org.openstreetmap.josm.data

Class SystemOfMeasurement

java.lang.Object

org.openstreetmap.josm.data.SystemOfMeasurement

public class SystemOfMeasurement
extends Object

A system of units used to express length and area measurements.

This class also manages one globally set system of measurement stored in the ProjectionPreference

Since:

3406 (creation), 6992 (extraction in this package)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	SystemOfMeasurement.SoMChangeListener Interface to notify listeners of the change of the system of measurement.

Field Summary

Fields

Modifier and Type	Field and Description
static Map<String,SystemOfMeasurement>	ALL_SYSTEMS Known systems of measurement.
String	aName First unit used to format text.
String	areaCustomName Specific optional area unit.
double	areaCustomValue Specific optional area value, in squared meters, between aValue*aValue and bValue*bValue.
double	aValue First value, in meters, used to translate unit according to above formula.
String	bName Second unit used to format text.
double	bValue Second value, in meters, used to translate unit according to above formula.
static SystemOfMeasurement	CHINESE Chinese system.
static SystemOfMeasurement	IMPERIAL Imperial system (British Commonwealth and former British Empire).
static SystemOfMeasurement	METRIC Metric system (international standard).
static SystemOfMeasurement	NAUTICAL_MILE Nautical mile system (navigation, polar exploration).
private static CopyOnWriteArrayList<SystemOfMeasurement.SoMChangeListener>	somChangeListeners

Constructor Summary

Constructors

Constructor and Description
SystemOfMeasurement(double aValue, String aName, double bValue, String bName) System of measurement.
SystemOfMeasurement(double aValue, String aName, double bValue, String bName, double areaCustomValue, String areaCustomName) System of measurement.

Method Summary

Modifier and Type	Method and Description
static void	addSoMChangeListener(SystemOfMeasurement.SoMChangeListener listener) Adds a SoM change listener.
protected static void	fireSoMChanged(String oldSoM, String newSoM)
private static String	formatText(double v, String unit, NumberFormat format)
String	getAreaText(double area) Returns the text describing the given area in this system of measurement.
String	getAreaText(double area, NumberFormat format, double threshold) Returns the text describing the given area in this system of measurement.
String	getDistText(double dist) Returns the text describing the given distance in this system of measurement.
String	getDistText(double dist, NumberFormat format, double threshold) Returns the text describing the given distance in this system of measurement.
static SystemOfMeasurement	getSystemOfMeasurement() Returns the current global system of measurement.
static void	removeSoMChangeListener(SystemOfMeasurement.SoMChangeListener listener) Removes a global SoM change listener.
static void	setSystemOfMeasurement(String somKey) Sets the current global system of measurement.

Methods inherited from class java.lang.Object

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

Field Detail

METRIC

public static final SystemOfMeasurement METRIC

Metric system (international standard).

Since:

3406

CHINESE

public static final SystemOfMeasurement CHINESE

Chinese system.

Since:

3406

IMPERIAL

public static final SystemOfMeasurement IMPERIAL

Imperial system (British Commonwealth and former British Empire).

Since:

3406

NAUTICAL_MILE

public static final SystemOfMeasurement NAUTICAL_MILE

Nautical mile system (navigation, polar exploration).

Since:

5549

ALL_SYSTEMS

public static final Map<String,SystemOfMeasurement> ALL_SYSTEMS

Known systems of measurement.

Since:

3406

somChangeListeners

private static final CopyOnWriteArrayList<SystemOfMeasurement.SoMChangeListener> somChangeListeners

aValue

public final double aValue

First value, in meters, used to translate unit according to above formula.

bValue

public final double bValue

Second value, in meters, used to translate unit according to above formula.

aName

public final String aName

First unit used to format text.

bName

public final String bName

Second unit used to format text.

areaCustomValue

public final double areaCustomValue

Specific optional area value, in squared meters, between aValue*aValue and bValue*bValue. Set to -1 if not used.

Since:

5870

areaCustomName

public final String areaCustomName

Specific optional area unit. Set to null if not used.

Since:

5870

Constructor Detail

SystemOfMeasurement

public SystemOfMeasurement(double aValue,
                           String aName,
                           double bValue,
                           String bName)

System of measurement. Currently covers only length (and area) units. If a quantity x is given in m (x_m) and in unit a (x_a) then it translates as x_a == x_m / aValue

Parameters:

aValue - First value, in meters, used to translate unit according to above formula.

aName - First unit used to format text.

bValue - Second value, in meters, used to translate unit according to above formula.

bName - Second unit used to format text.

SystemOfMeasurement

public SystemOfMeasurement(double aValue,
                           String aName,
                           double bValue,
                           String bName,
                           double areaCustomValue,
                           String areaCustomName)

System of measurement. Currently covers only length (and area) units. If a quantity x is given in m (x_m) and in unit a (x_a) then it translates as x_a == x_m / aValue

Parameters:

aValue - First value, in meters, used to translate unit according to above formula.

aName - First unit used to format text.

bValue - Second value, in meters, used to translate unit according to above formula.

bName - Second unit used to format text.

areaCustomValue - Specific optional area value, in squared meters, between aValue*aValue and bValue*bValue. Set to -1 if not used.

areaCustomName - Specific optional area unit. Set to null if not used.

Since:

5870

Method Detail

removeSoMChangeListener

public static void removeSoMChangeListener(SystemOfMeasurement.SoMChangeListener listener)

Removes a global SoM change listener.

Parameters:

listener - the listener. Ignored if null or already absent

Since:

8554

addSoMChangeListener

public static void addSoMChangeListener(SystemOfMeasurement.SoMChangeListener listener)

Adds a SoM change listener.

Parameters:

listener - the listener. Ignored if null or already registered.

Since:

8554

fireSoMChanged

protected static void fireSoMChanged(String oldSoM,
                                     String newSoM)

getSystemOfMeasurement

public static SystemOfMeasurement getSystemOfMeasurement()

Returns the current global system of measurement.

Returns:

The current system of measurement (metric system by default).

Since:

8554

setSystemOfMeasurement

public static void setSystemOfMeasurement(String somKey)

Sets the current global system of measurement.

Parameters:

somKey - The system of measurement key. Must be defined in ALL_SYSTEMS.

Throws:

IllegalArgumentException - if somKey is not known

Since:

8554

getDistText

public String getDistText(double dist)

Returns the text describing the given distance in this system of measurement.

Parameters:

dist - The distance in metres

Returns:

The text describing the given distance in this system of measurement.

getDistText

public String getDistText(double dist,
                          NumberFormat format,
                          double threshold)

Returns the text describing the given distance in this system of measurement.

Parameters:

dist - The distance in metres

format - A NumberFormat to format the area value

threshold - Values lower than this threshold are displayed as "< [threshold]"

Returns:

The text describing the given distance in this system of measurement.

Since:

6422

getAreaText

public String getAreaText(double area)

Returns the text describing the given area in this system of measurement.

Parameters:

area - The area in square metres

Returns:

The text describing the given area in this system of measurement.

Since:

5560

getAreaText

public String getAreaText(double area,
                          NumberFormat format,
                          double threshold)

Returns the text describing the given area in this system of measurement.

Parameters:

area - The area in square metres

format - A NumberFormat to format the area value

threshold - Values lower than this threshold are displayed as "< [threshold]"

Returns:

The text describing the given area in this system of measurement.

Since:

6422

formatText

private static String formatText(double v,
                                 String unit,
                                 NumberFormat format)