org.joda.time.field

Class ScaledDurationField

Implemented Interfaces:
Comparable, Serializable

public class ScaledDurationField
extends DecoratedDurationField

Scales a DurationField such that it's unit millis becomes larger in magnitude.

ScaledDurationField is thread-safe and immutable.

Author:
Brian S O'Neill
Since:
1.0
See Also:
PreciseDurationField

Constructor Summary

ScaledDurationField(DurationField field, DurationFieldType type, int scalar)
Constructor

Method Summary

long
add(long instant, int value)
Adds a duration value (which may be negative) to the instant.
long
add(long instant, long value)
Adds a duration value (which may be negative) to the instant.
boolean
equals(Object obj)
Compares this duration field to another.
int
getDifference(long minuendInstant, long subtrahendInstant)
Computes the difference between two instants, as measured in the units of this field.
long
getDifferenceAsLong(long minuendInstant, long subtrahendInstant)
Computes the difference between two instants, as measured in the units of this field.
long
getMillis(int value)
Get the millisecond duration of this field from its value, which is approximate if this field is imprecise.
long
getMillis(int value, long instant)
Get the millisecond duration of this field from its value relative to an instant.
long
getMillis(long value)
Get the millisecond duration of this field from its value, which is approximate if this field is imprecise.
long
getMillis(long value, long instant)
Get the millisecond duration of this field from its value relative to an instant.
int
getScalar()
Returns the scalar applied, in the field's units.
long
getUnitMillis()
Returns the amount of milliseconds per unit value of this field.
int
getValue(long duration)
Get the value of this field from the milliseconds, which is approximate if this field is imprecise.
int
getValue(long duration, long instant)
Get the value of this field from the milliseconds relative to an instant.
long
getValueAsLong(long duration)
Get the value of this field from the milliseconds, which is approximate if this field is imprecise.
long
getValueAsLong(long duration, long instant)
Get the value of this field from the milliseconds relative to an instant.
int
hashCode()
Gets a hash code for this instance.

Methods inherited from class org.joda.time.field.DecoratedDurationField

add, add, getDifferenceAsLong, getMillis, getMillis, getUnitMillis, getValueAsLong, getWrappedField, isPrecise

Methods inherited from class org.joda.time.field.BaseDurationField

compareTo, getDifference, getMillis, getMillis, getName, getType, getValue, getValue, getValueAsLong, isSupported, toString

Methods inherited from class org.joda.time.DurationField

add, add, compareTo, getDifference, getDifferenceAsLong, getMillis, getMillis, getMillis, getMillis, getName, getType, getUnitMillis, getValue, getValue, getValueAsLong, getValueAsLong, isPrecise, isSupported, subtract, subtract, toString

Constructor Details

ScaledDurationField

public ScaledDurationField(DurationField field,
                           DurationFieldType type,
                           int scalar)
Constructor
Parameters:
field - the field to wrap, like "year()".
type - the type this field will actually use
scalar - scalar, such as 100 years in a century

Method Details

add

public long add(long instant,
                int value)
Adds a duration value (which may be negative) to the instant.
Overrides:
add in interface DecoratedDurationField
Parameters:
instant - the milliseconds from 1970-01-01T00:00:00Z to add to
value - the value to add, in the units of the field
Returns:
the updated milliseconds

add

public long add(long instant,
                long value)
Adds a duration value (which may be negative) to the instant.
Overrides:
add in interface DecoratedDurationField
Parameters:
instant - the milliseconds from 1970-01-01T00:00:00Z to add to
value - the value to add, in the units of the field
Returns:
the updated milliseconds

equals

public boolean equals(Object obj)
Compares this duration field to another. Two fields are equal if of the same type and duration.
Parameters:
obj - the object to compare to
Returns:
if equal

getDifference

public int getDifference(long minuendInstant,
                         long subtrahendInstant)
Computes the difference between two instants, as measured in the units of this field. Any fractional units are dropped from the result. Calling getDifference reverses the effect of calling add. In the following code:
 long instant = ...
 int v = ...
 int age = getDifference(add(instant, v), instant);
 
