SquirrelJME/SquirrelJME

// -*- Mode: Java; indent-tabs-mode: t; tab-width: 4 -*-
// ---------------------------------------------------------------------------
// Multi-Phasic Applications: SquirrelJME
//     Copyright (C) Stephanie Gawroriski <xer@multiphasicapps.net>
// ---------------------------------------------------------------------------
// SquirrelJME is under the Mozilla Public License Version 2.0.
// See license.mkd for licensing and copyright information.
// ---------------------------------------------------------------------------

package java.util;

import cc.squirreljme.runtime.cldc.debug.Debugging;

/**
 * Reverses the operation of a given {@link Comparator}, used by
 * {@link Collections#reverseOrder(Comparator)}.
 *
 * @param <T> The type to compare.
 * @see Collections#reverseOrder(Comparator) 
 * @since 2022/07/29
 */
final class __ReverseComparator__<T>
    implements Comparator<T>
{
    /** The comparator to reverse. */
    final Comparator<T> _comparator;
    
    /**
     * Initializes the reverse comparator.
     * 
     * @param __comp The comparator to reverse.
     * @throws NullPointerException On null arguments.
     * @since 2022/07/29
     */
    __ReverseComparator__(Comparator<T> __comp)
        throws NullPointerException
    {
        if (__comp == null)
            throw new NullPointerException("NARG");
        
        this._comparator = __comp;
    }
    
    /**
     * {@inheritDoc}
     * @since 2022/07/29
     */
    @Override
    public int compare(T __a, T __b)
    {
        // Negation makes it so earlier items are later, equals stay the same
        return -this._comparator.compare(__a, __b);
    }
}