org.apache.hadoop.fs.statistics.DurationTracker 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.hadoop.fs.statistics;
import java.time.Duration;
/**
* Interface to be implemented by objects which can track duration.
* It extends AutoCloseable to fit into a try-with-resources statement,
* but then strips out the {@code throws Exception} aspect of the signature
* so it doesn't force code to add extra handling for any failures.
*
* If a duration is declared as "failed()" then the failure counters
* will be updated.
*/
public interface DurationTracker extends AutoCloseable {
/**
* The operation failed. Failure statistics will be updated.
*/
void failed();
/**
* Finish tracking: update the statistics with the timings.
*/
void close();
/**
* Get the duration of an operation as a java Duration
* instance. If the duration tracker hasn't completed,
* or its duration tracking doesn't actually measure duration,
* returns Duration.ZERO.
* @return a duration, value of ZERO until close().
*/
default Duration asDuration() {
return Duration.ZERO;
}
}