org.apache.tinkerpop.gremlin.driver

## Class ResultSet

- java.lang.Object
- - org.apache.tinkerpop.gremlin.driver.ResultSet

- All Implemented Interfaces:
    Iterable<Result>

      public final class ResultSet
      extends Object
      implements Iterable<Result>

  A `ResultSet` is returned from the submission of a Gremlin script to the server and represents the results provided by the server. The results from the server are streamed into the `ResultSet` and therefore may not be available immediately. As such, `ResultSet` provides access to a a number of functions that help to work with the asynchronous nature of the data streaming back. Data from results is stored in an `Result` which can be used to retrieve the item once it is on the client side.

  Note that a `ResultSet` is a forward-only stream only so depending on how the methods are called and interacted with, it is possible to return partial bits of the total response (e.g. calling `one()` followed by `all()` will make it so that the `List` of results returned from `all()` have one `Result` missing from the total set as it was already retrieved by `one()`.

  This class is not thread-safe.
  Author:
    Stephen Mallette (http://stephen.genoprime.com)

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `ResultSet(org.apache.tinkerpop.gremlin.driver.ResultQueue resultQueue, ExecutorService executor, CompletableFuture<Void> readCompleted, RequestMessage originalRequestMessage, Host host)`

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `CompletableFuture<List<Result>>` | `all()` The returned `CompletableFuture` completes when all reads are complete for this request and the entire result has been accounted for on the client.
    `boolean` | `allItemsAvailable()` Determines if all items have been returned to the client.
    `CompletableFuture<Void>` | `allItemsAvailableAsync()` Returns a future that will complete when all items have been returned from the server.
    `int` | `getAvailableItemCount()` Gets the number of items available on the client.
    `Host` | `getHost()`
    `RequestMessage` | `getOriginalRequestMessage()`
    `Iterator<Result>` | `iterator()` Returns a blocking iterator of the items streaming from the server to the client.
    `Result` | `one()` Get the next `Result` from the stream, blocking until one is available.
    `CompletableFuture<List<Result>>` | `some(int items)` The returned `CompletableFuture` completes when the number of items specified are available.
    `CompletableFuture<Map<String,Object>>` | `statusAttributes()` Returns a future that will complete when `allItemsAvailable()` is `true` and will contain the attributes from the response.
    `Stream<Result>` | `stream()` Stream items with a blocking iterator.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

    - ### Methods inherited from interface java.lang.Iterable

      `forEach, spliterator`

- - ### Constructor Detail

    - #### ResultSet

          public ResultSet(org.apache.tinkerpop.gremlin.driver.ResultQueue resultQueue,
                           ExecutorService executor,
                           CompletableFuture<Void> readCompleted,
                           RequestMessage originalRequestMessage,
                           Host host)

  - ### Method Detail

    - #### getOriginalRequestMessage

          public RequestMessage getOriginalRequestMessage()

    - #### getHost

          public Host getHost()

    - #### statusAttributes

          public CompletableFuture<Map<String,Object>> statusAttributes()

      Returns a future that will complete when `allItemsAvailable()` is `true` and will contain the attributes from the response.

    - #### allItemsAvailable

          public boolean allItemsAvailable()

      Determines if all items have been returned to the client.

    - #### allItemsAvailableAsync

          public CompletableFuture<Void> allItemsAvailableAsync()

      Returns a future that will complete when all items have been returned from the server.

    - #### getAvailableItemCount

          public int getAvailableItemCount()

      Gets the number of items available on the client.

    - #### one

          public Result one()

      Get the next `Result` from the stream, blocking until one is available.

    - #### some

          public CompletableFuture<List<Result>> some(int items)

      The returned `CompletableFuture` completes when the number of items specified are available. The number returned will be equal to or less than that number. They will only be less if the stream is completed and there are less than that number specified available.

    - #### all

          public CompletableFuture<List<Result>> all()

      The returned `CompletableFuture` completes when all reads are complete for this request and the entire result has been accounted for on the client. While this method is named "all" it really refers to retrieving all remaining items in the set. For large result sets it is preferred to use `Iterator` or `Stream` options, as the results will be held in memory at once.

    - #### stream

          public Stream<Result> stream()

      Stream items with a blocking iterator.

    - #### iterator

          public Iterator<Result> iterator()

      Returns a blocking iterator of the items streaming from the server to the client. This `Iterator` will consume results as they arrive and leaving the `ResultSet` empty when complete.

      The returned `Iterator` does not support the `Iterator.remove()` method.
      Specified by:
        `iterator` in interface `Iterable<Result>`

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