvider.ge tImage(CPVariableElementLabelProvider.java:55) at org.eclipse.jface.viewers.TableViewer.doUpdateItem(TableViewer.java:202) at org.eclipse.jface.viewers.StructuredViewer$UpdateItemSafeRunnable.run (StructuredViewer.java:119) at org.eclipse.core.internal.runtime.InternalPlatform.run (InternalPlatform.java:867) at org.eclipse.core.runtime.Platform.run(Platform.java:413) at org.eclipse.jface.viewers.StructuredViewer.updateItem (StructuredViewer.java:1271) at org.eclipse.jface.viewers.TableViewer.internalRefresh(TableViewer.java:454) at org.eclipse.jface.viewers.TableViewer.internalRefresh(TableViewer.java:431) at org.eclipse.jface.viewers.StructuredViewer$7.run(StructuredViewer.java:861) at org.eclipse.jface.viewers.StructuredViewer.preservingSelection (StructuredViewer.java:801) at org.eclipse.jface.viewers.StructuredViewer.refresh(StructuredViewer.java:859) at org.eclipse.jface.viewers.StructuredViewer.refresh(StructuredViewer.java:821) at org.eclipse.jdt.internal.ui.wizards.dialogfields.ListDialogField.refresh (ListDialogField.java:739) at org.eclipse.jdt.internal.ui.wizards.buildpaths.VariableBlock.refresh (VariableBlock.java:406) at org.eclipse.jdt.internal.ui.preferences.ClasspathVariablesPreferencePage.setVisi ble(ClasspathVariablesPreferencePage.java:80) at org.eclipse.jface.preference.PreferenceDialog.showPage (PreferenceDialog.java:1064) at org.eclipse.jface.preference.PreferenceDialog$9.run (PreferenceDialog.java:496)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/VariableBlock.java
public void dialogFieldChanged(DialogField field) {
		}
	
	}
	
	private boolean containsReserved(List selected) {
		for (int i= selected.size()-1; i >= 0; i--) {
			if (((CPVariableElement)selected.get(i)).isReserved()) {
				return true;
			}
		}
		return false;
	}
	
	private static void addAll(Object[] objs, Collection dest) {
		for (int i= 0; i < objs.length; i++) {
			dest.add(objs[i]);
		}
	}
	private void doSelectionChanged(DialogField field) {
		List selected= fVariablesList.getSelectedElements();
		boolean isSingleSelected= selected.size() == 1;
		boolean containsReserved= containsReserved(selected);
		
		
		fVariablesList.enableButton(1, isSingleSelected && !containsReserved);