| 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 org.joda.time.DurationFieldType; |
| 19 | |
| 20 | /** |
| 21 | * Duration field class representing a field with a fixed unit length. |
| 22 | * <p> |
| 23 | * PreciseDurationField is thread-safe and immutable. |
| 24 | * |
| 25 | * @author Stephen Colebourne |
| 26 | * @author Brian S O'Neill |
| 27 | * @since 1.0 |
| 28 | */ |
| 29 | public class PreciseDurationField extends BaseDurationField { |
| 30 | |
| 31 | private static final long serialVersionUID = -8346152187724495365L; |
| 32 | |
| 33 | /** The size of the unit */ |
| 34 | private final long iUnitMillis; |
| 35 | |
| 36 | /** |
| 37 | * Constructor. |
| 38 | * |
| 39 | * @param type the field type |
| 40 | * @param unitMillis the unit milliseconds |
| 41 | */ |
| 42 | public PreciseDurationField(DurationFieldType type, long unitMillis) { |
| 43 | super(type); |
| 44 | iUnitMillis = unitMillis; |
| 45 | } |
| 46 | |
| 47 | //------------------------------------------------------------------------ |
| 48 | /** |
| 49 | * This field is precise. |
| 50 | * |
| 51 | * @return true always |
| 52 | */ |
| 53 | public final boolean isPrecise() { |
| 54 | return true; |
| 55 | } |
| 56 | |
| 57 | /** |
| 58 | * Returns the amount of milliseconds per unit value of this field. |
| 59 | * |
| 60 | * @return the unit size of this field, in milliseconds |
| 61 | */ |
| 62 | public final long getUnitMillis() { |
| 63 | return iUnitMillis; |
| 64 | } |
| 65 | |
| 66 | //------------------------------------------------------------------------ |
| 67 | /** |
| 68 | * Get the value of this field from the milliseconds. |
| 69 | * |
| 70 | * @param duration the milliseconds to query, which may be negative |
| 71 | * @param instant ignored |
| 72 | * @return the value of the field, in the units of the field, which may be |
| 73 | * negative |
| 74 | */ |
| 75 | public long getValueAsLong(long duration, long instant) { |
| 76 | return duration / iUnitMillis; // safe |
| 77 | } |
| 78 | |
| 79 | /** |
| 80 | * Get the millisecond duration of this field from its value. |
| 81 | * |
| 82 | * @param value the value of the field, which may be negative |
| 83 | * @param instant ignored |
| 84 | * @return the milliseconds that the field represents, which may be |
| 85 | * negative |
| 86 | */ |
| 87 | public long getMillis(int value, long instant) { |
| 88 | return value * iUnitMillis; // safe |
| 89 | } |
| 90 | |
| 91 | /** |
| 92 | * Get the millisecond duration of this field from its value. |
| 93 | * |
| 94 | * @param value the value of the field, which may be negative |
| 95 | * @param instant ignored |
| 96 | * @return the milliseconds that the field represents, which may be |
| 97 | * negative |
| 98 | */ |
| 99 | public long getMillis(long value, long instant) { |
| 100 | return FieldUtils.safeMultiply(value, iUnitMillis); |
| 101 | } |
| 102 | |
| 103 | public long add(long instant, int value) { |
| 104 | long addition = value * iUnitMillis; // safe |
| 105 | return FieldUtils.safeAdd(instant, addition); |
| 106 | } |
| 107 | |
| 108 | public long add(long instant, long value) { |
| 109 | long addition = FieldUtils.safeMultiply(value, iUnitMillis); |
| 110 | return FieldUtils.safeAdd(instant, addition); |
| 111 | } |
| 112 | |
| 113 | public long getDifferenceAsLong(long minuendInstant, long subtrahendInstant) { |
| 114 | long difference = FieldUtils.safeSubtract(minuendInstant, subtrahendInstant); |
| 115 | return difference / iUnitMillis; |
| 116 | } |
| 117 | |
| 118 | //----------------------------------------------------------------------- |
| 119 | /** |
| 120 | * Compares this duration field to another. |
| 121 | * Two fields are equal if of the same type and duration. |
| 122 | * |
| 123 | * @param obj the object to compare to |
| 124 | * @return if equal |
| 125 | */ |
| 126 | public boolean equals(Object obj) { |
| 127 | if (this == obj) { |
| 128 | return true; |
| 129 | } else if (obj instanceof PreciseDurationField) { |
| 130 | PreciseDurationField other = (PreciseDurationField) obj; |
| 131 | return (getType() == other.getType()) && (iUnitMillis == other.iUnitMillis); |
| 132 | } |
| 133 | return false; |
| 134 | } |
| 135 | |
| 136 | /** |
| 137 | * Gets a hash code for this instance. |
| 138 | * |
| 139 | * @return a suitable hashcode |
| 140 | */ |
| 141 | public int hashCode() { |
| 142 | long millis = iUnitMillis; |
| 143 | int hash = (int) (millis ^ (millis >>> 32)); |
| 144 | hash += getType().hashCode(); |
| 145 | return hash; |
| 146 | } |
| 147 | |
| 148 | } |