net.openhft.chronicle.queue.impl.RollingChronicleQueue Maven / Gradle / Ivy
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/*
* Copyright 2016-2020 chronicle.software
*
* https://chronicle.software
*
* 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 net.openhft.chronicle.queue.impl;
import net.openhft.chronicle.queue.ChronicleQueue;
import net.openhft.chronicle.queue.RollCycle;
import net.openhft.chronicle.queue.TailerDirection;
import net.openhft.chronicle.queue.impl.single.SingleChronicleQueueStore;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import java.text.ParseException;
public interface RollingChronicleQueue extends ChronicleQueue {
long epoch();
/**
* @param cycle the cycle
* @param epoch an epoch offset as the number of milliseconds since January
* 1, 1970, 00:00:00 GMT
* @param createIfAbsent create missing stores if true, or return null if missing
* @return the {@code WireStore} associated with this {@code cycle}, or null if !createIfAbsent
* is false and absent
*/
@Nullable
SingleChronicleQueueStore storeForCycle(int cycle, final long epoch, boolean createIfAbsent, SingleChronicleQueueStore oldStore);
/**
* @return the first cycle number found, or Integer.MAX_VALUE is none found.
*/
int firstCycle();
/**
* @return the lastCycle available or Integer.MIN_VALUE if none is found.
*/
int lastCycle();
/**
* Counts the number of messages in this queue instance.
*
* @return the number of document excerpts
*/
long entryCount();
/**
* the next available cycle, no cycle will be created by this method, this method is typically
* used by a tailer to jump to the next cycle when the cycles are not adjacent.
*
* @param currentCycle the current cycle
* @param direction the direction
* @return the next available cycle from the current cycle, or -1 if there is no next cycle
*/
int nextCycle(int currentCycle, @NotNull TailerDirection direction) throws ParseException;
/**
* The number of excerpts between the indexes, {@code fromIndex} inclusive, {@code toIndex}
* exclusive.
*
* When {@code fromIndex} and {@code toIndex} are in different cycles which are not adjacent, this
* operation can be expensive, as the index count for each intermediate cycle has to be found
* and calculated. As such, and in this situation, it's not recommended to call this method
* regularly in latency sensitive systems.
*
* @param fromIndex from index, the index provided must exist. To improve performance no checking
* is carried out to validate if an excerpt exists at this index. ( inclusive )
* @param toIndex to index, the index provided must exist. To improve performance no checking is
* carried out to validate if an excerpt exists at this index. ( exclusive )
* @return the number of excerpts between the indexes, {@code index1} inclusive, {@code index2}
* exclusive.
* @throws java.lang.IllegalStateException if the cycle of {@code fromIndex} or {@code toIndex} can
* not be ascertained
*/
long countExcerpts(long fromIndex, long toIndex);
/**
* @return the current cycle
*/
int cycle();
/**
* @return the max size of each index and also the number number of index arrays. indexCount^2 is the maximum number of index queue entries.
*/
int indexCount();
/**
* @return the spacing between indexed entries. If 1 then every entry is indexed.
*/
int indexSpacing();
@NotNull
RollCycle rollCycle();
/**
* @return the checkpointInterval used by delta wire
*/
int deltaCheckpointInterval();
}