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 package org.apache.commons.lang3.time;
18
19 import java.text.DateFormat;
20 import java.text.Format;
21 import java.text.SimpleDateFormat;
22 import java.util.Arrays;
23 import java.util.Locale;
24 import java.util.Objects;
25 import java.util.TimeZone;
26 import java.util.concurrent.ConcurrentHashMap;
27 import java.util.concurrent.ConcurrentMap;
28
29 import org.apache.commons.lang3.LocaleUtils;
30
31 /**
32 * FormatCache is a cache and factory for {@link Format}s.
33 *
34 * @param <F> The Format type.
35 *
36 * @since 3.0
37 */
38 // TODO: Before making public move from getDateTimeInstance(Integer, ...) to int; or some other approach.
39 abstract class AbstractFormatCache<F extends Format> {
40
41 /**
42 * Helper class to hold multipart Map keys as arrays.
43 */
44 private static final class ArrayKey {
45
46 private static int computeHashCode(final Object[] keys) {
47 final int prime = 31;
48 int result = 1;
49 result = prime * result + Arrays.hashCode(keys);
50 return result;
51 }
52
53 private final Object[] keys;
54 private final int hashCode;
55
56 /**
57 * Constructs an instance of {@link MultipartKey} to hold the specified objects.
58 *
59 * @param keys the set of objects that make up the key. Each key may be null.
60 */
61 ArrayKey(final Object... keys) {
62 this.keys = keys;
63 this.hashCode = computeHashCode(keys);
64 }
65
66 @Override
67 public boolean equals(final Object obj) {
68 if (this == obj) {
69 return true;
70 }
71 if (obj == null) {
72 return false;
73 }
74 if (getClass() != obj.getClass()) {
75 return false;
76 }
77 final ArrayKey other = (ArrayKey) obj;
78 return Arrays.deepEquals(keys, other.keys);
79 }
80
81 @Override
82 public int hashCode() {
83 return hashCode;
84 }
85
86 }
87
88 /**
89 * No date or no time. Used in same parameters as DateFormat.SHORT or DateFormat.LONG
90 */
91 static final int NONE = -1;
92
93 private static final ConcurrentMap<ArrayKey, String> cDateTimeInstanceCache = new ConcurrentHashMap<>(7);
94
95 /**
96 * Gets a date/time format for the specified styles and locale.
97 *
98 * @param dateStyle date style: FULL, LONG, MEDIUM, or SHORT, null indicates no date in format
99 * @param timeStyle time style: FULL, LONG, MEDIUM, or SHORT, null indicates no time in format
100 * @param locale The non-null locale of the desired format
101 * @return a localized standard date/time format
102 * @throws IllegalArgumentException if the Locale has no date/time pattern defined
103 */
104 // package protected, for access from test code; do not make public or protected
105 static String getPatternForStyle(final Integer dateStyle, final Integer timeStyle, final Locale locale) {
106 final Locale safeLocale = LocaleUtils.toLocale(locale);
107 final ArrayKey key = new ArrayKey(dateStyle, timeStyle, safeLocale);
108 return cDateTimeInstanceCache.computeIfAbsent(key, k -> {
109 try {
110 final DateFormat formatter;
111 if (dateStyle == null) {
112 formatter = DateFormat.getTimeInstance(timeStyle.intValue(), safeLocale);
113 } else if (timeStyle == null) {
114 formatter = DateFormat.getDateInstance(dateStyle.intValue(), safeLocale);
115 } else {
116 formatter = DateFormat.getDateTimeInstance(dateStyle.intValue(), timeStyle.intValue(), safeLocale);
117 }
118 return ((SimpleDateFormat) formatter).toPattern();
119 } catch (final ClassCastException ex) {
120 throw new IllegalArgumentException("No date time pattern for locale: " + safeLocale);
121 }
122 });
123 }
124
125 private final ConcurrentMap<ArrayKey, F> cInstanceCache = new ConcurrentHashMap<>(7);
126
127 /**
128 * Create a format instance using the specified pattern, time zone
129 * and locale.
130 *
131 * @param pattern {@link java.text.SimpleDateFormat} compatible pattern, this will not be null.
132 * @param timeZone time zone, this will not be null.
133 * @param locale locale, this will not be null.
134 * @return a pattern based date/time formatter
135 * @throws IllegalArgumentException if pattern is invalid
136 * or {@code null}
137 */
138 protected abstract F createInstance(String pattern, TimeZone timeZone, Locale locale);
139
140 /**
141 * Gets a date formatter instance using the specified style,
142 * time zone and locale.
