Service Configuration and Coordination - Real-Time Analytics - page 78

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Leader Elections
Curator provides two recipes for implementing Leader Elections: a
LeaderSelector class and a LeaderLatch class. The LeaderSelector
class uses a callback mechanism to implement its functionality, whereas the
LeaderLatch class uses a process similar to the earlier Leader Election
example using the native Java API.
To use the LeaderSelector , the server trying to obtain leadership of
the process must implement the LeaderSelectorListener interface.
This interface specifies the takeLeadership method, which serves as the
main method for the server. Returning from this method relinquishes the
leadershipposition.Forexample,adummyunreliableservermightlooklike
this:
public class UnreliableLeader implements
LeaderSelectorListener {
String name = "";
boolean leader = false ;
String connect;