001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.io.input;
019
020import java.io.IOException;
021import java.time.Duration;
022import java.time.Instant;
023
024import org.apache.commons.io.input.ObservableInputStream.Observer;
025
026/**
027 * An observer with timestamps.
028 * <p>
029 * For example:
030 * </p>
031 *
032 * <pre>
033 * final TimestampedObserver timetampedObserver = new TimestampedObserver();
034 * try (final ObservableInputStream inputStream = new ObservableInputStream(...),
035 *     timetampedObserver)) {
036 *     ...
037 * }
038 * System.out.printf("IO duration: %s%n", timetampedObserver.getOpenToCloseDuration());
039 * </pre>
040 *
041 * @since 2.9.0
042 */
043public class TimestampedObserver extends Observer {
044
045    private volatile Instant closeInstant;
046    private final Instant openInstant = Instant.now();
047
048    @Override
049    public void closed() throws IOException {
050        closeInstant = Instant.now();
051    }
052
053    /**
054     * Gets the instant for when this instance was closed.
055     *
056     * @return the instant for when closed was called.
057     */
058    public Instant getCloseInstant() {
059        return closeInstant;
060    }
061
062    /**
063     * Gets the Duration between creation and close.
064     *
065     * @return the Duration between creation and close.
066     */
067    public Duration getOpenToCloseDuration() {
068        return Duration.between(openInstant, closeInstant);
069    }
070
071    /**
072     * Gets the Duration between creation and now.
073     *
074     * @return the Duration between creation and now.
075     */
076    public Duration getOpenToNowDuration() {
077        return Duration.between(openInstant, Instant.now());
078    }
079
080    /**
081     * Gets the instant for when this instance was created.
082     *
083     * @return the instant for when this instance was created.
084     */
085    public Instant getOpenInstant() {
086        return openInstant;
087    }
088
089    @Override
090    public String toString() {
091        return "TimestampedObserver [openInstant=" + openInstant + ", closeInstant=" + closeInstant + "]";
092    }
093
094}