org.joda.time.field
Class DividedDateTimeField

java.lang.Object
  extended byorg.joda.time.DateTimeField
      extended byorg.joda.time.field.BaseDateTimeField
          extended byorg.joda.time.field.DecoratedDateTimeField
              extended byorg.joda.time.field.DividedDateTimeField

public class DividedDateTimeField
extends DecoratedDateTimeField

Divides a DateTimeField such that the retrieved values are reduced by a fixed divisor. The field's unit duration is scaled accordingly, but the range duration is unchanged.

DividedDateTimeField is thread-safe and immutable.

Since:
1.0
Author:
Stephen Colebourne, Brian S O'Neill
See Also:
RemainderDateTimeField

Constructor Summary
DividedDateTimeField(DateTimeField field, DateTimeFieldType type, int divisor)
          Constructor.
DividedDateTimeField(RemainderDateTimeField remainderField, DateTimeFieldType type)
          Construct a DividedDateTimeField that compliments the given RemainderDateTimeField.
 
Method Summary
 long add(long instant, int amount)
          Add the specified amount of scaled units to the specified time instant.
 long add(long instant, long amount)
          Add the specified amount of scaled units to the specified time instant.
 long addWrapField(long instant, int amount)
          Add to the scaled component of the specified time instant, wrapping around within that component if necessary.
 int get(long instant)
          Get the amount of scaled units from the specified time instant.
 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.
 int getDivisor()
          Returns the divisor applied, in the field's units.
 DurationField getDurationField()
          Returns a scaled version of the wrapped field's unit duration field.
 int getMaximumValue()
          Get the maximum value for the field.
 int getMinimumValue()
          Get the minimum value for the field.
 long remainder(long instant)
          Returns the fractional duration milliseconds of this field.
 long roundFloor(long instant)
          Round to the lowest whole unit of this field.
 long set(long instant, int value)
          Set the specified amount of scaled units to the specified time instant.
 
Methods inherited from class org.joda.time.field.DecoratedDateTimeField
getRangeDurationField, getWrappedField, isLenient
 
Methods inherited from class org.joda.time.field.BaseDateTimeField
add, addWrapField, addWrapPartial, getAsShortText, getAsShortText, getAsShortText, getAsShortText, getAsShortText, getAsText, getAsText, getAsText, getAsText, getAsText, getLeapAmount, getLeapDurationField, getMaximumShortTextLength, getMaximumTextLength, getMaximumValue, getMaximumValue, getMaximumValue, getMinimumValue, getMinimumValue, getMinimumValue, getName, getType, isLeap, isSupported, roundCeiling, roundHalfCeiling, roundHalfEven, roundHalfFloor, set, set, set, set, toString
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

DividedDateTimeField

public DividedDateTimeField(DateTimeField field,
                            DateTimeFieldType type,
                            int divisor)
Constructor.

Parameters:
field - the field to wrap, like "year()".
type - the field type this field will actually use
divisor - divisor, such as 100 years in a century
Throws:
IllegalArgumentException - if divisor is less than two

DividedDateTimeField

public DividedDateTimeField(RemainderDateTimeField remainderField,
                            DateTimeFieldType type)
Construct a DividedDateTimeField that compliments the given RemainderDateTimeField.

Parameters:
remainderField - complimentary remainder field, like "yearOfCentury()".
type - the field type this field will actually use
Method Detail

get

public int get(long instant)
Get the amount of scaled units from the specified time instant.

Overrides:
get in class DecoratedDateTimeField
Parameters:
instant - the time instant in millis to query.
Returns:
the amount of scaled units extracted from the input.

add

public long add(long instant,
                int amount)
Add the specified amount of scaled units to the specified time instant. The amount added may be negative.

Overrides:
add in class BaseDateTimeField
Parameters:
instant - the time instant in millis to update.
amount - the amount of scaled units to add (can be negative).
Returns:
the updated time instant.

add

public long add(long instant,
                long amount)
Add the specified amount of scaled units to the specified time instant. The amount added may be negative.

Overrides:
add in class BaseDateTimeField
Parameters:
instant - the time instant in millis to update.
amount - the amount of scaled units to add (can be negative).
Returns:
the updated time instant.
See Also:
BaseDateTimeField.add(long,int)

addWrapField

public long addWrapField(long instant,
                         int amount)
Add to the scaled component of the specified time instant, wrapping around within that component if necessary.

Overrides:
addWrapField in class BaseDateTimeField
Parameters:
instant - the time instant in millis to update.
amount - the amount of scaled units to add (can be negative).
Returns:
the updated time instant.

getDifference

public int getDifference(long minuendInstant,
                         long subtrahendInstant)
Description copied from class: BaseDateTimeField
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 class BaseDateTimeField
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)
Description copied from class: BaseDateTimeField
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 class BaseDateTimeField
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

set

public long set(long instant,
                int value)
Set the specified amount of scaled units to the specified time instant.

Overrides:
set in class DecoratedDateTimeField
Parameters:
instant - the time instant in millis to update.
value - value of scaled units to set.
Returns:
the updated time instant.
Throws:
IllegalArgumentException - if value is too large or too small.

getDurationField

public DurationField getDurationField()
Returns a scaled version of the wrapped field's unit duration field.

Overrides:
getDurationField in class DecoratedDateTimeField

getMinimumValue

public int getMinimumValue()
Get the minimum value for the field.

Overrides:
getMinimumValue in class DecoratedDateTimeField
Returns:
the minimum value

getMaximumValue

public int getMaximumValue()
Get the maximum value for the field.

Overrides:
getMaximumValue in class DecoratedDateTimeField
Returns:
the maximum value

roundFloor

public long roundFloor(long instant)
Description copied from class: BaseDateTimeField
Round to the lowest whole unit of this field. After rounding, the value of this field and all fields of a higher magnitude are retained. The fractional millis that cannot be expressed in whole increments of this field are set to minimum.

For example, a datetime of 2002-11-02T23:34:56.789, rounded to the lowest whole hour is 2002-11-02T23:00:00.000.

Overrides:
roundFloor in class DecoratedDateTimeField

remainder

public long remainder(long instant)
Description copied from class: BaseDateTimeField
Returns the fractional duration milliseconds of this field. In other words, calling remainder returns the duration that roundFloor would subtract.

For example, on a datetime of 2002-11-02T23:34:56.789, the remainder by hour is 34 minutes and 56.789 seconds.

The default implementation computes instant - roundFloor(instant). Subclasses are encouraged to provide a more efficient implementation.

Overrides:
remainder in class BaseDateTimeField
Parameters:
instant - the milliseconds from 1970-01-01T00:00:00Z to get the remainder
Returns:
remainder duration, in milliseconds

getDivisor

public int getDivisor()
Returns the divisor applied, in the field's units.

Returns:
the divisor


Copyright © 2002-2008 Joda.org. All Rights Reserved.