Bug 8476 JAR Packager: Make main class field editable
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/jarpackager/JarManifestWizardPage.java
* 
	 * @param packageFragments the package fragments
	 * @return a new selection dialog
	 */
	protected SelectionDialog createPackageDialog(Set packageFragments) {
		List packages= new ArrayList(packageFragments.size());
		for (Iterator iter= packageFragments.iterator(); iter.hasNext();) {
			IPackageFragment fragment= (IPackageFragment)iter.next();
			boolean containsJavaElements= false;
			int kind;
			try {
				kind= fragment.getKind();
				containsJavaElements= fragment.getChildren().length > 0;
			} catch (JavaModelException ex) {
				ExceptionHandler.handle(ex, getContainer().getShell(), JarPackagerMessages.getString("JarManifestWizardPage.error.jarPackageWizardError.title"), JarPackagerMessages.getFormattedString("JarManifestWizardPage.error.jarPackageWizardError.message", fragment.getElementName())); 
				continue;
			}
			if (kind != IPackageFragmentRoot.K_BINARY && containsJavaElements)
				packages.add(fragment);
		}
		JavaElementContentProvider cp= new JavaElementContentProvider() {
			public boolean hasChildren(Object element) {
				
				return !(element instanceof IPackageFragment) && super.hasChildren(element);
			}
		};
		ElementTreeSelectionDialog dialog= new ElementTreeSelectionDialog(getContainer().getShell(), new JavaElementLabelProvider(JavaElementLabelProvider.SHOW_DEFAULT), cp);
		dialog.setDoubleClickSelects(false);
		dialog.setInput(JavaCore.create(JavaPlugin.getDefault().getWorkspace().getRoot()));
		dialog.addFilter(new EmptyInnerPackageFilter());