com.lmax.disruptor.SequenceBarrier Maven / Gradle / Ivy
/*
* Copyright 2011 LMAX Ltd.
*
* 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 com.lmax.disruptor;
/**
* Coordination barrier for tracking the cursor for publishers and sequence of
* dependent {@link EventProcessor}s for processing a data structure
*/
public interface SequenceBarrier
{
/**
* Wait for the given sequence to be available for consumption.
*
* @param sequence to wait for
* @return the sequence up to which is available
* @throws AlertException if a status change has occurred for the Disruptor
* @throws InterruptedException if the thread needs awaking on a condition variable.
* @throws TimeoutException if a timeout occurs while waiting for the supplied sequence.
*/
long waitFor(long sequence) throws AlertException, InterruptedException, TimeoutException;
/**
* Get the current cursor value that can be read.
*
* @return value of the cursor for entries that have been published.
*/
long getCursor();
/**
* The current alert status for the barrier.
*
* @return true if in alert otherwise false.
*/
boolean isAlerted();
/**
* Alert the {@link EventProcessor}s of a status change and stay in this status until cleared.
*/
void alert();
/**
* Clear the current alert status.
*/
void clearAlert();
/**
* Check if an alert has been raised and throw an {@link AlertException} if it has.
*
* @throws AlertException if alert has been raised.
*/
void checkAlert() throws AlertException;
}