Preventing IgniteHeartbeat race condition on the start of IgniteService (Issue #72)

[michaeldinzinger]

Signed-off-by: Michael Dinzinger michael.dinzinger@uni-passau.de

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[jnioche]

A simpler approach would be to force FrontierServices to have a constructor containing (String host, String port) so that these values would be set before the Hearbeat thread starts working.
Alternatively, we could introduce a new method start() for FrontierServices and call that after service.setHostAndPort(host, port); in the server class. We'd separate the instantiation from the actual starting of the various subthreads.
What do you think @michaeldinzinger?

[michaeldinzinger]

I like the first idea to add host and port to the constructor. It should fix the problem and is easy to implement and understand
(Don't be irritated that I uploaded two commits. First, I looked at the idea to add the start() method, but reverted the changes and implemented the idea to modify the constructor; it seems to be better coding style)
However, it has to be considered that the constructor has to be changed in all implementations, also in the opensearch implementation as soon as it would use this newer version of the urlfrontier code, in the future

[jnioche]

Perfect, thanks @michaeldinzinger