1 | /* |
2 | * Copyright 2001-2005 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.field; |
17 | |
18 | import java.io.Serializable; |
19 | |
20 | import org.joda.time.DurationField; |
21 | import org.joda.time.DurationFieldType; |
22 | |
23 | /** |
24 | * Duration field class representing a field with a fixed unit length of one |
25 | * millisecond. |
26 | * <p> |
27 | * MillisDurationField is thread-safe and immutable. |
28 | * |
29 | * @author Brian S O'Neill |
30 | * @since 1.0 |
31 | */ |
32 | public final class MillisDurationField extends DurationField implements Serializable { |
33 | |
34 | /** Serialization lock. */ |
35 | private static final long serialVersionUID = 2656707858124633367L; |
36 | |
37 | /** Singleton instance. */ |
38 | public static final DurationField INSTANCE = new MillisDurationField(); |
39 | |
40 | /** |
41 | * Restricted constructor. |
42 | */ |
43 | private MillisDurationField() { |
44 | super(); |
45 | } |
46 | |
47 | //------------------------------------------------------------------------ |
48 | public DurationFieldType getType() { |
49 | return DurationFieldType.millis(); |
50 | } |
51 | |
52 | public String getName() { |
53 | return "millis"; |
54 | } |
55 | |
56 | /** |
57 | * Returns true as this field is supported. |
58 | * |
59 | * @return true always |
60 | */ |
61 | public boolean isSupported() { |
62 | return true; |
63 | } |
64 | |
65 | /** |
66 | * Returns true as this field is precise. |
67 | * |
68 | * @return true always |
69 | */ |
70 | public final boolean isPrecise() { |
71 | return true; |
72 | } |
73 | |
74 | /** |
75 | * Returns the amount of milliseconds per unit value of this field. |
76 | * |
77 | * @return one always |
78 | */ |
79 | public final long getUnitMillis() { |
80 | return 1; |
81 | } |
82 | |
83 | //------------------------------------------------------------------------ |
84 | public int getValue(long duration) { |
85 | return FieldUtils.safeToInt(duration); |
86 | } |
87 | |
88 | public long getValueAsLong(long duration) { |
89 | return duration; |
90 | } |
91 | |
92 | public int getValue(long duration, long instant) { |
93 | return FieldUtils.safeToInt(duration); |
94 | } |
95 | |
96 | public long getValueAsLong(long duration, long instant) { |
97 | return duration; |
98 | } |
99 | |
100 | public long getMillis(int value) { |
101 | return value; |
102 | } |
103 | |
104 | public long getMillis(long value) { |
105 | return value; |
106 | } |
107 | |
108 | public long getMillis(int value, long instant) { |
109 | return value; |
110 | } |
111 | |
112 | public long getMillis(long value, long instant) { |
113 | return value; |
114 | } |
115 | |
116 | public long add(long instant, int value) { |
117 | return FieldUtils.safeAdd(instant, value); |
118 | } |
119 | |
120 | public long add(long instant, long value) { |
121 | return FieldUtils.safeAdd(instant, value); |
122 | } |
123 | |
124 | public int getDifference(long minuendInstant, long subtrahendInstant) { |
125 | return FieldUtils.safeToInt(FieldUtils.safeSubtract(minuendInstant, subtrahendInstant)); |
126 | } |
127 | |
128 | public long getDifferenceAsLong(long minuendInstant, long subtrahendInstant) { |
129 | return FieldUtils.safeSubtract(minuendInstant, subtrahendInstant); |
130 | } |
131 | |
132 | //------------------------------------------------------------------------ |
133 | public int compareTo(Object durationField) { |
134 | DurationField otherField = (DurationField) durationField; |
135 | long otherMillis = otherField.getUnitMillis(); |
136 | long thisMillis = getUnitMillis(); |
137 | // cannot do (thisMillis - otherMillis) as can overflow |
138 | if (thisMillis == otherMillis) { |
139 | return 0; |
140 | } |
141 | if (thisMillis < otherMillis) { |
142 | return -1; |
143 | } else { |
144 | return 1; |
145 | } |
146 | } |
147 | |
148 | /** |
149 | * Get a suitable debug string. |
150 | * |
151 | * @return debug string |
152 | */ |
153 | public String toString() { |
154 | return "DurationField[millis]"; |
155 | } |
156 | |
157 | /** |
158 | * Deserialize to the singleton. |
159 | */ |
160 | private Object readResolve() { |
161 | return INSTANCE; |
162 | } |
163 | |
164 | } |