org.testifyproject.spotify.docker.client.DockerDateFormat Maven / Gradle / Ivy
/*-
* -\-\-
* docker-client
* --
* Copyright (C) 2016 Spotify AB
* --
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in org.testifyproject.testifyprojectpliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org.testifyproject/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.testifyproject.testifyproject.spotify.docker.client;
import org.testifyproject.testifyproject.fasterxml.jackson.databind.util.StdDateFormat;
import java.text.ParseException;
import java.util.Date;
/**
* Docker returns timestamps with nanosecond precision
* (e.g. 2014-10-17T21:22:56.949763914Z),
* but {@link Date} only supports milliseconds. Creating a Date from the nanosecond timestamp
* results in the date being set to several days after what date should be. This class converts the
* timestamp from nanoseconds to milliseconds by removing the last six digits of the timestamp, so
* we can generate a Date with the correct value (albeit with less precision).
*
* Note: a more org.testifyproject.testifyprojectplete solution would be to introduce a custom date type which can store the
* nanosecond value in an additional field, so users can access the org.testifyproject.testifyprojectplete value. Or just use Java
* 8 which has date objects with nanosecond support.
*/
public class DockerDateFormat extends StdDateFormat {
private static final long serialVersionUID = 249048552876483658L;
// either a literal Z or an offset like -04:00 or +1200 with an optional colon separator
private static final String TIMEZONE_PATTERN = "(Z|[+-]\\d{2}:?\\d{2})";
@Override
public Date parse(String source) throws ParseException {
// If the date has nanosecond precision (e.g. 2014-10-17T21:22:56.949763914Z), remove the last
// digits so we can create a Date object, which only support milliseconds.
// Docker doesn't always return nine digits for the fractional seconds part,
// so we need to be more flexible when trimming to milliseconds.
// Also allow for flexible timezone formats, either 'Z' for zulu/UTC or hour offsets.
// StdDateFormat has logic for handling these other timezones, but only if the time portion of
// the string matches hh:mm:ss or hh:mm:ss.SSS
if (source.matches(".+\\.\\d{4,9}" + TIMEZONE_PATTERN + "$")) {
source = source.replaceAll("(\\.\\d{3})\\d{1,6}" + TIMEZONE_PATTERN + "$", "$1$2");
}
return super.parse(source);
}
@Override
@SuppressWarnings("CloneDoesntCallSuperClone")
public DockerDateFormat clone() {
// Normally clone should call super.clone(), but that works only if StdDateFormat calls
// super.clone(), which it does not. We must create a new instance and disable the warning.
return new DockerDateFormat();
}
}