The value 'age' is the same as the value 'v'.
Overrides:
getDifference in interface BaseDurationField
Parameters:
minuendInstant - the milliseconds from 1970-01-01T00:00:00Z to subtract from
subtrahendInstant - the milliseconds from 1970-01-01T00:00:00Z to subtract off the minuend
Returns:
the difference in the units of this field

getDifferenceAsLong

public long getDifferenceAsLong(long minuendInstant,
                                long subtrahendInstant)
Computes the difference between two instants, as measured in the units of this field. Any fractional units are dropped from the result. Calling getDifference reverses the effect of calling add. In the following code:
 long instant = ...
 long v = ...
 long age = getDifferenceAsLong(add(instant, v), instant);
 
The value 'age' is the same as the value 'v'.
Overrides:
getDifferenceAsLong in interface DecoratedDurationField
Parameters:
minuendInstant - the milliseconds from 1970-01-01T00:00:00Z to subtract from
subtrahendInstant - the milliseconds from 1970-01-01T00:00:00Z to subtract off the minuend
Returns:
the difference in the units of this field

getMillis

public long getMillis(int value)
Get the millisecond duration of this field from its value, which is approximate if this field is imprecise.
Overrides:
getMillis in interface BaseDurationField
Parameters:
value - the value of the field, which may be negative
Returns:
the milliseconds that the field represents, which may be negative

getMillis

public long getMillis(int value,
                      long instant)
Get the millisecond duration of this field from its value relative to an instant. For precise fields this method produces the same result as for the single argument getMillis method.

If the value is positive, then the instant is treated as a "start instant". If negative, the instant is treated as an "end instant".

Overrides:
getMillis in interface DecoratedDurationField
Parameters:
value - the value of the field, which may be negative
instant - the instant to calculate relative to
Returns:
the millisecond duration that the field represents, which may be negative

getMillis

public long getMillis(long value)
Get the millisecond duration of this field from its value, which is approximate if this field is imprecise.
Overrides:
getMillis in interface BaseDurationField
Parameters:
value - the value of the field, which may be negative
Returns:
the milliseconds that the field represents, which may be negative

getMillis

public long getMillis(long value,
                      long instant)
Get the millisecond duration of this field from its value relative to an instant. For precise fields this method produces the same result as for the single argument getMillis method.

If the value is positive, then the instant is treated as a "start instant". If negative, the instant is treated as an "end instant".

Overrides:
getMillis in interface DecoratedDurationField
Parameters:
value - the value of the field, which may be negative
instant - the instant to calculate relative to
Returns:
the millisecond duration that the field represents, which may be negative

getScalar

public int getScalar()
Returns the scalar applied, in the field's units.
Returns:
the scalar

getUnitMillis

public long getUnitMillis()
Returns the amount of milliseconds per unit value of this field. For example, if this field represents "seconds", then this returns the milliseconds in one second.

For imprecise fields, the unit size is variable, and so this method returns a suitable average value.

Overrides:
getUnitMillis in interface DecoratedDurationField
Returns:
the unit size of this field, in milliseconds

getValue

public int getValue(long duration)
Get the value of this field from the milliseconds, which is approximate if this field is imprecise.
Overrides:
getValue in interface BaseDurationField
Parameters:
duration - the milliseconds to query, which may be negative
Returns:
the value of the field, in the units of the field, which may be negative

getValue

public int getValue(long duration,
                    long instant)
Get the value of this field from the milliseconds relative to an instant.

If the milliseconds is positive, then the instant is treated as a "start instant". If negative, the instant is treated as an "end instant".

The default implementation returns Utils.safeToInt(getAsLong(millisDuration, instant)).

Overrides:
getValue in interface BaseDurationField
Parameters:
duration - the milliseconds to query, which may be negative
instant - the start instant to calculate relative to
Returns:
the value of the field, in the units of the field, which may be negative

getValueAsLong

public long getValueAsLong(long duration)
Get the value of this field from the milliseconds, which is approximate if this field is imprecise.
Overrides:
getValueAsLong in interface BaseDurationField
Parameters:
duration - the milliseconds to query, which may be negative
Returns:
the value of the field, in the units of the field, which may be negative

getValueAsLong

public long getValueAsLong(long duration,
                           long instant)
Get the value of this field from the milliseconds relative to an instant. For precise fields this method produces the same result as for the single argument get method.

If the millisecond duration is positive, then the instant is treated as a "start instant". If negative, the instant is treated as an "end instant".

Overrides:
getValueAsLong in interface DecoratedDurationField
Parameters:
duration - the milliseconds to query, which may be negative
instant - the start instant to calculate relative to
Returns:
the value of the field, in the units of the field, which may be negative

hashCode

public int hashCode()
Gets a hash code for this instance.
Returns:
a suitable hashcode

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