com.spotify.docker.client.DockerDateFormat Maven / Gradle / Ivy
/*
* Copyright (c) 2014 Spotify AB.
*
* 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 com.spotify.docker.client;
import com.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 complete solution would be to introduce a custom date type which can store the
* nanosecond value in an additional field, so users can access the complete value. Or just use
* Java 8 which has date objects with nanosecond support.
*/
public class DockerDateFormat extends StdDateFormat {
private static final long serialVersionUID = 249048552876483658L;
@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
// six digits so we can create a Date object, which only support milliseconds.
if (source.matches(".+\\.\\d{9}Z$")) {
source = source.replaceAll("\\d{6}Z$", "Z");
}
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();
}
}