import de.taimos.gpsd4java.backend.GPSdEndpoint;

/**

* Copyright 2011 Thorsten Höger, Taimos GmbH

*

* Licensed under the Apache License, Version 2.0 (the "License"); you may not

* use this file except in compliance with the License. You may obtain a copy of

* the License at

*

* http://www.apache.org/licenses/LICENSE-2.0

*

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT

* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the

* License for the specific language governing permissions and limitations under

* the License.

*/

package de.taimos.gpsd4java.api;

import de.taimos.gpsd4java.backend.GISTool;

import de.taimos.gpsd4java.types.TPVObject;

/**

*

* created: 19.01.2011

*

*/

public abstract class DistanceListener extends ObjectListener {

private TPVObject lastPosition;

private double threshold;

/**

* @param threshold the threshold to fire in kilometers

*/

public DistanceListener(double threshold) {

this.threshold = threshold;

}

@Override

public void handleTPV(TPVObject tpv) {

if ((this.lastPosition == null) || (GISTool.getDistance(tpv, this.lastPosition) > this.threshold)) {

this.lastPosition = tpv;

this.handleLocation(tpv);

}

}

protected abstract void handleLocation(TPVObject tpv);

}

package de.taimos.gpsd4java.backend;

import de.taimos.gpsd4java.types.TPVObject;

/**

* @author thoeger

*

*/

public class GISTool {

/**

* @param c1

* @param c2

* @return distance in kilometers

*/

public static double getDistance(final TPVObject c1, final TPVObject c2) {

return GISTool.getDistance(c1.getLongitude(), c2.getLongitude(), c1.getLatitude(), c2.getLatitude());

}

/**

* @param x1

* @param x2

* @param y1

* @param y2

* @return distance in kilometers

*/

public static double getDistance(double x1, double x2, double y1, double y2) {

x1 = x1 * (Math.PI / 180);

x2 = x2 * (Math.PI / 180);

y1 = y1 * (Math.PI / 180);

y2 = y2 * (Math.PI / 180);

final double dlong = x1 - x2;

final double dlat = y1 - y2;

final double a = Math.pow(Math.sin(dlat / 2), 2) + Math.cos(y1) * Math.cos(y2) * Math.pow(Math.sin(dlong / 2), 2);

final double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));

// Earth radius in kilometers

return 6367 * c;

}

}

package de.taimos.gpsd4java.backend;

package de.taimos.gpsd4java.backend;

package de.taimos.gpsd4java.backend;