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 */
017package org.apache.juneau.http.header;
018
019import static java.time.format.DateTimeFormatter.*;
020import static java.time.temporal.ChronoUnit.*;
021
022import java.time.*;
023import java.util.*;
024import java.util.function.*;
025
026import org.apache.juneau.assertions.*;
027import org.apache.juneau.common.utils.*;
028
029/**
030 * Category of headers that consist of a single HTTP-date.
031 *
032 * <p>
033 * <h5 class='figure'>Example</h5>
034 * <p class='bcode'>
035 *    If-Modified-Since: Sat, 29 Oct 1994 19:43:31 GMT
036 * </p>
037 *
038 * <h5 class='section'>See Also:</h5><ul>
039 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/JuneauRestCommonBasics">juneau-rest-common Basics</a>
040 *    <li class='extlink'><a class="doclink" href="https://www.w3.org/Protocols/rfc2616/rfc2616.html">Hypertext Transfer Protocol -- HTTP/1.1</a>
041 * </ul>
042 *
043 * @serial exclude
044 */
045public class BasicDateHeader extends BasicHeader {
046
047   //-----------------------------------------------------------------------------------------------------------------
048   // Static
049   //-----------------------------------------------------------------------------------------------------------------
050
051   private static final long serialVersionUID = 1L;
052
053   /**
054    * Static creator.
055    *
056    * @param name The header name.
057    * @param value
058    *    The header value.
059    *    <br>Must be an RFC-1123 formated string (e.g. <js>"Sat, 29 Oct 1994 19:43:31 GMT"</js>).
060    *    <br>Can be <jk>null</jk>.
061    * @return A new header bean, or <jk>null</jk> if the value is <jk>null</jk>.
062    * @throws IllegalArgumentException If name is <jk>null</jk> or empty.
063    */
064   public static BasicDateHeader of(String name, String value) {
065      return value == null ? null : new BasicDateHeader(name, value);
066   }
067
068   /**
069    * Static creator.
070    *
071    * @param name The header name.
072    * @param value
073    *    The header value.
074    *    <br>Can be <jk>null</jk>.
075    * @return A new header bean, or <jk>null</jk> if the value is <jk>null</jk>.
076    * @throws IllegalArgumentException If name is <jk>null</jk> or empty.
077    */
078   public static BasicDateHeader of(String name, ZonedDateTime value) {
079      return value == null ? null : new BasicDateHeader(name, value);
080   }
081
082   /**
083    * Static creator with delayed value.
084    *
085    * <p>
086    * Header value is re-evaluated on each call to {@link #getValue()}.
087    *
088    * @param name The header name.
089    * @param value
090    *    The supplier of the header value.
091    *    <br>Can be <jk>null</jk>.
092    * @return A new header bean, or <jk>null</jk> if the value is <jk>null</jk>.
093    * @throws IllegalArgumentException If name is <jk>null</jk> or empty.
094    */
095   public static BasicDateHeader of(String name, Supplier<ZonedDateTime> value) {
096      return value == null ? null : new BasicDateHeader(name, value);
097   }
098
099   //-----------------------------------------------------------------------------------------------------------------
100   // Instance
101   //-----------------------------------------------------------------------------------------------------------------
102
103   private final ZonedDateTime value;
104   private final Supplier<ZonedDateTime> supplier;
105
106   /**
107    * Constructor.
108    *
109    * @param name The header name.
110    * @param value
111    *    The header value.
112    *    <br>Must be an RFC-1123 formated string (e.g. <js>"Sat, 29 Oct 1994 19:43:31 GMT"</js>).
113    *    <br>Can be <jk>null</jk>.
114    * @throws IllegalArgumentException If name is <jk>null</jk> or empty.
115    */
116   public BasicDateHeader(String name, String value) {
117      super(name, value);
118      this.value = Utils.isEmpty(value) ? null : ZonedDateTime.from(RFC_1123_DATE_TIME.parse(value.toString())).truncatedTo(SECONDS);
119      this.supplier = null;
120   }
121
122   /**
123    * Constructor.
124    *
125    * @param name The header name.
126    * @param value
127    *    The header value.
128    *    <br>Can be <jk>null</jk>.
129    * @throws IllegalArgumentException If name is <jk>null</jk> or empty.
130    */
131   public BasicDateHeader(String name, ZonedDateTime value) {
132      super(name, value);
133      this.value = value;
134      this.supplier = null;
135   }
136
137   /**
138    * Constructor with delayed value.
139    *
140    * <p>
141    * Header value is re-evaluated on each call to {@link #getValue()}.
142    *
143    * @param name The header name.
144    * @param value
145    *    The supplier of the header value.
146    *    <br>Can be <jk>null</jk>.
147    * @throws IllegalArgumentException If name is <jk>null</jk> or empty.
148    */
149   public BasicDateHeader(String name, Supplier<ZonedDateTime> value) {
150      super(name, null);
151      this.value = null;
152      this.supplier = value;
153   }
154
155   @Override /* Header */
156   public String getValue() {
157      ZonedDateTime x = value();
158      return x == null ? null : RFC_1123_DATE_TIME.format(x);
159   }
160
161   /**
162    * Returns the header value as a {@link ZonedDateTime} wrapped in an {@link Optional}.
163    *
164    * @return The header value as a {@link ZonedDateTime} wrapped in an {@link Optional}.  Never <jk>null</jk>.
165    */
166   public Optional<ZonedDateTime> asZonedDateTime() {
167      return Utils.opt(value());
168   }
169
170   /**
171    * Returns the header value as a {@link ZonedDateTime}.
172    *
173    * @return The header value as a {@link ZonedDateTime}.  Can be <jk>null</jk>.
174    */
175   public ZonedDateTime toZonedDateTime() {
176      return value();
177   }
178
179   /**
180    * Provides the ability to perform fluent-style assertions on this header.
181    *
182    * <h5 class='section'>Examples:</h5>
183    * <p class='bjava'>
184    *    <jc>// Validates the response body content is not expired.</jc>
185    *    <jv>client</jv>
186    *       .get(<jsf>URL</jsf>)
187    *       .run()
188    *       .getHeader(<js>"Expires"</js>).asDateHeader().assertZonedDateTime().isLessThan(<jk>new</jk> Date());
189    * </p>
190    *
191    * @return A new fluent assertion object.
192    * @throws AssertionError If assertion failed.
193    */
194   public FluentZonedDateTimeAssertion<BasicDateHeader> assertZonedDateTime() {
195      return new FluentZonedDateTimeAssertion<>(value(), this);
196   }
197
198   /**
199    * Return the value if present, otherwise return <c>other</c>.
200    *
201    * <p>
202    * This is a shortened form for calling <c>asZonedDateTime().orElse(<jv>other</jv>)</c>.
203    *
204    * @param other The value to be returned if there is no value present, can be <jk>null</jk>.
205    * @return The value, if present, otherwise <c>other</c>.
206    */
207   public ZonedDateTime orElse(ZonedDateTime other) {
208      ZonedDateTime x = value();
209      return x != null ? x : other;
210   }
211
212   private ZonedDateTime value() {
213      if (supplier != null)
214         return supplier.get();
215      return value;
216   }
217}