1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18 package org.apache.commons.lang3.time;
19
20 import java.util.Calendar;
21 import java.util.Locale;
22 import java.util.Locale.Category;
23 import java.util.Map;
24 import java.util.Objects;
25
26 /**
27 * Helps use {@link Calendar}s.
28 *
29 * @since 3.10
30 */
31 public class CalendarUtils {
32
33 /**
34 * The singleton instance for {@link Calendar#getInstance()}. The instance is created when the class is initialized and is based on the current time in the
35 * default time zone with the default {@link Category#FORMAT} locale.
36 *
37 * @see CalendarUtils#getInstance()
38 */
39 public static final CalendarUtils INSTANCE = getInstance();
40
41 /**
42 * Creates a new instance based on the current time in the default time zone with the default {@link Category#FORMAT} locale.
43 *
44 * @return a new instance.
45 * @since 3.14.0
46 */
47 public static CalendarUtils getInstance() {
48 return new CalendarUtils(Calendar.getInstance());
49 }
50
51 /**
52 * Gets a CalendarUtils using the default time zone and specified locale. The <code>CalendarUtils</code> returned is based on the current time in the
53 * default time zone with the given locale.
54 *
55 * @param locale the locale for the week data
56 * @return a Calendar.
57 */
58 static CalendarUtils getInstance(final Locale locale) {
59 return new CalendarUtils(Calendar.getInstance(locale), locale);
60 }
61
62 private final Calendar calendar;
63
64 private final Locale locale;
65
66 /**
67 * Creates an instance for the given Calendar.
68 *
69 * @param calendar A Calendar.
70 */
71 public CalendarUtils(final Calendar calendar) {
72 this(calendar, Locale.getDefault());
73 }
74
75 /**
76 * Creates an instance for the given Calendar.
77 *
78 * @param calendar A Calendar.
79 * @param locale A Locale.
80 */
81 CalendarUtils(final Calendar calendar, final Locale locale) {
82 this.calendar = Objects.requireNonNull(calendar, "calendar");
83 this.locale = Objects.requireNonNull(locale, "locale");
84 }
85 /**
86 * Gets the current day of month.
87 *
88 * @return the current day of month.
89 */
90 public int getDayOfMonth() {
91 return calendar.get(Calendar.DAY_OF_MONTH);
92 }
93
94 /**
95 * Gets the current day of year.
96 *
97 * @return the current day of year.
98 * @since 3.13.0
99 */
100 public int getDayOfYear() {
101 return calendar.get(Calendar.DAY_OF_YEAR);
102 }
103
104 /**
105 * Gets the current month.
106 *
107 * @return the current month.
108 */
109 public int getMonth() {
110 return calendar.get(Calendar.MONTH);
111 }
112
113 /**
114 * Gets month names in the requested style.
115 * @param style Must be a valid {@link Calendar#getDisplayNames(int, int, Locale)} month style.
116 * @return Styled names of months
117 */
118 String[] getMonthDisplayNames(final int style) {
119 // Unfortunately standalone month names are not available in DateFormatSymbols,
120 // so we have to extract them.
121 final Map<String, Integer> displayNames = calendar.getDisplayNames(Calendar.MONTH, style, locale);
122 if (displayNames == null) {
123 return null;
124 }
125 final String[] monthNames = new String[displayNames.size()];
126 displayNames.forEach((k, v) -> monthNames[v] = k);
127 return monthNames;
128 }
129
130 /**
131 * Gets full standalone month names as used in "LLLL" date formatting.
132 * @return Long names of months
133 */
134 String[] getStandaloneLongMonthNames() {
135 return getMonthDisplayNames(Calendar.LONG_STANDALONE);
136 }
137
138 /**
139 * Gets short standalone month names as used in "LLLL" date formatting.
140 * @return Short names of months
141 */
142 String[] getStandaloneShortMonthNames() {
143 return getMonthDisplayNames(Calendar.SHORT_STANDALONE);
144 }
145
146 /**
147 * Gets the current year.
148 *
149 * @return the current year.
150 */
151 public int getYear() {
152 return calendar.get(Calendar.YEAR);
153 }
154 }