Interface ResponseCollector<T>

All Known Implementing Classes:
AutoStateTransferResponseCollector, FilterMapResponseCollector, MapResponseCollector, PassthroughMapResponseCollector, PassthroughSingleResponseCollector, SingleResponseCollector, SingletonMapResponseCollector, ValidResponseCollector, ValidSingleResponseCollector, VoidResponseCollector
@Experimental public interface ResponseCollector<T>
A representation of a request's responses.

Thread-safety: The request will invoke addResponse(Address, Response) and finish() in a mutually exclusive way. If addResponse(Address, Response) is invoked more than once it may be on different threads, but never concurrently and only with a happens-before operation ensuring proper visibility, allowing implementations to use non concurrent structures.

Since:
9.1
Author:
Dan Berindei

  • Method Details

    • addResponse

      T addResponse(Address sender, Response response)
      Called when a response is received, or when a target node becomes unavailable.

      When a target node leaves the cluster, this method is called with a CacheNotFoundResponse.

      Should return a non-null result if the request should complete with that value, or null if it should wait for more responses. If the method throws an exception, the request will be completed with that exception. If the last response is received and addResponse() still returns null, finish() will also be called to obtain a result.

      Thread safety: addResponse() will *not* be called concurrently from multiple threads, and the request will not be completed while addResponse() is running.

    • finish

      T finish()
      Called after addResponse(Address, Response) returns null for the last response.

      If finish() finishes normally, the request will complete with its return value (even if null). If finish() throws an exception, the request will complete exceptionally with that exception, wrapped in a CompletionException (unless the exception is already a CompletionException).