ComparableIntegerDivision.java

/*
 * Aphelion
 * Copyright (c) 2013  Joris van der Wel
 * 
 * This file is part of Aphelion
 * 
 * Aphelion is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, version 3 of the License.
 * 
 * Aphelion 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License
 * along with Aphelion.  If not, see <http://www.gnu.org/licenses/>.
 * 
 * In addition, the following supplemental terms apply, based on section 7 of
 * the GNU Affero General Public License (version 3):
 * a) Preservation of all legal notices and author attributions
 * b) Prohibition of misrepresentation of the origin of this material, and
 * modified versions are required to be marked in reasonable ways as
 * different from the original version (for example by appending a copyright notice).
 * 
 * Linking this library statically or dynamically with other modules is making a
 * combined work based on this library. Thus, the terms and conditions of the
 * GNU Affero General Public License cover the whole combination.
 * 
 * As a special exception, the copyright holders of this library give you 
 * permission to link this library with independent modules to produce an 
 * executable, regardless of the license terms of these independent modules,
 * and to copy and distribute the resulting executable under terms of your 
 * choice, provided that you also meet, for each linked independent module,
 * the terms and conditions of the license of that module. An independent
 * module is a module which is not derived from or based on this library.
 */

package aphelion.shared.swissarmyknife;

/**
 *
 * @author Joris
 */
public final class ComparableIntegerDivision implements Comparable<ComparableIntegerDivision>
{
        public long div;
        public long mod; // modulo, but with the same sign as div

        public ComparableIntegerDivision()
        {
        }
        
        public ComparableIntegerDivision(long dividend, long divisor)
        {
                calculate(dividend, divisor);
        }
        
        public void calculate(long dividend, long divisor)
        {
                if (dividend == Long.MIN_VALUE && divisor == -1) { dividend++; }
                
                div = dividend / divisor; // exception if divisor is zero, which is fine
                mod = dividend - divisor * div;
                if (divisor < 0) mod = -mod;
        }
        
        public void set(ComparableIntegerDivision o)
        {
                div = o.div;
                mod = o.mod;
        }

        @Override
        public String toString()
        {
                return div + ", " + mod;
        }
        
        @Override
        public int compareTo(ComparableIntegerDivision o)
        {
                if (div == o.div)
                {
                        return Long.compare(mod, o.mod);
                }
                else
                {
                        return Long.compare(div, o.div);
                }
        }
}