Package org.apache.druid.client

Interface ServerView.ServerCallback

Enclosing interface:
ServerView
public static interface ServerView.ServerCallback

  • Method Details

    • serverAdded

      ServerView.CallbackAction serverAdded(DruidServer server)
      Called when a server is added. The return value indicates if this callback has completed its work. Note that even if this callback indicates that it should be unregistered, it is not possible to guarantee that this callback will not get called again. There is a race condition between when this callback runs and other events that can cause the callback to be queued for running. Thus, callbacks shouldn't assume that they will not get called again after they are done. The contract is that the callback will eventually be unregistered, enforcing a happens-before relationship is not part of the contract.
      Parameters:
      server - The server that was added.
      Returns:
      UNREGISTER if the callback has completed its work and should be unregistered. CONTINUE if the callback should remain registered.

    • serverRemoved

      ServerView.CallbackAction serverRemoved(DruidServer server)
      Called when a server is removed. The return value indicates if this callback has completed its work. Note that even if this callback indicates that it should be unregistered, it is not possible to guarantee that this callback will not get called again. There is a race condition between when this callback runs and other events that can cause the callback to be queued for running. Thus, callbacks shouldn't assume that they will not get called again after they are done. The contract is that the callback will eventually be unregistered, enforcing a happens-before relationship is not part of the contract.
      Parameters:
      server - The server that was removed.
      Returns:
      UNREGISTER if the callback has completed its work and should be unregistered. CONTINUE if the callback should remain registered.