org.apache.hadoop.fs.statistics.impl.StorageStatisticsFromIOStatistics Maven / Gradle / Ivy
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* 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.hadoop.fs.statistics.impl;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;
import org.apache.hadoop.fs.StorageStatistics;
import org.apache.hadoop.fs.statistics.IOStatistics;
/**
* Returns all the counters of an IOStatistics instance as StorageStatistics.
* This is dynamic.
* The {@link #reset()} is downgraded to a no-op.
*/
public class StorageStatisticsFromIOStatistics
extends StorageStatistics
implements Iterable {
private final IOStatistics ioStatistics;
private final String scheme;
/**
* Instantiate.
* @param name storage statistics name.
* @param scheme FS scheme; may be null.
* @param ioStatistics IOStatistics source.
*/
public StorageStatisticsFromIOStatistics(
final String name,
final String scheme,
final IOStatistics ioStatistics) {
super(name);
this.scheme = scheme;
this.ioStatistics = ioStatistics;
}
@Override
public Iterator iterator() {
return getLongStatistics();
}
/**
* Take a snapshot of the current counter values
* and return an iterator over them.
* @return all the counter statistics.
*/
@Override
public Iterator getLongStatistics() {
final Set> counters = counters()
.entrySet();
final Set statisticSet = counters.stream().map(
this::toLongStatistic)
.collect(Collectors.toSet());
// add the gauges
gauges().entrySet().forEach(entry ->
statisticSet.add(toLongStatistic(entry)));
return statisticSet.iterator();
}
/**
* Convert a counter/gauge entry to a long statistics.
* @param e entry
* @return statistic
*/
private LongStatistic toLongStatistic(final Map.Entry e) {
return new LongStatistic(e.getKey(), e.getValue());
}
private Map counters() {
return ioStatistics.counters();
}
private Map gauges() {
return ioStatistics.gauges();
}
@Override
public Long getLong(final String key) {
Long l = counters().get(key);
if (l == null) {
l = gauges().get(key);
}
return l;
}
@Override
public boolean isTracked(final String key) {
return counters().containsKey(key)
|| gauges().containsKey(key);
}
@Override
public void reset() {
/* no-op */
}
@Override
public String getScheme() {
return scheme;
}
}