/*
* Copyright 2001-2010 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;
import org.joda.convert.FromString;
import org.joda.convert.ToString;
import org.joda.time.base.BaseSingleFieldPeriod;
import org.joda.time.field.FieldUtils;
import org.joda.time.format.ISOPeriodFormat;
import org.joda.time.format.PeriodFormatter;
/**
* An immutable time period representing a number of hours.
* <p>
* <code>Hours</code> is an immutable period that can only store hours.
* It does not store years, months or minutes for example. As such it is a
* type-safe way of representing a number of hours in an application.
* <p>
* The number of hours is set in the constructor, and may be queried using
* <code>getHours()</code>. Basic mathematical operations are provided -
* <code>plus()</code>, <code>minus()</code>, <code>multipliedBy()</code> and
* <code>dividedBy()</code>.
* <p>
* <code>Hours</code> is thread-safe and immutable.
*
* @author Stephen Colebourne
* @since 1.4
*/
public final class Hours extends BaseSingleFieldPeriod {
/** Constant representing zero hours. */
public static final Hours ZERO = new Hours(0);
/** Constant representing one hour. */
public static final Hours ONE = new Hours(1);
/** Constant representing two hours. */
public static final Hours TWO = new Hours(2);
/** Constant representing three hours. */
public static final Hours THREE = new Hours(3);
/** Constant representing four hours. */
public static final Hours FOUR = new Hours(4);
/** Constant representing five hours. */
public static final Hours FIVE = new Hours(5);
/** Constant representing six hours. */
public static final Hours SIX = new Hours(6);
/** Constant representing seven hours. */
public static final Hours SEVEN = new Hours(7);
/** Constant representing eight hours. */
public static final Hours EIGHT = new Hours(8);
/** Constant representing the maximum number of hours that can be stored in this object. */
public static final Hours MAX_VALUE = new Hours(Integer.MAX_VALUE);
/** Constant representing the minimum number of hours that can be stored in this object. */
public static final Hours MIN_VALUE = new Hours(Integer.MIN_VALUE);
/** The paser to use for this class. */
private static final PeriodFormatter PARSER = ISOPeriodFormat.standard().withParseType(PeriodType.hours());
/** Serialization version. */
private static final long serialVersionUID = 87525275727380864L;
//-----------------------------------------------------------------------
/**
* Obtains an instance of <code>Hours</code> that may be cached.
* <code>Hours</code> is immutable, so instances can be cached and shared.
* This factory method provides access to shared instances.
*
* @param hours the number of hours to obtain an instance for
* @return the instance of Hours
*/
public static Hours hours(int hours) {
switch (hours) {
case 0:
return ZERO;
case 1:
return ONE;
case 2:
return TWO;
case 3:
return THREE;
case 4:
return FOUR;
case 5:
return FIVE;
case 6:
return SIX;
case 7:
return SEVEN;
case 8:
return EIGHT;
case Integer.MAX_VALUE:
return MAX_VALUE;
case Integer.MIN_VALUE:
return MIN_VALUE;
default:
return new Hours(hours);
}
}
//-----------------------------------------------------------------------
/**
* Creates a <code>Hours</code> representing the number of whole hours
* between the two specified datetimes.
*
* @param start the start instant, must not be null
* @param end the end instant, must not be null
* @return the period in hours
* @throws IllegalArgumentException if the instants are null or invalid
*/
public static Hours hoursBetween(ReadableInstant start, ReadableInstant end) {
int amount = BaseSingleFieldPeriod.between(start, end, DurationFieldType.hours());
return Hours.hours(amount);
}
/**
* Creates a <code>Hours</code> representing the number of whole hours
* between the two specified partial datetimes.
* <p>
* The two partials must contain the same fields, for example you can specify
* two <code>LocalTime</code> objects.
*
* @param start the start partial date, must not be null
* @param end the end partial date, must not be null
* @return the period in hours
* @throws IllegalArgumentException if the partials are null or invalid
*/
public static Hours hoursBetween(ReadablePartial start, ReadablePartial end) {
if (start instanceof LocalTime && end instanceof LocalTime) {
Chronology chrono = DateTimeUtils.getChronology(start.getChronology());
int hours = chrono.hours().getDifference(
((LocalTime) end).getLocalMillis(), ((LocalTime) start).getLocalMillis());
return Hours.hours(hours);
}
int amount = BaseSingleFieldPeriod.between(start, end, ZERO);
return Hours.hours(amount);
}
/**
* Creates a <code>Hours</code> representing the number of whole hours
* in the specified interval.
