Package org.apache.ignite.spi.discovery

## Interface DiscoverySpiCustomMessage

- All Superinterfaces:
    `Serializable`

      public interface DiscoverySpiCustomMessage
      extends Serializable

  Message to send across ring.
  See Also:
    `GridDiscoveryManager.sendCustomEvent(DiscoveryCustomMessage)`

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `@Nullable DiscoverySpiCustomMessage` | `ackMessage()` | Called when custom message has been handled by all nodes.
    `boolean` | `isMutable()` |
    `boolean` | `stopProcess()` | Called on discovery coordinator node after listener is notified.

- - ### Method Detail

    - #### ackMessage

          @Nullable
          @Nullable DiscoverySpiCustomMessage ackMessage()

      Called when custom message has been handled by all nodes.
      Returns:
        Ack message or `null` if ack is not required.

    - #### isMutable

          boolean isMutable()

      Returns:
        `True` if message can be modified during listener notification. Changes will be send to next nodes.

    - #### stopProcess

          boolean stopProcess()

      Called on discovery coordinator node after listener is notified. If returns `true` then message is not passed to others nodes, if after this method `ackMessage()` returns non-null ack message, it is sent to all nodes. Note: this method is used then and only then the zookeeper discovery is configured.
      Returns:
        `True` if message should not be sent to all nodes.