1 /*
2 * Copyright 2001-2009 Stephen Colebourne
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package org.joda.time.convert;
17
18 import java.util.Calendar;
19 import java.util.GregorianCalendar;
20
21 import org.joda.time.Chronology;
22 import org.joda.time.DateTimeZone;
23 import org.joda.time.chrono.BuddhistChronology;
24 import org.joda.time.chrono.GJChronology;
25 import org.joda.time.chrono.GregorianChronology;
26 import org.joda.time.chrono.ISOChronology;
27 import org.joda.time.chrono.JulianChronology;
28
29 /**
30 * CalendarConverter converts a java util Calendar to an instant or partial.
31 * The Calendar is converted to milliseconds and the chronology that best
32 * matches the calendar.
33 *
34 * @author Stephen Colebourne
35 * @since 1.0
36 */
37 final class CalendarConverter extends AbstractConverter
38 implements InstantConverter, PartialConverter {
39
40 /**
41 * Singleton instance.
42 */
43 static final CalendarConverter INSTANCE = new CalendarConverter();
44
45 /**
46 * Restricted constructor.
47 */
48 protected CalendarConverter() {
49 super();
50 }
51
52 //-----------------------------------------------------------------------
53 /**
54 * Gets the chronology.
55 * <p>
56 * If a chronology is specified then it is used.
57 * Otherwise, it is the GJChronology if a GregorianCalendar is used,
58 * BuddhistChronology if a BuddhistCalendar is used or ISOChronology otherwise.
59 * The time zone is extracted from the calendar if possible, default used if not.
60 *
61 * @param object the Calendar to convert, must not be null
62 * @param chrono the chronology to use, null means use Calendar
63 * @return the chronology, never null
64 * @throws NullPointerException if the object is null
65 * @throws ClassCastException if the object is an invalid type
66 */
67 public Chronology getChronology(Object object, Chronology chrono) {
68 if (chrono != null) {
69 return chrono;
70 }
71 Calendar cal = (Calendar) object;
72 DateTimeZone zone = null;
73 try {
74 zone = DateTimeZone.forTimeZone(cal.getTimeZone());
75
76 } catch (IllegalArgumentException ex) {
77 zone = DateTimeZone.getDefault();
78 }
79 return getChronology(cal, zone);
80 }
81
82 /**
83 * Gets the chronology, which is the GJChronology if a GregorianCalendar is used,
84 * BuddhistChronology if a BuddhistCalendar is used or ISOChronology otherwise.
85 * The time zone specified is used in preference to that on the calendar.
86 *
87 * @param object the Calendar to convert, must not be null
88 * @param zone the specified zone to use, null means default zone
89 * @return the chronology, never null
90 * @throws NullPointerException if the object is null
91 * @throws ClassCastException if the object is an invalid type
92 */
93 public Chronology getChronology(Object object, DateTimeZone zone) {
94 if (object.getClass().getName().endsWith(".BuddhistCalendar")) {
95 return BuddhistChronology.getInstance(zone);
96 } else if (object instanceof GregorianCalendar) {
97 GregorianCalendar gc = (GregorianCalendar) object;
98 long cutover = gc.getGregorianChange().getTime();
99 if (cutover == Long.MIN_VALUE) {
100 return GregorianChronology.getInstance(zone);
101 } else if (cutover == Long.MAX_VALUE) {
102 return JulianChronology.getInstance(zone);
103 } else {
104 return GJChronology.getInstance(zone, cutover, 4);
105 }
106 } else {
107 return ISOChronology.getInstance(zone);
108 }
109 }
110
111 /**
112 * Gets the millis, which is the Calendar millis value.
113 *
114 * @param object the Calendar to convert, must not be null
115 * @param chrono the chronology result from getChronology, non-null
116 * @return the millisecond value
117 * @throws NullPointerException if the object is null
118 * @throws ClassCastException if the object is an invalid type
119 */
120 public long getInstantMillis(Object object, Chronology chrono) {
121 Calendar calendar = (Calendar) object;
122 return calendar.getTime().getTime();
123 }
124
125 //-----------------------------------------------------------------------
126 /**
127 * Returns Calendar.class.
128 *
129 * @return Calendar.class
130 */
131 public Class<?> getSupportedType() {
132 return Calendar.class;
133 }
134
135 }