kafka ControllerPurgatory 源码

kafka ControllerPurgatory 代码

文件路径：/metadata/src/main/java/org/apache/kafka/controller/ControllerPurgatory.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.kafka.controller;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map.Entry;
import java.util.OptionalLong;
import java.util.TreeMap;

/**
 * The purgatory which holds events that have been started, but not yet completed.
 * We wait for the high water mark of the metadata log to advance before completing
 * them.
 */
class ControllerPurgatory {
    /**
     * A map from log offsets to events.  Each event will be completed once the log
     * advances past its offset.
     */
    private final TreeMap<Long, List<DeferredEvent>> pending = new TreeMap<>();

    /**
     * Complete some purgatory entries.
     *
     * @param offset        The offset which the high water mark has advanced to.
     */
    void completeUpTo(long offset) {
        Iterator<Entry<Long, List<DeferredEvent>>> iter = pending.entrySet().iterator();
        while (iter.hasNext()) {
            Entry<Long, List<DeferredEvent>> entry = iter.next();
            if (entry.getKey() > offset) {
                break;
            }
            for (DeferredEvent event : entry.getValue()) {
                event.complete(null);
            }
            iter.remove();
        }
    }

    /**
     * Fail all the pending purgatory entries.
     *
     * @param exception     The exception to fail the entries with.
     */
    void failAll(Exception exception) {
        Iterator<Entry<Long, List<DeferredEvent>>> iter = pending.entrySet().iterator();
        while (iter.hasNext()) {
            Entry<Long, List<DeferredEvent>> entry = iter.next();
            for (DeferredEvent event : entry.getValue()) {
                event.complete(exception);
            }
            iter.remove();
        }
    }

    /**
     * Add a new purgatory event.
     *
     * @param offset        The offset to add the new event at.
     * @param event         The new event.
     */
    void add(long offset, DeferredEvent event) {
        if (!pending.isEmpty()) {
            long lastKey = pending.lastKey();
            if (offset < lastKey) {
                throw new RuntimeException("There is already a purgatory event with " +
                    "offset " + lastKey + ".  We should not add one with an offset of " +
                    offset + " which " + "is lower than that.");
            }
        }
        List<DeferredEvent> events = pending.get(offset);
        if (events == null) {
            events = new ArrayList<>();
            pending.put(offset, events);
        }
        events.add(event);
    }

    /**
     * Get the offset of the highest pending event, or empty if there are no pending
     * events.
     */
    OptionalLong highestPendingOffset() {
        if (pending.isEmpty()) {
            return OptionalLong.empty();
        } else {
            return OptionalLong.of(pending.lastKey());
        }
    }
}

相关信息

kafka 源码目录

相关文章

kafka AclControlManager 源码

kafka BrokerControlState 源码

kafka BrokerControlStates 源码

kafka BrokerHeartbeatManager 源码

kafka BrokersToIsrs 源码

kafka ClientQuotaControlManager 源码

kafka ClusterControlManager 源码

kafka ConfigurationControlManager 源码

kafka ConfigurationValidator 源码

kafka Controller 源码