org.apache.bookkeeper.util.OrderedGenericCallback Maven / Gradle / Ivy
/*
* 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.bookkeeper.util;
import java.util.Map;
import java.util.concurrent.RejectedExecutionException;
import org.apache.bookkeeper.common.util.MdcUtils;
import org.apache.bookkeeper.common.util.OrderedExecutor;
import org.apache.bookkeeper.proto.BookkeeperInternalCallbacks.GenericCallback;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.slf4j.MDC;
/**
* Generic callback implementation which will run the
* callback in the thread which matches the ordering key.
*/
public abstract class OrderedGenericCallback implements GenericCallback {
private static final Logger LOG = LoggerFactory.getLogger(OrderedGenericCallback.class);
private final OrderedExecutor executor;
private final long orderingKey;
private final Map mdcContextMap;
/**
* @param executor The executor on which to run the callback
* @param orderingKey Key used to decide which thread the callback
* should run on.
*/
public OrderedGenericCallback(OrderedExecutor executor, long orderingKey) {
this.executor = executor;
this.orderingKey = orderingKey;
this.mdcContextMap = executor.preserveMdc() ? MDC.getCopyOfContextMap() : null;
}
@Override
public final void operationComplete(final int rc, final T result) {
MdcUtils.restoreContext(mdcContextMap);
try {
// during closing, callbacks that are error out might try to submit to
// the scheduler again. if the submission will go to same thread, we
// don't need to submit to executor again. this is also an optimization for
// callback submission
if (Thread.currentThread().getId() == executor.getThreadID(orderingKey)) {
safeOperationComplete(rc, result);
} else {
try {
executor.executeOrdered(orderingKey, new Runnable() {
@Override
public void run() {
safeOperationComplete(rc, result);
}
@Override
public String toString() {
return String.format("Callback(key=%s, name=%s)",
orderingKey,
OrderedGenericCallback.this);
}
});
} catch (RejectedExecutionException re) {
LOG.warn("Failed to submit callback for {} : ", orderingKey, re);
}
}
} finally {
MDC.clear();
}
}
public abstract void safeOperationComplete(int rc, T result);
}