Class GrpclbLoadBalancer

java.lang.Object
io.grpc.LoadBalancer
io.grpc.grpclb.GrpclbLoadBalancer

class GrpclbLoadBalancer extends LoadBalancer
A LoadBalancer that uses the GRPCLB protocol.

Optionally, when requested by the naming system, will delegate the work to a local pick-first or round-robin balancer.

  • Field Details

  • Constructor Details

  • Method Details

    • acceptResolvedAddresses

      public Status acceptResolvedAddresses(LoadBalancer.ResolvedAddresses resolvedAddresses)
      Description copied from class: LoadBalancer
      Accepts newly resolved addresses from the name resolution system. The EquivalentAddressGroup addresses should be considered equivalent but may be flattened into a single list if needed.

      Implementations can choose to reject the given addresses by returning false.

      Implementations should not modify the given addresses.

      Overrides:
      acceptResolvedAddresses in class LoadBalancer
      Parameters:
      resolvedAddresses - the resolved server addresses, attributes, and config.
      Returns:
      true if the resolved addresses were accepted. false if rejected.
    • requestConnection

      public void requestConnection()
      Description copied from class: LoadBalancer
      The channel asks the LoadBalancer to establish connections now (if applicable) so that the upcoming RPC may then just pick a ready connection without waiting for connections. This is triggered by ManagedChannel.getState(true).

      If LoadBalancer doesn't override it, this is no-op. If it infeasible to create connections given the current state, e.g. no Subchannel has been created yet, LoadBalancer can ignore this request.

      Overrides:
      requestConnection in class LoadBalancer
    • resetStates

      private void resetStates()
    • recreateStates

      private void recreateStates()
    • shutdown

      public void shutdown()
      Description copied from class: LoadBalancer
      The channel asks the load-balancer to shutdown. No more methods on this class will be called after this method. The implementation should shutdown all Subchannels and OOB channels, and do any other cleanup as necessary.
      Specified by:
      shutdown in class LoadBalancer
    • handleNameResolutionError

      public void handleNameResolutionError(Status error)
      Description copied from class: LoadBalancer
      Handles an error from the name resolution system.
      Specified by:
      handleNameResolutionError in class LoadBalancer
      Parameters:
      error - a non-OK status
    • canHandleEmptyAddressListFromNameResolution

      public boolean canHandleEmptyAddressListFromNameResolution()
      Description copied from class: LoadBalancer
      Whether this LoadBalancer can handle empty address group list to be passed to LoadBalancer.handleResolvedAddresses(ResolvedAddresses). The default implementation returns false, meaning that if the NameResolver returns an empty list, the Channel will turn that into an error and call LoadBalancer.handleNameResolutionError(io.grpc.Status). LoadBalancers that want to accept empty lists should override this method and return true.

      This method should always return a constant value. It's not specified when this will be called.

      Overrides:
      canHandleEmptyAddressListFromNameResolution in class LoadBalancer
    • getGrpclbState

      @Nullable GrpclbState getGrpclbState()