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- /*
- * Copyright (C) 2016, Google Inc.
- * and other copyright owners as documented in the project's IP log.
- *
- * This program and the accompanying materials are made available
- * under the terms of the Eclipse Distribution License v1.0 which
- * accompanies this distribution, is reproduced below, and is
- * available at http://www.eclipse.org/org/documents/edl-v10.php
- *
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or
- * without modification, are permitted provided that the following
- * conditions are met:
- *
- * - Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * - Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following
- * disclaimer in the documentation and/or other materials provided
- * with the distribution.
- *
- * - Neither the name of the Eclipse Foundation, Inc. nor the
- * names of its contributors may be used to endorse or promote
- * products derived from this software without specific prior
- * written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
- * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
- * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
- package org.eclipse.jgit.util.time;
-
- import static java.util.concurrent.TimeUnit.MICROSECONDS;
- import static java.util.concurrent.TimeUnit.MILLISECONDS;
-
- import java.sql.Timestamp;
- import java.time.Duration;
- import java.time.Instant;
- import java.util.Date;
- import java.util.Iterator;
- import java.util.concurrent.TimeUnit;
- import java.util.concurrent.TimeoutException;
-
- /**
- * A timestamp generated by
- * {@link org.eclipse.jgit.util.time.MonotonicClock#propose()}.
- * <p>
- * ProposedTimestamp implements AutoCloseable so that implementations can
- * release resources associated with obtaining certainty about time elapsing.
- * For example the constructing MonotonicClock may start network IO with peers
- * when creating the ProposedTimestamp, and {@link #close()} can ensure those
- * network resources are released in a timely fashion.
- *
- * @since 4.6
- */
- public abstract class ProposedTimestamp implements AutoCloseable {
- /**
- * Wait for several timestamps.
- *
- * @param times
- * timestamps to wait on.
- * @param maxWait
- * how long to wait for the timestamps.
- * @throws java.lang.InterruptedException
- * current thread was interrupted before the waiting process
- * completed normally.
- * @throws java.util.concurrent.TimeoutException
- * the timeout was reached without the proposed timestamp become
- * certainly in the past.
- */
- public static void blockUntil(Iterable<ProposedTimestamp> times,
- Duration maxWait) throws TimeoutException, InterruptedException {
- Iterator<ProposedTimestamp> itr = times.iterator();
- if (!itr.hasNext()) {
- return;
- }
-
- long now = System.currentTimeMillis();
- long deadline = now + maxWait.toMillis();
- for (;;) {
- long w = deadline - now;
- if (w < 0) {
- throw new TimeoutException();
- }
- itr.next().blockUntil(Duration.ofMillis(w));
- if (itr.hasNext()) {
- now = System.currentTimeMillis();
- } else {
- break;
- }
- }
- }
-
- /**
- * Read the timestamp as {@code unit} since the epoch.
- * <p>
- * The timestamp value for a specific {@code ProposedTimestamp} object never
- * changes, and can be read before {@link #blockUntil(Duration)}.
- *
- * @param unit
- * what unit to return the timestamp in. The timestamp will be
- * rounded if the unit is bigger than the clock's granularity.
- * @return {@code unit} since the epoch.
- */
- public abstract long read(TimeUnit unit);
-
- /**
- * Wait for this proposed timestamp to be certainly in the recent past.
- * <p>
- * This method forces the caller to wait up to {@code timeout} for
- * {@code this} to pass sufficiently into the past such that the creating
- * {@link org.eclipse.jgit.util.time.MonotonicClock} instance will not
- * create an earlier timestamp.
- *
- * @param maxWait
- * how long the implementation may block the caller.
- * @throws java.lang.InterruptedException
- * current thread was interrupted before the waiting process
- * completed normally.
- * @throws java.util.concurrent.TimeoutException
- * the timeout was reached without the proposed timestamp
- * becoming certainly in the past.
- */
- public abstract void blockUntil(Duration maxWait)
- throws InterruptedException, TimeoutException;
-
- /**
- * Get milliseconds since epoch; {@code read(MILLISECONDS}).
- *
- * @return milliseconds since epoch; {@code read(MILLISECONDS}).
- */
- public long millis() {
- return read(MILLISECONDS);
- }
-
- /**
- * Get microseconds since epoch; {@code read(MICROSECONDS}).
- *
- * @return microseconds since epoch; {@code read(MICROSECONDS}).
- */
- public long micros() {
- return read(MICROSECONDS);
- }
-
- /**
- * Get time since epoch, with up to microsecond resolution.
- *
- * @return time since epoch, with up to microsecond resolution.
- */
- public Instant instant() {
- long usec = micros();
- long secs = usec / 1000000L;
- long nanos = (usec % 1000000L) * 1000L;
- return Instant.ofEpochSecond(secs, nanos);
- }
-
- /**
- * Get time since epoch, with up to microsecond resolution.
- *
- * @return time since epoch, with up to microsecond resolution.
- */
- public Timestamp timestamp() {
- return Timestamp.from(instant());
- }
-
- /**
- * Get time since epoch, with up to millisecond resolution.
- *
- * @return time since epoch, with up to millisecond resolution.
- */
- public Date date() {
- return new Date(millis());
- }
-
- /**
- * {@inheritDoc}
- * <p>
- * Release resources allocated by this timestamp.
- */
- @Override
- public void close() {
- // Do nothing by default.
- }
-
- /** {@inheritDoc} */
- @Override
- public String toString() {
- return instant().toString();
- }
- }
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