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
return false;
	}
	/**
	 * Returns the <code>IShowInSource</code> for this view.
	 */
	protected IShowInSource getShowInSource() {
		return new IShowInSource() {
			public ShowInContext getShowInContext() {
				return new ShowInContext(
					getViewer().getInput(),
					getViewer().getSelection());
			}
		};
	}
	/**
	 * @see IResourceNavigator#setLinkingEnabled(boolean)
	 * @since 2.1
	 */
	public void setLinkingEnabled(boolean enabled) {
		fLinkingEnabled= enabled;
		PreferenceConstants.getPreferenceStore().setValue(PreferenceConstants.LINK_PACKAGES_TO_EDITOR, enabled);
		if (enabled) {
			IEditorPart editor = getSite().getPage().getActiveEditor();
			if (editor != null) {
				editorActivated(editor);
			}
		}
	}
}