PlotSquared/PlotSquared/src/main/java/com/intellectualcrafters/plot/PlotId.java

////////////////////////////////////////////////////////////////////////////////////////////////////
// PlotSquared - A plot manager and world generator for the Bukkit API                             /
// Copyright (c) 2014 IntellectualSites/IntellectualCrafters                                       /
//                                                                                                 /
// This program is free software; you can redistribute it and/or modify                            /
// it under the terms of the GNU General Public License as published by                            /
// the Free Software Foundation; either version 3 of the License, or                               /
// (at your option) any later version.                                                             /
//                                                                                                 /
// This program 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 General Public License                               /
// along with this program; if not, write to the Free Software Foundation,                         /
// Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA                               /
//                                                                                                 /
// You can contact us via: support@intellectualsites.com                                           /
////////////////////////////////////////////////////////////////////////////////////////////////////

package com.intellectualcrafters.plot;

public class PlotId {

    /**
     * Get a Plot Id based on a string
     *
     * @param string to create id from
     * @return null if the string is invalid
     */
    public static PlotId fromString(final String string) {
        int x, y;
        String[] parts = string.split(";");
        if (parts.length < 2)
            return null;
        try {
            x = Integer.parseInt(parts[0]);
            y = Integer.parseInt(parts[1]);
        } catch (Exception e) {
            return null;
        }
        return new PlotId(x, y);
    }

    /**
     * x value
     */
    public Integer x;
    /**
     * y value
     */
    public Integer y;

    /**
     * PlotId class (PlotId x,y values do not correspond to Block locations)
     *
     * @param x The plot x coordinate
     * @param y The plot y coordinate
     */
    public PlotId(final int x, final int y) {
        this.x = x;
        this.y = y;
    }

    @Override
    public boolean equals(final Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        final PlotId other = (PlotId) obj;
        return ((this.x == other.x) && (this.y == other.y));
    }

    @Override
    public String toString() {
        return this.x + ";" + this.y;
    }

    @Override
    public int hashCode() {
        if (x >= 0) {
            if (y >= 0) {
                return x * x + 3 * x + 2 * x * y + y + y * y;
            } else {
                int y1 = -y;
                return x * x + 3 * x + 2 * x * y1 + y1 + y1 * y1 + 1;
            }
        } else {
            int x1 = -x;
            if (y >= 0) {
                return -(x1 * x1 + 3 * x1 + 2 * x1 * y + y + y * y);
            } else {
                int y1 = -y;
                return -(x1 * x1 + 3 * x1 + 2 * x1 * y1 + y1 + y1 * y1 + 1);
            }
        }
    }
}