*
* @param interval the interval to extract hours from, null returns zero
* @return the period in hours
* @throws IllegalArgumentException if the partials are null or invalid
*/
public static Hours hoursIn(ReadableInterval interval) {
if (interval == null) {
return Hours.ZERO;
}
int amount = BaseSingleFieldPeriod.between(interval.getStart(), interval.getEnd(), DurationFieldType.hours());
return Hours.hours(amount);
}
/**
* Creates a new <code>Hours</code> representing the number of complete
* standard length hours in the specified period.
* <p>
* This factory method converts all fields from the period to hours using standardised
* durations for each field. Only those fields which have a precise duration in
* the ISO UTC chronology can be converted.
* <ul>
* <li>One week consists of 7 days.
* <li>One day consists of 24 hours.
* <li>One hour consists of 60 minutes.
* <li>One minute consists of 60 seconds.
* <li>One second consists of 1000 milliseconds.
* </ul>
* Months and Years are imprecise and periods containing these values cannot be converted.
*
* @param period the period to get the number of hours from, null returns zero
* @return the period in hours
* @throws IllegalArgumentException if the period contains imprecise duration values
*/
public static Hours standardHoursIn(ReadablePeriod period) {
int amount = BaseSingleFieldPeriod.standardPeriodIn(period, DateTimeConstants.MILLIS_PER_HOUR);
return Hours.hours(amount);
}
/**
* Creates a new <code>Hours</code> by parsing a string in the ISO8601 format 'PTnH'.
* <p>
* The parse will accept the full ISO syntax of PnYnMnWnDTnHnMnS however only the
* hours component may be non-zero. If any other component is non-zero, an exception
* will be thrown.
*
* @param periodStr the period string, null returns zero
* @return the period in hours
* @throws IllegalArgumentException if the string format is invalid
*/
@FromString
public static Hours parseHours(String periodStr) {
if (periodStr == null) {
return Hours.ZERO;
}
Period p = PARSER.parsePeriod(periodStr);
return Hours.hours(p.getHours());
}
//-----------------------------------------------------------------------
/**
* Creates a new instance representing a number of hours.
* You should consider using the factory method {@link #hours(int)}
* instead of the constructor.
*
* @param hours the number of hours to represent
*/
private Hours(int hours) {
super(hours);
}
/**
* Resolves singletons.
*
* @return the singleton instance
*/
private Object readResolve() {
return Hours.hours(getValue());
}
//-----------------------------------------------------------------------
/**
* Gets the duration field type, which is <code>hours</code>.
*
* @return the period type
*/
public DurationFieldType getFieldType() {
return DurationFieldType.hours();
}
/**
* Gets the period type, which is <code>hours</code>.
*
* @return the period type
*/
public PeriodType getPeriodType() {
return PeriodType.hours();
}
//-----------------------------------------------------------------------
/**
* Converts this period in hours to a period in weeks assuming a
* 7 day week and 24 hour day.
* <p>
* This method allows you to convert between different types of period.
* However to achieve this it makes the assumption that all weeks are 7 days
* long and all days are 24 hours long.
* This is not true when daylight savings time is considered, and may also
* not be true for some unusual chronologies. However, it is included as it
* is a useful operation for many applications and business rules.
*
* @return a period representing the number of whole weeks for this number of hours
*/
public Weeks toStandardWeeks() {
return Weeks.weeks(getValue() / DateTimeConstants.HOURS_PER_WEEK);
}
/**
* Converts this period in hours to a period in days assuming a
* 24 hour day.
* <p>
* This method allows you to convert between different types of period.
* However to achieve this it makes the assumption that all days are 24 hours long.
* This is not true when daylight savings time is considered, and may also
* not be true for some unusual chronologies. However, it is included as it
* is a useful operation for many applications and business rules.
*
* @return a period representing the number of whole days for this number of hours
*/
public Days toStandardDays() {
return Days.days(getValue() / DateTimeConstants.HOURS_PER_DAY);
}
/**
* Converts this period in hours to a period in minutes assuming a
* 60 minute hour.
* <p>
* This method allows you to convert between different types of period.
* However to achieve this it makes the assumption that all hours are 60 minutes long.
* This may not be true for some unusual chronologies. However, it is included
* as it is a useful operation for many applications and business rules.
*
* @return a period representing the number of minutes for this number of hours
* @throws ArithmeticException if the number of minutes is too large to be represented
*/
public Minutes toStandardMinutes() {
return Minutes.minutes(FieldUtils.safeMultiply(getValue(), DateTimeConstants.MINUTES_PER_HOUR));
}
/**
* Converts this period in hours to a period in seconds assuming a
* 60 minute hour and 60 second minute.
* <p>
* This method allows you to convert between different types of period.
