Bug 97523 [Import/Export] Get overwrite prompt before no resources selected prompt
3.1 RC1 - File > Export > Archive - clear any selected resources - enter an archive file name where the file already exists - Finish - it prompts to overwrite the file; choose Yes - it says "There are no resources currently selected for export" (OK) Should get the "no resources" prompt first, and not bother with the second one. Should check the other export wizards too.
bundles/org.eclipse.ui.ide/extensions/org/eclipse/ui/dialogs/WizardExportResourcesPage.java
*   type: <code>String</code>)
     */
    protected List getTypesToExport() {
        return selectedTypes;
    }
    /**
     * Returns this page's collection of currently-specified resources to be 
     * exported. This returns both folders and files - for just the files use
     * getSelectedResources.
     *
     * @return a collection of resources currently selected 
     * for export (element type: <code>IResource</code>)
     */
    protected List getWhiteCheckedResources() {
        return this.resourceGroup.getAllWhiteCheckedItems();
    }
    /**
     * Queries the user for the types of resources to be exported and selects
     * them in the checkbox group.
     */
    protected void handleTypesEditButtonPressed() {
        Object[] newSelectedTypes = queryResourceTypesToExport();
        if (newSelectedTypes != null) { 
            this.selectedTypes = new ArrayList(newSelectedTypes.length);
            for (int i = 0; i < newSelectedTypes.length; i++) {
                this.selectedTypes.add(newSelectedTypes[i]);
            }
            setupSelectionsBasedOnSelectedTypes();
        }
    }