package api;

 import java.util.ArrayList;

 import java.util.Collection;

 import java.util.Iterator;

 import java.util.Set;

 /** Factory to create various types of lookup instances.

  *

  * @author Jaroslav Tulach <jtulach@netbeans.org>

  * @version 2.0

  */

 public final class Lookups {

     private Lookups() {

     }

     public static Lookup fixed(final Object... instances) {

         return new Lookup() {

             @Override

             <T> Iterator<T> doLookup(Class<T> clazz) {

                 ArrayList<T> result = new ArrayList<T>();

                 for (Object obj : instances) {

                     if (clazz.isInstance(obj)) {

                         result.add(clazz.cast(obj));

                     }

                 }

                 return result.iterator();

             }

         };

     }

     public static Lookup dynamic(final Dynamic provider) {

         return new Lookup() {

             @Override

             <T> Iterator<T> doLookup(Class<T> clazz) {

                 ArrayList<T> result = new ArrayList<T>();

                 provider.computeInstances(clazz, result);

                 return result.iterator();

             }

         };

     }

     public interface Dynamic {

         public <T> void computeInstances(Class<T> requestedType, Collection<? super T> addInstancesTo);

     }

 }