* However to achieve this it makes the assumption that all hours are
* 60 minutes long and all minutes are 60 seconds long.
* This may not be true for some unusual chronologies. However, it is included
* as it is a useful operation for many applications and business rules.
*
* @return a period representing the number of seconds for this number of hours
* @throws ArithmeticException if the number of seconds is too large to be represented
*/
public Seconds toStandardSeconds() {
return Seconds.seconds(FieldUtils.safeMultiply(getValue(), DateTimeConstants.SECONDS_PER_HOUR));
}
//-----------------------------------------------------------------------
/**
* Converts this period in hours to a duration in milliseconds assuming a
* 60 minute hour and 60 second minute.
* <p>
* This method allows you to convert from a period to a duration.
* However to achieve this it makes the assumption that all hours are
* 60 minutes and all minutes are 60 seconds. This might not be true for an
* unusual chronology, for example one that takes leap seconds into account.
* However, the method is included as it is a useful operation for many
* applications and business rules.
*
* @return a duration equivalent to this number of hours
*/
public Duration toStandardDuration() {
long hours = getValue(); // assign to a long
return new Duration(hours * DateTimeConstants.MILLIS_PER_HOUR);
}
//-----------------------------------------------------------------------
/**
* Gets the number of hours that this period represents.
*
* @return the number of hours in the period
*/
public int getHours() {
return getValue();
}
//-----------------------------------------------------------------------
/**
* Returns a new instance with the specified number of hours added.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param hours the amount of hours to add, may be negative
* @return the new period plus the specified number of hours
* @throws ArithmeticException if the result overflows an int
*/
public Hours plus(int hours) {
if (hours == 0) {
return this;
}
return Hours.hours(FieldUtils.safeAdd(getValue(), hours));
}
/**
* Returns a new instance with the specified number of hours added.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param hours the amount of hours to add, may be negative, null means zero
* @return the new period plus the specified number of hours
* @throws ArithmeticException if the result overflows an int
*/
public Hours plus(Hours hours) {
if (hours == null) {
return this;
}
return plus(hours.getValue());
}
//-----------------------------------------------------------------------
/**
* Returns a new instance with the specified number of hours taken away.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param hours the amount of hours to take away, may be negative
* @return the new period minus the specified number of hours
* @throws ArithmeticException if the result overflows an int
*/
public Hours minus(int hours) {
return plus(FieldUtils.safeNegate(hours));
}
/**
* Returns a new instance with the specified number of hours taken away.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param hours the amount of hours to take away, may be negative, null means zero
* @return the new period minus the specified number of hours
* @throws ArithmeticException if the result overflows an int
*/
public Hours minus(Hours hours) {
if (hours == null) {
return this;
}
return minus(hours.getValue());
}
//-----------------------------------------------------------------------
/**
* Returns a new instance with the hours multiplied by the specified scalar.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param scalar the amount to multiply by, may be negative
* @return the new period multiplied by the specified scalar
* @throws ArithmeticException if the result overflows an int
*/
public Hours multipliedBy(int scalar) {
return Hours.hours(FieldUtils.safeMultiply(getValue(), scalar));
}
/**
* Returns a new instance with the hours divided by the specified divisor.
* The calculation uses integer division, thus 3 divided by 2 is 1.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param divisor the amount to divide by, may be negative
* @return the new period divided by the specified divisor
* @throws ArithmeticException if the divisor is zero
*/
public Hours dividedBy(int divisor) {
if (divisor == 1) {
return this;
}
return Hours.hours(getValue() / divisor);
}
//-----------------------------------------------------------------------
/**
* Returns a new instance with the hours value negated.
*
* @return the new period with a negated value
* @throws ArithmeticException if the result overflows an int
*/
public Hours negated() {
return Hours.hours(FieldUtils.safeNegate(getValue()));
}
//-----------------------------------------------------------------------
/**
* Is this hours instance greater than the specified number of hours.
*
* @param other the other period, null means zero
* @return true if this hours instance is greater than the specified one
*/
public boolean isGreaterThan(Hours other) {
if (other == null) {
return getValue() > 0;
}
return getValue() > other.getValue();
}
/**
* Is this hours instance less than the specified number of hours.
*
* @param other the other period, null means zero
* @return true if this hours instance is less than the specified one
*/
public boolean isLessThan(Hours other) {
if (other == null) {
return getValue() < 0;
}
return getValue() < other.getValue();
}
//-----------------------------------------------------------------------
/**
* Gets this instance as a String in the ISO8601 duration format.
* <p>
* For example, "PT4H" represents 4 hours.
*
* @return the value as an ISO8601 string
*/
@ToString
public String toString() {
return "PT" + String.valueOf(getValue()) + "H";
}
}