Bug 125144 Clicking Show Project in Package Explorer results in exception
Clicking Show Project in Code model results in exception in DOS box === Steps to Reproduce: Create a Java project Open the Package Explorer Click the View menu Show - Projects. (This actually is a radio group menu item. It is by default selected, so clicking it again should have no effect) === Observed behaviour: Dos box: Unhandled event loop exception Reason: java.lang.NullPointerException See .log file (will be attached) === Expected behaviour: No exception === Reproducibility: yes
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
/**
 	 * Returns the TreeViewer.
 	 */
	public TreeViewer getTreeViewer() {
		return fViewer;
	}
	
	boolean isExpandable(Object element) {
		if (fViewer == null)
			return false;
		return fViewer.isExpandable(element);
	}
	void setWorkingSetLabel(String workingSetName) {
		fWorkingSetLabel= workingSetName;
	}
	
	/**
	 * Updates the title text and title tool tip.
	 * Called whenever the input of the viewer changes.
	 */ 
	void updateTitle() {		
		Object input= fViewer.getInput();
		if (input == null
			|| (input instanceof IJavaModel)) {
			setContentDescription(""); 
			setTitleToolTip(""); 
		} else {
			String inputText= JavaElementLabels.getTextLabel(input, AppearanceAwareLabelProvider.DEFAULT_TEXTFLAGS);
			setContentDescription(inputText);