io.prestosql.plugin.hive.util

Class ThrottledAsyncQueue<T>

java.lang.Object

io.prestosql.plugin.hive.util.AsyncQueue<T>

io.prestosql.plugin.hive.util.ThrottledAsyncQueue<T>

Type Parameters:

T - The type of elements accepted by the queue.

@ThreadSafe
public class ThrottledAsyncQueue<T>
extends AsyncQueue<T>

An asynchronous queue that limits the rate at which batches will be made available as well as the number of elements they will contain.

Nested Class Summary

Nested classes/interfaces inherited from class io.prestosql.plugin.hive.util.AsyncQueue

AsyncQueue.BorrowResult<T,R>

Constructor Summary

Constructors

Constructor and Description
ThrottledAsyncQueue(int maxBatchSizePerSec, int targetQueueSize, Executor executor)

Method Summary

Modifier and Type	Method and Description
<O> com.google.common.util.concurrent.ListenableFuture<O>	borrowBatchAsync(int maxSize, Function<List<T>,AsyncQueue.BorrowResult<T,O>> function) Invoke function with up to maxSize elements removed from the head of the queue, and insert elements in the return value to the tail of the queue.

Methods inherited from class io.prestosql.plugin.hive.util.AsyncQueue

finish, getBatchAsync, getNotEmptySignal, isFinished, offer, size

Methods inherited from class java.lang.Object

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

Constructor Detail

ThrottledAsyncQueue

public ThrottledAsyncQueue(int maxBatchSizePerSec,
                           int targetQueueSize,
                           Executor executor)

Method Detail

borrowBatchAsync

public <O> com.google.common.util.concurrent.ListenableFuture<O> borrowBatchAsync(int maxSize,
                                                                                  Function<List<T>,AsyncQueue.BorrowResult<T,O>> function)

Description copied from class: AsyncQueue

Invoke function with up to maxSize elements removed from the head of the queue, and insert elements in the return value to the tail of the queue.

If no element is currently available, invocation of function will be deferred until some element is available, or no more elements will be. Spurious invocation of function is possible.

Insertion through return value of function will be effective even if AsyncQueue.finish() has been invoked. When borrow (of a non-empty list) is ongoing, AsyncQueue.isFinished() will return false. If an empty list is supplied to function, it must not return a result indicating intention to insert elements into the queue.

Overrides:

borrowBatchAsync in class AsyncQueue<T>