PointConverter.java

/*****************************************************************************
 *  Limpet - the Lightweight InforMation ProcEssing Toolkit
 *  http://limpet.info
 *
 *  (C) 2015-2016, Deep Blue C Technologies Ltd
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the Eclipse Public License v1.0
 *  (http://www.eclipse.org/legal/epl-v10.html)
 *
 *  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.
 *****************************************************************************/
package info.limpet.data.persistence.xml;

import info.limpet.data.operations.spatial.GeoSupport;

import java.awt.geom.Point2D;

import com.thoughtworks.xstream.converters.Converter;
import com.thoughtworks.xstream.converters.MarshallingContext;
import com.thoughtworks.xstream.converters.UnmarshallingContext;
import com.thoughtworks.xstream.io.HierarchicalStreamReader;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;

public class PointConverter implements Converter
{

  public PointConverter()
  {
  }

  @SuppressWarnings("rawtypes")
  @Override
  public boolean canConvert(Class type)
  {
    return Point2D.class.isAssignableFrom(type);
  }

  @Override
  public void marshal(Object source, HierarchicalStreamWriter writer,
      MarshallingContext context)
  {
    Point2D point = (Point2D) source;
    writer.startNode("lat");
    String value = Double.toString(point.getY());
    writer.setValue(value);
    writer.endNode();
    writer.startNode("lon");
    value = Double.toString(point.getX());
    writer.setValue(value);
    writer.endNode();
  }

  @Override
  public Object unmarshal(HierarchicalStreamReader reader,
      UnmarshallingContext context)
  {
    double lat = 0, lon = 0;
    while (reader.hasMoreChildren())
    {
      reader.moveDown();
      if ("lat".equals(reader.getNodeName()))
      {
        lat = new Double(reader.getValue()).doubleValue();
      }
      else if ("lon".equals(reader.getNodeName()))
      {
        lon = new Double(reader.getValue()).doubleValue();
      }
      reader.moveUp();
    }
    Point2D point = GeoSupport.getCalculator().createPoint(lon, lat);
    return point;
  }

}