Bug 81877 Package explorer forgets active working set [package explorer]
3.1 M4 1. open pkg explorer. 2. select a working set, pkg explorer updates and filters out projects. 3. close pkg explorer. 4. open package explorer again and the working set is no longer applied. This used to work.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
}
	
	/**
	 * Returns the package explorer part of the active perspective. If 
	 * there isn't any package explorer part <code>null</code> is returned.
	 */
	public static PackageExplorerPart getFromActivePerspective() {
		IWorkbenchPage activePage= JavaPlugin.getActivePage();
		if (activePage == null)
			return null;
		IViewPart view= activePage.findView(VIEW_ID);
		if (view instanceof PackageExplorerPart)
			return (PackageExplorerPart)view;
		return null;	
	}
	
	/**
	 * Makes the package explorer part visible in the active perspective. If there
	 * isn't a package explorer part registered <code>null</code> is returned.
	 * Otherwise the opened view part is returned.
	 */
	public static PackageExplorerPart openInActivePerspective() {
		try {
			return (PackageExplorerPart)JavaPlugin.getActivePage().showView(VIEW_ID);
		} catch(PartInitException pe) {
			return null;
		}
	} 
		
	 public void dispose() {