Bug 32224 [Show In]Back-linking doesn't work for .class files in jars
Build 20030218 1. Enable back-linking in Package Explorer 2. Open Object (in rt.jar) Observe: An editor on Object.class opens (it shows the attached source). However Object.class is not shown in Package Explorer Note that Alt-Shift-s->Package Explorer doesn't work either.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
}
	
	/**
	 * Answer the property defined by key.
	 */
	public Object getAdapter(Class key) {
		if (key.equals(ISelectionProvider.class))
			return fViewer;
		if (key == IShowInSource.class) {
			return getShowInSource();
		}
		if (key == IShowInTargetList.class) {
			return new IShowInTargetList() {
				public String[] getShowInTargetIds() {
					return new String[] { IPageLayout.ID_RES_NAV };
				}
			};
		}
		return super.getAdapter(key);
	}
	/**
	 * Returns the tool tip text for the given element.
	 */
	String getToolTipText(Object element) {
		String result;
		if (!(element instanceof IResource)) {
			result= JavaElementLabels.getTextLabel(element, AppearanceAwareLabelProvider.DEFAULT_TEXTFLAGS);		
		} else {
			IPath path= ((IResource) element).getFullPath();
			if (path.isRoot()) {