dev.responsive.kafka.api.async.internals.queues.ReadOnlyFinalizingQueue Maven / Gradle / Ivy
/*
* Copyright 2024 Responsive Computing, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package dev.responsive.kafka.api.async.internals.queues;
import dev.responsive.kafka.api.async.internals.AsyncProcessor;
import dev.responsive.kafka.api.async.internals.events.AsyncEvent;
import java.util.concurrent.TimeUnit;
/**
* A read-only version of the {@link FinalizingQueue} intended for the
* StreamThread to access (by way of the {@link AsyncProcessor}.
*
* This queue has both blocking and non-blocking versions of the read
* API so the StreamThread can finalize events as they finish processing
* during normal operation, but wait on the events being processed to
* be added so it can block instead of busy-waiting during the
* flush/commit procedure.
*
* See {@link FinalizingQueue} for full javadocs, and
* {@link WriteOnlyFinalizingQueue} for the write-only version of this queue
*/
public interface ReadOnlyFinalizingQueue {
/**
* Non-blocking read API that returns an event only when one is
* already available in the queue
*
* @return the next finalizable event, or null if there are none
*/
AsyncEvent nextFinalizableEvent();
/**
* Blocking read API that waits if necessary until the queue is
* non-empty then returns the next event in FIFO order.
*
* @return the next finalizable event, blocking if necessary until
* onr is available. Guaranteed to never return null
* @throws InterruptedException if interrupted while blocking
*/
AsyncEvent waitForNextFinalizableEvent(long timeout, TimeUnit unit) throws InterruptedException;
/**
* @return true if there are no currently-available events that are
* awaiting finalization in this queue
*/
boolean isEmpty();
}