Is MulticastSocket.send() reentrant?

Question

I have 2 threads that want to invoke:

multicastSocket.send(dP1) and

multicastSocket.send(dP2)

respectively, where dP1 and dP2 are different DatagramPacket objects, and multicastSocket is the shared instance of MulticastSocket.

I don't understand if concurrency problems may happen on multicastSocket, if the threads call send() in the same moment.

possible duplicate http://stackoverflow.com/questions/3108644/is-java-multicastsocket-threadsafe — Alex, May 30 '15 at 16:00
Alex, looking at the bottom of the question you linked, it is said that send is not a synchronized method. So concurrency problems may eventually happen? However I guess this is not a duplicate question. — diningphil, May 30 '15 at 16:06

score 2 · Accepted Answer · answered May 30 '15 at 19:04

DatagramSocket reads and writes are independent of each other.
DatagramSocket writes are atomic so they are thread-safe.
DatagramSocket reads are synchronized by Java and they are also atomic at the OS level so again they are thread-safe.
MulticastSocket inherits these methods from DatagramSocket so the same applies to it.

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