RFR[8234148]: DatagramSocket.setOption/getOption/supportedOption should support multicast options

[Patrick Concannon]

Hi,


Could some please review my fix for issue JDK-8234148 
'DatagramSocket.setOption/getOption/supportedOption should support 
multicast options'?

DatagramSocket can be used to send multicast datagrams but it isn't 
possible to set multicast options on it. This fix adds multicast socket 
options to DatagramSocket.

bug: https://bugs.openjdk.java.net/browse/JDK-8234148

webrev: http://cr.openjdk.java.net/~pconcannon/8234148/webrevs/webrev.00/

Kind regards,

Patrick