/*
* JBoss, Home of Professional Open Source
* Copyright 2009 Red Hat Inc. and/or its affiliates and other
* contributors as indicated by the @author tags. All rights reserved.
* See the copyright.txt in the distribution for a full listing of
* individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.infinispan.util;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.TreeSet;
/**
* A helper that efficiently duplicates known object types.
*
* @author (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(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(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;
}
}