143 *
144 * @param dateStyle date style: FULL, LONG, MEDIUM, or SHORT
145 * @param timeZone optional time zone, overrides time zone of
146 * formatted date, null means use default Locale
147 * @param locale optional locale, overrides system locale
148 * @return a localized standard date/time formatter
149 * @throws IllegalArgumentException if the Locale has no date/time
150 * pattern defined
151 */
152 // package protected, for access from FastDateFormat; do not make public or protected
153 F getDateInstance(final int dateStyle, final TimeZone timeZone, final Locale locale) {
154 return getDateTimeInstance(Integer.valueOf(dateStyle), null, timeZone, locale);
155 }
156
157 /**
158 * Gets a date/time formatter instance using the specified style,
159 * time zone and locale.
160 *
161 * @param dateStyle date style: FULL, LONG, MEDIUM, or SHORT
162 * @param timeStyle time style: FULL, LONG, MEDIUM, or SHORT
163 * @param timeZone optional time zone, overrides time zone of
164 * formatted date, null means use default Locale
165 * @param locale optional locale, overrides system locale
166 * @return a localized standard date/time formatter
167 * @throws IllegalArgumentException if the Locale has no date/time
168 * pattern defined
169 */
170 // package protected, for access from FastDateFormat; do not make public or protected
171 F getDateTimeInstance(final int dateStyle, final int timeStyle, final TimeZone timeZone, final Locale locale) {
172 return getDateTimeInstance(Integer.valueOf(dateStyle), Integer.valueOf(timeStyle), timeZone, locale);
173 }
174
175 /**
176 * Gets a date/time formatter instance using the specified style,
177 * time zone and locale.
178 *
179 * @param dateStyle date style: FULL, LONG, MEDIUM, or SHORT, null indicates no date in format
180 * @param timeStyle time style: FULL, LONG, MEDIUM, or SHORT, null indicates no time in format
181 * @param timeZone optional time zone, overrides time zone of
182 * formatted date, null means use default Locale
183 * @param locale optional locale, overrides system locale
184 * @return a localized standard date/time formatter
185 * @throws IllegalArgumentException if the Locale has no date/time
186 * pattern defined
187 */
188 // This must remain private, see LANG-884
189 private F getDateTimeInstance(final Integer dateStyle, final Integer timeStyle, final TimeZone timeZone, Locale locale) {
190 locale = LocaleUtils.toLocale(locale);
191 final String pattern = getPatternForStyle(dateStyle, timeStyle, locale);
192 return getInstance(pattern, timeZone, locale);
193 }
194
195 /**
196 * Gets a formatter instance using the default pattern in the
197 * default time zone and locale.
198 *
199 * @return a date/time formatter
200 */
201 public F getInstance() {
202 return getDateTimeInstance(DateFormat.SHORT, DateFormat.SHORT, TimeZone.getDefault(), Locale.getDefault());
203 }
204
205 /**
206 * Gets a formatter instance using the specified pattern, time zone
207 * and locale.
208 *
209 * @param pattern {@link java.text.SimpleDateFormat} compatible
210 * pattern, non-null
211 * @param timeZone the time zone, null means use the default TimeZone
212 * @param locale the locale, null means use the default Locale
213 * @return a pattern based date/time formatter
214 * @throws NullPointerException if pattern is {@code null}
215 * @throws IllegalArgumentException if pattern is invalid
216 */
217 public F getInstance(final String pattern, final TimeZone timeZone, final Locale locale) {
218 Objects.requireNonNull(pattern, "pattern");
219 final TimeZone actualTimeZone = TimeZones.toTimeZone(timeZone);
220 final Locale actualLocale = LocaleUtils.toLocale(locale);
221 final ArrayKey key = new ArrayKey(pattern, actualTimeZone, actualLocale);
222 return cInstanceCache.computeIfAbsent(key, k -> createInstance(pattern, actualTimeZone, actualLocale));
223 }
224
225 /**
226 * Gets a time formatter instance using the specified style,
227 * time zone and locale.
228 *
229 * @param timeStyle time style: FULL, LONG, MEDIUM, or SHORT
230 * @param timeZone optional time zone, overrides time zone of
231 * formatted date, null means use default Locale
232 * @param locale optional locale, overrides system locale
233 * @return a localized standard date/time formatter
234 * @throws IllegalArgumentException if the Locale has no date/time
235 * pattern defined
236 */
237 // package protected, for access from FastDateFormat; do not make public or protected
238 F getTimeInstance(final int timeStyle, final TimeZone timeZone, final Locale locale) {
239 return getDateTimeInstance(null, Integer.valueOf(timeStyle), timeZone, locale);
240 }
241
242 }