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