Java control IP TTL?

Question

In Java, is there a way to control the TTL of the IP header for packets sent on a socket?

Answer 1

Apparently only on Multicast sockets, which have:

MulticastSocket.setTimeToLive(int ttl);

Answer 2

Setting the TTL using

MulticastSocket.setTimeToLive(int ttl);

is only going to work if you have enabled the IPV4Stack as outlined by this other question

http://stackoverflow.com/questions/139909/java-multicast-time-to-live-is-always-0

-Djava.net.preferIPv4Stack=true