DistanceComparator.java

/*
 * Copyright (c) [2016] [ <ether.camp> ]
 * This file is part of the ethereumJ library.
 *
 * The ethereumJ library 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 3 of the License, or
 * (at your option) any later version.
 *
 * The ethereumJ library 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 the ethereumJ library. If not, see <http://www.gnu.org/licenses/>.
 */
package org.ethereum.net.rlpx.discover.table;

import java.util.Comparator;

/**
 * Created by kest on 5/26/15.
 */
public class DistanceComparator implements Comparator<NodeEntry>  {
    byte[] targetId;

    DistanceComparator(byte[] targetId) {
        this.targetId = targetId;
    }

    @Override
    public int compare(NodeEntry e1, NodeEntry e2) {
        int d1 = NodeEntry.distance(targetId, e1.getNode().getId());
        int d2 = NodeEntry.distance(targetId, e2.getNode().getId());

        if (d1 > d2) {
            return 1;
        } else if (d1 < d2) {
            return -1;
        } else {
            return 0;
        }
    }
}