/*
 * The JTS Topology Suite is a collection of Java classes that
 * implement the fundamental operations required to validate a given
 * geo-spatial data set to a known topological specification.
 *
 * Copyright (C) 2001 Vivid Solutions
 *
 * This 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 2.1 of the License, or (at your option) any later version.
 *
 * This 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 this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * For more information, contact:
 *
 *     Vivid Solutions
 *     Suite #1A
 *     2328 Government Street
 *     Victoria BC  V8T 5G5
 *     Canada
 *
 *     (250)385-6040
 *     www.vividsolutions.com
 */
package com.revolsys.geometry.model.impl;

import com.revolsys.geometry.model.Geometry;
import com.revolsys.geometry.model.LinearRing;
import com.revolsys.geometry.model.Polygon;
import com.revolsys.util.Exceptions;

/**
 * Represents a polygon with linear edges, which may include holes.
 * The outer boundary (shell)
 * and inner boundaries (holes) of the polygon are represented by {@link LinearRing}s.
 * The boundary rings of the polygon may have any orientation.
 * Polygons are closed, simple geometries by definition.
 * <p>
 * The polygon model conforms to the assertions specified in the
 * <A HREF="http://www.opengis.org/techno/specs.htm">OpenGIS Simple Features
 * Specification for SQL</A>.
 * <p>
 * A <code>Polygon</code> is topologically valid if and only if:
 * <ul>
 * <li>the coordinates which define it are valid coordinates
 * <li>the linear rings for the shell and holes are valid
 * (i.e. are closed and do not self-intersect)
 * <li>holes touch the shell or another hole at at most one point
 * (which implies that the rings of the shell and holes must not cross)
 * <li>the interior of the polygon is connected,
 * or equivalently no sequence of touching holes
 * makes the interior of the polygon disconnected
 * (i.e. effectively split the polygon into two pieces).
 * </ul>
 *
 *@version 1.7
 */
public abstract class AbstractPolygon implements Polygon {
  private static final long serialVersionUID = -3494792200821764533L;

  public AbstractPolygon() {
  }

  /**
   * Creates and returns a full copy of this {@link Polygon} object.
   * (including all coordinates contained by it).
   *
   * @return a clone of this instance
   */
  @Override
  public Polygon clone() {
    try {
      return (Polygon)super.clone();
    } catch (final CloneNotSupportedException e) {
      throw Exceptions.wrap(e);
    }
  }

  /**
   * Tests whether this geometry is structurally and numerically equal
   * to a given <code>Object</code>.
   * If the argument <code>Object</code> is not a <code>Geometry</code>,
   * the result is <code>false</code>.
   * Otherwise, the result is computed using
   * {@link #equals(2,Geometry)}.
   * <p>
   * This method is provided to fulfill the Java contract
   * for value-based object equality.
   * In conjunction with {@link #hashCode()}
   * it provides semantics which are most useful
   * for using
   * <code>Geometry</code>s as keys and values in Java collections.
   * <p>
   * Note that to produce the expected result the input geometries
   * should be in normal form.  It is the caller's
   * responsibility to perform this where required
   * (using {@link Geometry#norm()
   * or {@link #normalize()} as appropriate).
   *
   * @param other the Object to compare
   * @return true if this geometry is exactly equal to the argument
   *
   * @see #equals(2,Geometry)
   * @see #hashCode()
   * @see #norm()
   * @see #normalize()
   */
  @Override
  public boolean equals(final Object other) {
    if (other instanceof Geometry) {
      final Geometry geometry = (Geometry)other;
      return equals(2, geometry);
    } else {
      return false;
    }
  }

  /**
   * Gets a hash code for the Geometry.
   *
   * @return an integer value suitable for use as a hashcode
   */

  @Override
  public int hashCode() {
    return getBoundingBox().hashCode();
  }

  @Override
  public String toString() {
    return toEwkt();
  }
}