DWR推送数据

package developerworks.jetty6.gpstracker; import java.util.*; /** * Generates a random walk */ public class RandomWalkGenerator implements Runnable { private static RandomWalkGenerator instance = new RandomWalkGenerator(); private Set<CoordListener> listeners = new HashSet<CoordListener>(); private GpsCoord currentCoord; private RandomWalkGenerator() { currentCoord = new GpsCoord(51.517476f,-0.086603f); new Thread(this).start(); } public static RandomWalkGenerator getInstance() { return instance; } public void run() { try { while (true) { int sleepMillis = 5000 + (int)(Math.random()*8000d); Thread.sleep(sleepMillis); dispatchUpdate(generateNextCoord()); } } catch (Exception e) { throw new RuntimeException(e); } } public void addListener(CoordListener listener) { synchronized(listeners) { listeners.add(listener); } } private void dispatchUpdate(GpsCoord coord) { synchronized(listeners) { for (CoordListener listener : listeners) { listener.onCoord(coord); } } } private GpsCoord generateNextCoord() { double dist = Math.random() * 0.002; double angle = Math.random() * 2d * Math.PI; float lat = currentCoord.getLatitude() + (float)(dist * Math.cos(angle)); float lng = currentCoord.getLongitude() + (float)(dist * Math.sin(angle)); currentCoord = new GpsCoord(lat,lng); return currentCoord; } }