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 package org.infinispan.commons.util;
 
 import java.util.Map;
 import java.util.Set;
A helper that efficiently duplicates known object types.

Author(s):
(various)
Since:
4.0
public class ObjectDuplicator {
   @SuppressWarnings("unchecked")
   public static <K, V> Map<K, V> duplicateMap(Map<K, V> original) {
      if (original instanceof FastCopyHashMap)
         return (Map<K, V>) ((FastCopyHashMap<K, V>) original).clone();
      if (original instanceof HashMap)
         return (Map<K, V>) ((HashMap<K, V>) original).clone();
      if (original instanceof TreeMap)
         return (Map<K, V>) ((TreeMap<K, V>) original).clone();
      if (original.getClass().equals(InfinispanCollections.emptyMap().getClass()))
         return InfinispanCollections.emptyMap();
      if (original.getClass().equals(Collections.emptyMap().getClass()))
         return Collections.emptyMap();
      if (original.getClass().equals(Collections.singletonMap("""").getClass())) {
         Map.Entry<K, V> e = original.entrySet().iterator().next();
         return Collections.singletonMap(e.getKey(), e.getValue());
      }
      return attemptClone(original);
   }
   @SuppressWarnings("unchecked")
   public static <E> Set<E> duplicateSet(Set<E> original) {
      if (original instanceof HashSet)
         return (Set<E>) ((HashSet<E>) original).clone();
      if (original instanceof TreeSet)
         return (Set<E>) ((TreeSet<E>) original).clone();
      if (original instanceof FastCopyHashMap.EntrySet || original instanceof FastCopyHashMap.KeySet)
         return new HashSet<E>(original);
      if (original.getClass().equals(InfinispanCollections.emptySet().getClass()))
         return InfinispanCollections.emptySet();
      if (original.getClass().equals(Collections.emptySet().getClass()))
         return Collections.emptySet();
      if (original.getClass().equals(Collections.singleton("").getClass()))
         return Collections.singleton(original.iterator().next());
      if (original.getClass().getSimpleName().contains("$"))
         return new HashSet<E>(original);
      return attemptClone(original);
   }
   @SuppressWarnings("unchecked")
   public static <E> Collection<E> duplicateCollection(Collection<E> original) {
      if (original instanceof HashSet)
         return (Set<E>) ((HashSet<E>) original).clone();
      if (original instanceof TreeSet)
         return (Set<E>) ((TreeSet<E>) original).clone();
      return attemptClone(original);
   }
   @SuppressWarnings("unchecked")
   private static <T> T attemptClone(T source) {
      if (source instanceof Cloneable) {
         try {
            return (T) source.getClass().getMethod("clone").invoke(source);
         }
         catch (Exception e) {
         }
      }
      return null;
   }
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