Package org.geotools.referencing.datum

Class DefaultPrimeMeridian

Object

Formattable

AbstractIdentifiedObject

DefaultPrimeMeridian

All Implemented Interfaces:

Serializable, PrimeMeridian, IdentifiedObject

public class DefaultPrimeMeridian
extends AbstractIdentifiedObject
implements PrimeMeridian

A prime meridian defines the origin from which longitude values are determined. The name initial value is "Greenwich", and that value shall be used when the greenwich longitude value is zero.

Since:

2.1

Author:

Martin Desruisseaux (IRD)

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
static DefaultPrimeMeridian	GREENWICH	The Greenwich meridian, with angular measurements in decimal degrees.

Fields inherited from class AbstractIdentifiedObject

EMPTY_ALIAS_ARRAY, EMPTY_IDENTIFIER_ARRAY, IDENTIFIER_COMPARATOR, NAME_COMPARATOR, REMARKS_COMPARATOR

Fields inherited from class Formattable

SINGLE_LINE

Fields inherited from interface IdentifiedObject

ALIAS_KEY, IDENTIFIERS_KEY, NAME_KEY, REMARKS_KEY

Constructor Summary

Constructors

Constructor	Description
DefaultPrimeMeridian(String name, double greenwichLongitude)	Constructs a prime meridian from a name.
DefaultPrimeMeridian(String name, double greenwichLongitude, Unit<Angle> angularUnit)	Constructs a prime meridian from a name.
DefaultPrimeMeridian(Map<String,?> properties, double greenwichLongitude, Unit<Angle> angularUnit)	Constructs a prime meridian from a set of properties.
DefaultPrimeMeridian(PrimeMeridian meridian)	Constructs a new prime meridian with the same values than the specified one.

Method Summary

Modifier and Type	Method	Description
boolean	equals(AbstractIdentifiedObject object, boolean compareMetadata)	Compare this prime meridian with the specified object for equality.
protected String	formatWKT(Formatter formatter)	Format the inner part of a Well Known Text (WKT) element.
Unit<Angle>	getAngularUnit()	Returns the angular unit of the Greenwich longitude.
double	getGreenwichLongitude()	Longitude of the prime meridian measured from the Greenwich meridian, positive eastward.
double	getGreenwichLongitude(Unit<Angle> targetUnit)	Returns the longitude value relative to the Greenwich Meridian, expressed in the specified units.
int	hashCode()	Returns a hash value for this prime meridian.

Methods inherited from class AbstractIdentifiedObject

asSet, ensureAngularUnit, ensureLinearUnit, ensureNonNull, ensureNonNull, ensureTimeUnit, equals, equals, equals, equals, getAlias, getIdentifier, getIdentifier, getIdentifiers, getName, getName, getName, getProperties, getProperties, getRemarks, nameMatches, nameMatches, nameMatches

Methods inherited from class Formattable

cleanupThreadLocals, toString, toWKT, toWKT, toWKT, toWKT

Methods inherited from class Object

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

Methods inherited from interface IdentifiedObject

getAlias, getIdentifiers, getName, getRemarks, toWKT

Field Detail

GREENWICH

public static final DefaultPrimeMeridian GREENWICH

The Greenwich meridian, with angular measurements in decimal degrees.

Constructor Detail

DefaultPrimeMeridian

public DefaultPrimeMeridian(PrimeMeridian meridian)

Constructs a new prime meridian with the same values than the specified one. This copy constructor provides a way to wrap an arbitrary implementation into a Geotools one or a user-defined one (as a subclass), usually in order to leverage some implementation-specific API. This constructor performs a shallow copy, i.e. the properties are not cloned.

Parameters:

meridian - The prime meridian to copy.

Since:

2.2

DefaultPrimeMeridian

public DefaultPrimeMeridian(String name,
                            double greenwichLongitude)

Constructs a prime meridian from a name. The greenwichLongitude value is assumed in decimal degrees.

Parameters:

name - The datum name.

greenwichLongitude - The longitude value relative to the Greenwich Meridian.

DefaultPrimeMeridian

public DefaultPrimeMeridian(String name,
                            double greenwichLongitude,
                            Unit<Angle> angularUnit)

Constructs a prime meridian from a name.

Parameters:

name - The datum name.

greenwichLongitude - The longitude value relative to the Greenwich Meridian.

angularUnit - The angular unit of the longitude.

DefaultPrimeMeridian

public DefaultPrimeMeridian(Map<String,?> properties,
                            double greenwichLongitude,
                            Unit<Angle> angularUnit)

Constructs a prime meridian from a set of properties. The properties map is given unchanged to the super-class constructor.

Parameters:

properties - Set of properties. Should contains at least "name".

greenwichLongitude - The longitude value relative to the Greenwich Meridian.

angularUnit - The angular unit of the longitude.

Method Detail

getGreenwichLongitude

public double getGreenwichLongitude()

Longitude of the prime meridian measured from the Greenwich meridian, positive eastward. The greenwichLongitude initial value is zero, and that value shall be used when the meridian name value is "Greenwich".

Specified by:

getGreenwichLongitude in interface PrimeMeridian

Returns:

The prime meridian Greenwich longitude, in angular unit.

getGreenwichLongitude

public double getGreenwichLongitude(Unit<Angle> targetUnit)

Returns the longitude value relative to the Greenwich Meridian, expressed in the specified units. This convenience method makes it easier to obtain longitude in decimal degrees (getGreenwichLongitude(NonSI.DEGREE_ANGLE)), regardless of the underlying angular units of this prime meridian.

Parameters:

targetUnit - The unit in which to express longitude.

Returns:

The Greenwich longitude in the given units.

getAngularUnit

public Unit<Angle> getAngularUnit()

Returns the angular unit of the Greenwich longitude.

Specified by:

getAngularUnit in interface PrimeMeridian

Returns:

The angular unit of greenwich longitude.

equals

public boolean equals(AbstractIdentifiedObject object,
                      boolean compareMetadata)

Compare this prime meridian with the specified object for equality.

Overrides:

equals in class AbstractIdentifiedObject

Parameters:

object - The object to compare to this.

compareMetadata - true for performing a strict comparaison, or false for comparing only properties relevant to transformations.

Returns:

true if both objects are equal.

hashCode

public int hashCode()

Returns a hash value for this prime meridian. Name, remarks and the like are not taken in account. In other words, two prime meridians will return the same hash value if they are equal in the sense of equals(AbstractIdentifiedObject, false).

Overrides:

hashCode in class AbstractIdentifiedObject

Returns:

The hash code value. This value doesn't need to be the same in past or future versions of this class.

formatWKT

protected String formatWKT(Formatter formatter)

Format the inner part of a Well Known Text (WKT) element.

Overrides:

formatWKT in class Formattable

Parameters:

formatter - The formatter to use.

Returns:

The WKT element name, which is "PRIMEM"

See Also:

Formattable.toWKT(), Formattable.toString()