/*
* Copyright 2001-2005 Stephen Colebourne
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.joda.time.field;
import org.joda.time.DurationFieldType;
/**
* Duration field class representing a field with a fixed unit length.
* <p>
* PreciseDurationField is thread-safe and immutable.
*
* @author Stephen Colebourne
* @author Brian S O'Neill
* @since 1.0
*/
public class PreciseDurationField extends BaseDurationField {
private static final long serialVersionUID = -8346152187724495365L;
/** The size of the unit */
private final long iUnitMillis;
/**
* Constructor.
*
* @param type the field type
* @param unitMillis the unit milliseconds
*/
public PreciseDurationField(DurationFieldType type, long unitMillis) {
super(type);
iUnitMillis = unitMillis;
}
//------------------------------------------------------------------------
/**
* This field is precise.
*
* @return true always
*/
public final boolean isPrecise() {
return true;
}
/**
* Returns the amount of milliseconds per unit value of this field.
*
* @return the unit size of this field, in milliseconds
*/
public final long getUnitMillis() {
return iUnitMillis;
}
//------------------------------------------------------------------------
/**
* Get the value of this field from the milliseconds.
*
* @param duration the milliseconds to query, which may be negative
* @param instant ignored
* @return the value of the field, in the units of the field, which may be
* negative
*/
public long getValueAsLong(long duration, long instant) {
return duration / iUnitMillis; // safe
}
/**
* Get the millisecond duration of this field from its value.
*
* @param value the value of the field, which may be negative
* @param instant ignored
* @return the milliseconds that the field represents, which may be
* negative
*/
public long getMillis(int value, long instant) {
return value * iUnitMillis; // safe
}
/**
* Get the millisecond duration of this field from its value.
*
* @param value the value of the field, which may be negative
* @param instant ignored
* @return the milliseconds that the field represents, which may be
* negative
*/
public long getMillis(long value, long instant) {
return FieldUtils.safeMultiply(value, iUnitMillis);
}
public long add(long instant, int value) {
long addition = value * iUnitMillis; // safe
return FieldUtils.safeAdd(instant, addition);
}
public long add(long instant, long value) {
long addition = FieldUtils.safeMultiply(value, iUnitMillis);
return FieldUtils.safeAdd(instant, addition);
}
public long getDifferenceAsLong(long minuendInstant, long subtrahendInstant) {
long difference = FieldUtils.safeSubtract(minuendInstant, subtrahendInstant);
return difference / iUnitMillis;
}
//-----------------------------------------------------------------------
/**
* Compares this duration field to another.
* Two fields are equal if of the same type and duration.
*
* @param obj the object to compare to
* @return if equal
*/
public boolean equals(Object obj) {
if (this == obj) {
return true;
} else if (obj instanceof PreciseDurationField) {
PreciseDurationField other = (PreciseDurationField) obj;
return (getType() == other.getType()) && (iUnitMillis == other.iUnitMillis);
}
return false;
}
/**
* Gets a hash code for this instance.
*
* @return a suitable hashcode
*/
public int hashCode() {
long millis = iUnitMillis;
int hash = (int) (millis ^ (millis >>> 32));
hash += getType().hashCode();
return hash;
}
}