com.phloc.commons.compare.ComparatorStringLongestFirst Maven / Gradle / Ivy
/**
* Copyright (C) 2006-2015 phloc systems
* http://www.phloc.com
* office[at]phloc[dot]com
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.phloc.commons.compare;
import java.util.Comparator;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
/**
* A special comparator that sorts String, but the longest strings come first.
* For all strings with an equal length, they are sorted in regular,
* non-collated order.
*
* @author Boris Gregorcic
* @author Philip Helger
*/
public class ComparatorStringLongestFirst extends AbstractComparator
{
private static final long serialVersionUID = 542245909907407229L;
/**
* Comparator without a nested comparator.
*/
public ComparatorStringLongestFirst ()
{
super ();
}
/**
* Comparator with a nested comparator.
*
* @param aNestedComparator
* The nested comparator to be invoked, when the main comparison
* resulted in 0.
*/
public ComparatorStringLongestFirst (@Nullable final Comparator aNestedComparator)
{
super (aNestedComparator);
}
@Override
protected int mainCompare (@Nonnull final String sElement1, @Nonnull final String sElement2)
{
// The longer, the earlier in the results
int ret = CompareUtils.compare (sElement2.length (), sElement1.length ());
if (ret == 0)
{
// Important to compare the content as well because with ret==0,
// elements would eventually be removed (e.g. from a TreeMap)
ret = sElement1.compareTo (sElement2);
}
return ret;
}
}