/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later.
* See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
*/
package org.hibernate.envers.internal.tools;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.hibernate.envers.tools.Pair;
import org.hibernate.internal.util.compare.EqualsHelper;
/**
* @author Adam Warski (adam at warski dot org)
* @author HernпїЅn Chanfreau
* @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
* @author Chris Cranford
*/
public abstract class Tools {
public static <K, V> Map<K, V> newHashMap() {
return new HashMap<>();
}
public static <E> Set<E> newHashSet() {
return new HashSet<>();
}
public static <K, V> Map<K, V> newLinkedHashMap() {
return new LinkedHashMap<>();
}
/**
* @deprecated (since 5.2), use {@link EqualsHelper#areEqual(Object, Object)}.
*/
@Deprecated
public static boolean objectsEqual(Object obj1, Object obj2) {
// HHH-10734
// Delegates to core's EqualsHelper to support array and non-array types
return EqualsHelper.areEqual( obj1, obj2 );
}
public static <T> List<T> iteratorToList(Iterator<T> iter) {
final List<T> ret = new ArrayList<>();
while ( iter.hasNext() ) {
ret.add( iter.next() );
}
return ret;
}
public static <X> List<X> collectionToList(Collection<X> collection) {
if ( collection instanceof List ) {
return (List<X>) collection;
}
else {
List<X> list = new ArrayList<>();
list.addAll( collection );
return list;
}
}
public static boolean iteratorsContentEqual(Iterator iter1, Iterator iter2) {
while ( iter1.hasNext() && iter2.hasNext() ) {
if ( !iter1.next().equals( iter2.next() ) ) {
return false;
}
}
//noinspection RedundantIfStatement
if ( iter1.hasNext() || iter2.hasNext() ) {
return false;
}
return true;
}
/**
* Transforms a list of arbitrary elements to a list of index-element pairs.
*
* @param list List to transform.
*
* @return A list of pairs: ((0, element_at_index_0), (1, element_at_index_1), ...)
*/
public static <T> List<Pair<Integer, T>> listToIndexElementPairList(List<T> list) {
final List<Pair<Integer, T>> ret = new ArrayList<>();
final Iterator<T> listIter = list.iterator();
for ( int i = 0; i < list.size(); i++ ) {
ret.add( Pair.make( i, listIter.next() ) );
}
return ret;
}
}