r this,
{@link org.openide.util.lookup.AbstractLookup AbstractLookup }
is recommended as it is easiest to use.

<p>The simplest way to use <code>AbstractLookup</code> is to use its
public constructor (in which case you need not subclass it). Here you
provide an
{@link org.openide.util.lookup.AbstractLookup.Content AbstractLookup.Content }
object which you have created and hold on to privately, and which
keeps track of instances and permits them to be registered and
deregistered. Often

{@link org.openide.ut