net.sf.basedb.util.units
Class LinearUnitConverter

java.lang.Object
  net.sf.basedb.util.units.LinearUnitConverter

All Implemented Interfaces:

UnitConverter

public class LinearUnitConverter
extends Object
implements UnitConverter

A linear unit converter is a converter implementation were all units can be converted to another unit using a multiplication factor and/or an offset. The formula used in this converter is:

value(ref) = value(specific) * factor + offset

Version:

2.9

Author:

Nicklas

Last modified

$Date$

Field Summary

private double	factor
private double	offset

Constructor Summary

LinearUnitConverter(double factor, double offset)
Create a new unit converter.

LinearUnitConverter(double factor, double offset, double referenceFactor, double referenceOffset)
Create a unit converter that converts between two units that are both related to a third "common" unit by given factors and offsets.

LinearUnitConverter(Unit unit)
Create a new unit converter that converts to/from a given unit.

LinearUnitConverter(Unit specific, Unit reference)
Create a new unit converter that converts to/from given specific and reference unit.

Method Summary

double	convertToReferenceUnit(double specific) value(ref) = value(specific) * factor + offset
double	convertToSpecificUnit(double ref) value(specific) = (value(ref) - offset) / factor

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

factor

private final double factor

offset

private final double offset

Constructor Detail

LinearUnitConverter

public LinearUnitConverter(double factor,
                           double offset)

Create a new unit converter.

Parameters:

factor - The factor to use when converting values

offset - The offset to use when converting values

LinearUnitConverter

public LinearUnitConverter(double factor,
                           double offset,
                           double referenceFactor,
                           double referenceOffset)

Create a unit converter that converts between two units that are both related to a third "common" unit by given factors and offsets. The formula used is: value(ref) * factor(ref) + offset(ref) == value(specific) * factor(specfic) + offset(specific) which is equivalent to :

factor = factor(specific) / factor(ref)
offset = (offset(specific) - offset(ref)) / factor(ref)

Parameters:

factor - The factor of the specific unit

offset - The offset of the specific unit

referenceFactor - The factor of the reference unit

referenceOffset - The offset of the specific unit

LinearUnitConverter

public LinearUnitConverter(Unit unit)

Create a new unit converter that converts to/from a given unit. The reference unit is the unit given by Quantity.getReferenceUnit() for the given specific unit's quantity.

Parameters:

unit - The specific unit

LinearUnitConverter

public LinearUnitConverter(Unit specific,
                           Unit reference)

Create a new unit converter that converts to/from given specific and reference unit.

Parameters:

specific - The specific unit

reference - The reference unit

Method Detail

convertToReferenceUnit

public double convertToReferenceUnit(double specific)

value(ref) = value(specific) * factor + offset

Specified by:

convertToReferenceUnit in interface UnitConverter

Parameters:

specific - The value to convert

Returns:

The converted value

convertToSpecificUnit

public double convertToSpecificUnit(double ref)

value(specific) = (value(ref) - offset) / factor

Specified by:

convertToSpecificUnit in interface UnitConverter

Parameters:

ref - The reference value

Returns:

The converted value