In message <aanlktimsn8peujvw3jgmhyakdahuslwptsfcmhdt1...@mail.gmail.com>,
Charles Lee writes:
>
> On Tue, Jun 8, 2010 at 3:18 PM, Mark Hindess <mark.hind...@googlemail.com>
> wrote:
> >
> > I was looking at failing tests on FreeBSD and I spotted the following
> > test in DatagramPacketTest.java:
> >
> > public void test_getPort() throws IOException {
> > DatagramPacket dp = new DatagramPacket("Hello".getBytes(), 5,
> > InetAddress.getLocalHost(), 1000);
> > assertEquals("Incorrect port returned", 1000, dp.getPort());
> >
> > final InetAddress localhost = InetAddress.getLocalHost();
> > DatagramSocket socket = new DatagramSocket(0, localhost);
> > final int port = socket.getLocalPort();
> >
> > final Object lock = new Object();
> >
> > Thread thread = new Thread(new Runnable() {
> > public void run() {
> > DatagramSocket socket = null;
> > try {
> > socket = new DatagramSocket(0, localhost);
> > synchronized (lock) {
> > started = true;
> > lock.notifyAll();
> > }
> > socket.setSoTimeout(3000);
> > DatagramPacket packet = new DatagramPacket(new byte[256],
> > 256);
> > socket.receive(packet);
> > socket.send(packet);
> > socket.close();
> > } catch (IOException e) {
> > System.out.println("thread exception: " + e);
> > if (socket != null)
> > socket.close();
> > }
> > }
> > });
> > thread.start();
> >
> > socket.setSoTimeout(3000);
> > DatagramPacket packet = new DatagramPacket(new byte[] { 1, 2, 3, 4,
> > 5,
> > 6 }, 6, localhost, port);
> > synchronized (lock) {
> > while (!started) {
> > try {
> > lock.wait();
> > } catch (InterruptedException e) {
> > }
> > }
> > }
> > socket.send(packet);
> > socket.receive(packet);
> > socket.close();
> > assertTrue("datagram received wrong port: " + packet.getPort(),
> > packet
> > .getPort() == port);
> > }
> >
> > Notice that main threads socket is being used to send to itself - not to
> > the other socket which is left waiting until timeout for a packet from
> > itself that it hasn't sent yet! I think this can be more simply written
> > as:
> >
> > public void test_getPort() throws IOException {
> > DatagramPacket dp = new DatagramPacket("Hello".getBytes(), 5,
> > InetAddress.getLocalHost(), 1000);
> > assertEquals("Incorrect port returned", 1000, dp.getPort());
> >
> > final InetAddress localhost = InetAddress.getLocalHost();
> > DatagramSocket socket = new DatagramSocket(0, localhost);
> > final int port = socket.getLocalPort();
> >
> > socket.setSoTimeout(3000);
> > DatagramPacket packet = new DatagramPacket(new byte[] { 1, 2, 3, 4,
> > 5,
> > 6 }, 6, localhost, port);
> > socket.send(packet);
> > socket.receive(packet);
> > socket.close();
> > assertTrue("datagram received wrong port: " + packet.getPort(),
> > packet
> > .getPort() == port);
> > }
> >
> > Does that make sense or am I missing something?
>
> It seems the original one transfer packet in two directions, but the
> new version only transfer the packet in one way.
The original does a send then receive in the testing thread. But the
other thread does only a receive which times out with an exception but
the exception is ignored so it is not testing anything.
I assume the intention was for the two threads to send each other a
packet but the original test does not do that.
The new version only has the original testing thread. I don't think
anything is lost. (Except perhaps that the test would hang if the
receive in the second thread did not timeout but there are more
obvious/sane ways to test this.)
> > Sadly they both fail on FreeBSD.
I know why the fail on FreeBSD now.
Regards,
Mark.
