1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27 package org.apache.hc.client5.http.impl.cache;
28
29 import java.time.Instant;
30
31 import org.apache.hc.client5.http.utils.DateUtils;
32 import org.apache.hc.core5.annotation.Internal;
33 import org.apache.hc.core5.http.Header;
34 import org.apache.hc.core5.http.MessageHeaders;
35
36 /**
37 * HTTP cache date support utilities.
38 *
39 * @since 5.2
40 */
41 @Internal
42 public final class DateSupport {
43
44 /**
45 * Tests if the first message is after (newer) than second one
46 * using the given message header for comparison.
47 *
48 * @param message1 the first message
49 * @param message2 the second message
50 * @param headerName header name
51 *
52 * @return {@code true} if both messages contain a header with the given name
53 * and the value of the header from the first message is newer that of
54 * the second message.
55 *
56 * @since 5.0
57 */
58 public static boolean isAfter(
59 final MessageHeaders message1,
60 final MessageHeaders message2,
61 final String headerName) {
62 if (message1 != null && message2 != null) {
63 final Header dateHeader1 = message1.getFirstHeader(headerName);
64 if (dateHeader1 != null) {
65 final Header dateHeader2 = message2.getFirstHeader(headerName);
66 if (dateHeader2 != null) {
67 final Instant date1 = DateUtils.parseStandardDate(dateHeader1.getValue());
68 if (date1 != null) {
69 final Instant date2 = DateUtils.parseStandardDate(dateHeader2.getValue());
70 if (date2 != null) {
71 return date1.isAfter(date2);
72 }
73 }
74 }
75 }
76 }
77 return false;
78 }
79
80 /**
81 * Tests if the first message is before (older) than the second one
82 * using the given message header for comparison.
83 *
84 * @param message1 the first message
85 * @param message2 the second message
86 * @param headerName header name
87 *
88 * @return {@code true} if both messages contain a header with the given name
89 * and the value of the header from the first message is older that of
90 * the second message.
91 *
92 * @since 5.0
93 */
94 public static boolean isBefore(
95 final MessageHeaders message1,
96 final MessageHeaders message2,
97 final String headerName) {
98 if (message1 != null && message2 != null) {
99 final Header dateHeader1 = message1.getFirstHeader(headerName);
100 if (dateHeader1 != null) {
101 final Header dateHeader2 = message2.getFirstHeader(headerName);
102 if (dateHeader2 != null) {
103 final Instant date1 = DateUtils.parseStandardDate(dateHeader1.getValue());
104 if (date1 != null) {
105 final Instant date2 = DateUtils.parseStandardDate(dateHeader2.getValue());
106 if (date2 != null) {
107 return date1.isBefore(date2);
108 }
109 }
110 }
111 }
112 }
113 return false;
114 }
115
116 }