Certainly. Certain parts will be missing, but here it is. Search for ***
to find the place where the problem occurs.

public class RouteAsyncTest extends TestCase {
    private final int START_PORT = 4440;
    private DHTImpl node1 = null;
    private DHTImpl node2 = null;
    private ConnectionManager cm1 = null;
    private ConnectionManager cm2 = null;
    private AppHandler app1 = null;
    private AppHandler app2 = null;
    private final long ROUTECOUNT = 1000;
   
    public void testManyPing() {
    Thread t1 = new Thread() {
        public void run() {
           for (long cc = 0; cc<ROUTECOUNT; cc++) {
            node1.routeAsync(10, new PingMsg(cc).flatten());
            Thread.yield();
           }
        }
       };
       
    Thread t2 = new Thread() {
        public void run() {
           for (long cc = 0; cc<ROUTECOUNT; cc++) {
            node2.routeAsync(0, new PingMsg(cc).flatten());
            Thread.yield();
           }
        }
       };
       
    t1.start();
    t2.start();
    try {
       t1.join();
       t2.join();
    } catch (Exception ex) {
       ex.printStackTrace();
    }

    // *** This is were I get the fishy behaviour.
       
    System.out.println();
    long c1 = app1.getCount();
    long c2 = app2.getCount();
    assertEquals(c1, c2);
    assertEquals(c1, ROUTECOUNT);
    }
   
    public void setUp() {
    try {
       cm1 = ConnectionManager.newInstance( (int) START_PORT); // Static
factory only used for testing, should use getInstance (singleton)
       cm2 = ConnectionManager.newInstance( (int) START_PORT+1); // Static
factory only used for testing, should use getInstance (singleton)
           
       app1 = new AppHandler("node1");
       app2 = new AppHandler("node2");
       node1 = new DHTImpl(cm1, app1);
       node2 = new DHTImpl(cm1, app2);
           
       node1.create();
           
       node2.join( node1 );
           
    }
    catch (Exception ex) {
       ex.printStackTrace();
    }       
    }
   
    public void tearDown() {
    sleep(500);
    node1.leave(); // causes the node to gracefully leave
    sleep(500);
    node2.leave(); // causes the node to gracefully leave
    sleep(500);
       
    cm1.end(); // Closes down all the sockets and threads
    cm2.end(); // Closes down all the sockets and threads
    }
   
    public void sleep(int msec) {
    try {
       Thread.sleep(msec);
    }
    catch (Exception ex)
       {
        ex.printStackTrace();
       }
    }
   
    public static class AppHandler implements DHTCallback {
    private String name = "";
    private Boolean bol = Boolean.FALSE;
    private long count = 0;
       
    public synchronized long getCount() { return count; }
    public synchronized void incCount() { count++; }
       
    public boolean getBool() {
       boolean tmp;
       synchronized (bol) {
        tmp = bol.booleanValue();   
       }
       return tmp;
    }
       
    public void setBool(boolean b) {
       synchronized (bol) {
        bol = Boolean.valueOf(b);
       }
    }
       
    public void dhtRouteCallbackAsync(long identifier, DKSMessage payload) {
       if (payload instanceof PingMsg) {
        setBool(true);
        incCount();
        PingMsg p = (PingMsg) payload;
        System.out.println(name+": got ping("+p.getCount()+")"+"
total("+getCount()+")");
       } else {
        System.err.println("Error parsting : "+payload);
       }
    }
       
    }
   
}