    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 *      https://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 timestampedObserver = new TimestampedObserver();
    034 * try (ObservableInputStream inputStream = new ObservableInputStream(...),
    035 *     timestampedObserver)) {
    036 *     ...
    037 * }
    038 * System.out.printf("IO duration: %s%n", timestampedObserver.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    /**
    049     * Constructs a new instance.
    050     */
    051    public TimestampedObserver() {
    052        // empty
    053    }
    054
    055    @Override
    056    public void closed() throws IOException {
    057        closeInstant = Instant.now();
    058    }
    059
    060    /**
    061     * Gets the instant for when this instance was closed.
    062     *
    063     * @return the instant for when closed was called.
    064     */
    065    public Instant getCloseInstant() {
    066        return closeInstant;
    067    }
    068
    069    /**
    070     * Gets the instant for when this instance was created.
    071     *
    072     * @return the instant for when this instance was created.
    073     */
    074    public Instant getOpenInstant() {
    075        return openInstant;
    076    }
    077
    078    /**
    079     * Gets the Duration between creation and close.
    080     *
    081     * @return the Duration between creation and close.
    082     */
    083    public Duration getOpenToCloseDuration() {
    084        return Duration.between(openInstant, closeInstant);
    085    }
    086
    087    /**
    088     * Gets the Duration between creation and now.
    089     *
    090     * @return the Duration between creation and now.
    091     */
    092    public Duration getOpenToNowDuration() {
    093        return Duration.between(openInstant, Instant.now());
    094    }
    095
    096    /**
    097     * Tests whether {@link #closed()} has been called.
    098     *
    099     * @return whether {@link #closed()} has been called.
    100     * @since 2.12.0
    101     */
    102    public boolean isClosed() {
    103        return closeInstant != null;
    104    }
    105
    106    @Override
    107    public String toString() {
    108        return "TimestampedObserver [openInstant=" + openInstant + ", closeInstant=" + closeInstant + "]";
    109    }
    110
    111}