Class TaskExecutor


  • public final class TaskExecutor
    extends Object
    Executor wrapper responsible for the execution of concurrent tasks. Used to parallelize search across segments as well as query rewrite in some cases. Exposes a single invokeAll(Collection) method that takes a collection of Callables and executes them concurrently. Once all but one task have been submitted to the executor, it tries to run as many tasks as possible on the calling thread, then waits for all tasks that have been executed in parallel on the executor to be completed and then returns a list with the obtained results.
    WARNING: This API is experimental and might change in incompatible ways in the next release.
    • Constructor Detail

      • TaskExecutor

        public TaskExecutor​(Executor executor)
        Creates a TaskExecutor instance
        Parameters:
        executor - the executor to be used for running tasks concurrently
    • Method Detail

      • invokeAll

        public <T> List<T> invokeAll​(Collection<Callable<T>> callables)
                              throws IOException
        Execute all the callables provided as an argument, wait for them to complete and return the obtained results. If an exception is thrown by more than one callable, the subsequent ones will be added as suppressed exceptions to the first one that was caught.
        Type Parameters:
        T - the return type of the task execution
        Parameters:
        callables - the callables to execute
        Returns:
        a list containing the results from the tasks execution
        Throws:
        IOException