1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20 package org.apache.mina.http;
21
22 import java.text.DateFormat;
23 import java.text.ParseException;
24 import java.text.SimpleDateFormat;
25 import java.util.Calendar;
26 import java.util.Date;
27 import java.util.Locale;
28 import java.util.TimeZone;
29 import java.util.regex.Pattern;
30
31 public class DateUtil {
32
33 private final static Locale LOCALE = Locale.US;
34 private final static TimeZone GMT_ZONE;
35 private final static String RFC_1123_PATTERN = "EEE, dd MMM yyyy HH:mm:ss zzz";
36 private final static DateFormat RFC_1123_FORMAT;
37
38 /** Pattern to find digits only. */
39 private final static Pattern DIGIT_PATTERN = Pattern.compile("^\\d+$");
40
41 static {
42 RFC_1123_FORMAT = new SimpleDateFormat(DateUtil.RFC_1123_PATTERN, DateUtil.LOCALE);
43 GMT_ZONE = TimeZone.getTimeZone("GMT");
44 DateUtil.RFC_1123_FORMAT.setTimeZone(DateUtil.GMT_ZONE);
45 }
46
47 public static String getCurrentAsString() {
48 return DateUtil.RFC_1123_FORMAT.format(new Date()); //NOPMD
49 }
50
51 /**
52 * Translate a given date <code>String</code> in the <em>RFC 1123</em>
53 * format to a <code>long</code> representing the number of milliseconds
54 * since epoch.
55 *
56 * @param dateString a date <code>String</code> in the <em>RFC 1123</em>
57 * format.
58 * @return the parsed <code>Date</code> in milliseconds.
59 */
60 private static long parseDateStringToMilliseconds(final String dateString) {
61
62 try {
63 return DateUtil.RFC_1123_FORMAT.parse(dateString).getTime(); //NOPMD
64 } catch (final ParseException e) {
65 return 0;
66 }
67 }
68
69 /**
70 * Parse a given date <code>String</code> to a <code>long</code>
71 * representation of the time. Where the provided value is all digits the
72 * value is returned as a <code>long</code>, otherwise attempt is made to
73 * parse the <code>String</code> as a <em>RFC 1123</em> date.
74 *
75 * @param dateValue the value to parse.
76 * @return the <code>long</code> value following parse, or zero where not
77 * successful.
78 */
79 public static long parseToMilliseconds(final String dateValue) {
80
81 long ms = 0;
82
83 if (DateUtil.DIGIT_PATTERN.matcher(dateValue).matches()) {
84 ms = Long.parseLong(dateValue);
85 } else {
86 ms = parseDateStringToMilliseconds(dateValue);
87 }
88
89 return ms;
90 }
91
92 /**
93 * Converts a millisecond representation of a date to a
94 * <code>RFC 1123</code> formatted <code>String</code>.
95 *
96 * @param dateValue the <code>Date</code> represented as milliseconds.
97 * @return a <code>String</code> representation of the date.
98 */
99 public static String parseToRFC1123(final long dateValue) {
100
101 final Calendar calendar = Calendar.getInstance();
102 calendar.setTimeInMillis(dateValue);
103
104 return DateUtil.RFC_1123_FORMAT.format(calendar.getTime()); //NOPMD
105 }
106
107 /**
108 * Convert a given <code>Date</code> object to a <code>RFC 1123</code>
109 * formatted <code>String</code>.
110 *
111 * @param date the <code>Date</code> object to convert
112 * @return a <code>String</code> representation of the date.
113 */
114 public static String getDateAsString(Date date) {
115 return RFC_1123_FORMAT.format(date); //NOPMD
116 }
117
118 }