org.deegree.crs.components
Class Unit

java.lang.Object
  org.deegree.crs.Identifiable
      org.deegree.crs.components.Unit

All Implemented Interfaces:

java.io.Serializable

public final class Unit
extends Identifiable
implements java.io.Serializable

The Unit class defines a mechanism to convert between different measurements units, such as british_yard and meter.

Version:

$Revision: 22735 $, $Date: 2010-02-24 15:46:50 +0100 (Mi, 24 Feb 2010) $

Author:

Rutger Bezema, last edited by: $Author: apoth $

See Also:

Serialized Form

Field Summary

static Unit	ARC_SEC Unit of angle, which is defined to be 1/3600 of a degree, or PI/(180*3600) Radian.
static Unit	BRITISHYARD British yard; unit of length.
static Unit	DAY Unit of time.
static Unit	DEGREE Unit of angle.
static Unit	METRE Base unit of length.
static Unit	MILLISECOND Unit of time.
static Unit	RADIAN Unit of angle.
static Unit	SECOND Base unit of time.
static Unit	USFOOT US foot; unit of length, with base unit of 0.304 meter.

Constructor Summary

Unit(java.lang.String symbol, java.lang.String name)
Unit constructor.

Unit(java.lang.String symbol, java.lang.String name, double scale, Unit baseType)
Unit constructor, which uses the name as the id.

Unit(java.lang.String symbol, java.lang.String name, java.lang.String id)
Unit constructor.

Unit(java.lang.String symbol, java.lang.String name, java.lang.String id, double scale, Unit baseType)
Unit constructor.

Method Summary

boolean	canConvert(Unit other) Check if amount of the specified unit can be converted into amount of this unit.
double	convert(double value, Unit targetUnit) Convert a value in this unit to the given unit if possible.
static Unit	createUnitFromString(java.lang.String unit) Will create a unit from the given String.
boolean	equals(java.lang.Object object) Compare this unit symbol with the specified object for equality.
double	getScale()
java.lang.String	getSymbol()
int	hashCode() Implementation as proposed by Joshua Block in Effective Java (Addison-Wesley 2001), which supplies an even distribution and is relatively fast.
boolean	isBaseType()
double	toBaseUnits(double value) Convert a value in this unit to the base unit, e.g. degree->radians
java.lang.String	toString()

Methods inherited from class org.deegree.crs.Identifiable

checkForNullObject, checkForNullObject, checkForNullObject, getAreaOfUse, getAreaOfUseBBox, getAreasOfUse, getDescription, getDescriptions, getIdAndName, getIdentifier, getIdentifiers, getName, getNames, getVersion, getVersions, hasID

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

RADIAN

public static final Unit RADIAN

Unit of angle.

DEGREE

public static final Unit DEGREE

Unit of angle.

ARC_SEC

public static final Unit ARC_SEC

Unit of angle, which is defined to be 1/3600 of a degree, or PI/(180*3600) Radian.

METRE

public static final Unit METRE

Base unit of length.

BRITISHYARD

public static final Unit BRITISHYARD

British yard; unit of length.

USFOOT

public static final Unit USFOOT

US foot; unit of length, with base unit of 0.304 meter.

SECOND

public static final Unit SECOND

Base unit of time.

MILLISECOND

public static final Unit MILLISECOND

Unit of time.

DAY

public static final Unit DAY

Unit of time.

Constructor Detail

Unit

public Unit(java.lang.String symbol,
            java.lang.String name,
            java.lang.String id)

Unit constructor.

Parameters:

symbol -

name - of the unit, e.g. metre

id - of the unit

Unit

public Unit(java.lang.String symbol,
            java.lang.String name)

Unit constructor.

Parameters:

symbol -

name - of the unit, e.g. metre

Unit

public Unit(java.lang.String symbol,
            java.lang.String name,
            double scale,
            Unit baseType)

Unit constructor, which uses the name as the id.

Parameters:

symbol - of the units, e.g. 'm'

name - human readable name, e.g. metre

scale - to convert to the base type.

baseType - the baseType

Unit

public Unit(java.lang.String symbol,
            java.lang.String name,
            java.lang.String id,
            double scale,
            Unit baseType)

Unit constructor.

Parameters:

symbol - of the units, e.g. 'm'

name - human readable name, e.g. metre

id - of the unit.

scale - to convert to the base type.

baseType - the baseType

Method Detail

createUnitFromString

public static Unit createUnitFromString(java.lang.String unit)

Will create a unit from the given String. If no appropriate unit was found null will be returned.

Parameters:

unit - to convert to an actual unit.

Returns:

a unit or null

canConvert

public boolean canConvert(Unit other)

Check if amount of the specified unit can be converted into amount of this unit.

Parameters:

other -

Returns:

true if this unit can be converted into the other unit

convert

public final double convert(double value,
                            Unit targetUnit)

Convert a value in this unit to the given unit if possible.

Parameters:

value - to be converted

targetUnit - to convert to

Returns:

the converted value or the same value if this unit equals given unit.

Throws:

java.lang.IllegalArgumentException - if no conversion can be applied.

toBaseUnits

public final double toBaseUnits(double value)

Convert a value in this unit to the base unit, e.g. degree->radians

Parameters:

value - to be converted

Returns:

the converted value or the same value if this unit is a base unit.

toString

public java.lang.String toString()

Overrides:

toString in class Identifiable

Returns:

the symbol of this unit.

equals

public boolean equals(java.lang.Object object)

Compare this unit symbol with the specified object for equality. Only symbols are compared; other parameters are ignored.

Overrides:

equals in class Identifiable

hashCode

public int hashCode()

Implementation as proposed by Joshua Block in Effective Java (Addison-Wesley 2001), which supplies an even distribution and is relatively fast. It is created from field f as follows:

• boolean -- code = (f ? 0 : 1)
• byte, char, short, int -- code = (int)f
• long -- code = (int)(f ^ (f >>>32))
• float -- code = Float.floatToIntBits(f);
• double -- long l = Double.doubleToLongBits(f); code = (int)(l ^ (l >>> 32))
• all Objects, (where equals( ) calls equals( ) for this field) -- code = f.hashCode( )
• Array -- Apply above rules to each element

Combining the hash code(s) computed above: result = 37 * result + code;

Overrides:

hashCode in class java.lang.Object

Returns:

(int) ( result >>> 32 ) ^ (int) result;

See Also:

Object.hashCode()

getScale

public final double getScale()

Returns:

the scale to convert to the base unit.

isBaseType

public final boolean isBaseType()

Returns:

true if this is a base type

getSymbol

public java.lang.String getSymbol()

Returns:

symbol (short string) for a Unit