org.geotools.referencing.factory

Class OrderedAxisAuthorityFactory

Object

AbstractFactory

ReferencingFactory

AbstractAuthorityFactory

AuthorityFactoryAdapter

TransformedAuthorityFactory

OrderedAxisAuthorityFactory

All Implemented Interfaces:

Comparator, RegisterableService, Factory, OptionalFactory, AuthorityFactory, CRSAuthorityFactory, CSAuthorityFactory

public class OrderedAxisAuthorityFactory
extends TransformedAuthorityFactory
implements CSAuthorityFactory, CRSAuthorityFactory, Comparator

An authority factory which delegates all the work to an other factory, and reorder the axis in some pre-determined order. This factory is mostly used by application expecting geographic coordinates in (longitude, latitude) order, while most geographic CRS specified in the EPSG database use the opposite axis order.

It is better to avoid this class if you can. This class exists primarily for compatibility with external data or applications that assume (longitude, latitude) axis order no matter what the EPSG database said, for example Shapefiles.

The axis order can be specified at construction time as an array of axis directions. If no such array is explicitly specified, then the default order is East, East-North-East, North-East, North-North-East, North, Up, Geocentric X, Geocentric Y, Geocentric Z, Column, Row, Display right, Display up and Future. This means that, for example, axis with East or West direction will be placed before any axis with North or South direction. Axis directions not specified in the table (for example OTHER) will be ordered last. This is somewhat equivalent to the ordering of NaN values in an array of double.

Notes:

• This class compares only the "absolute" axis directions, so North and South are considered equivalent.
• The default direction order may changes in future Geotools version in order to fit what appears to be the most common usage on the market.
• The actual axis ordering is determined by the compare method implementation. Subclasses may override this method if the want to provide a more sophesticated axis ordering.

For some authority factories, an instance of this class can be obtained by passing a FORCE_LONGITUDE_FIRST_AXIS_ORDER hint to the FactoryFinder.getCRSAuthorityFactory(...) method. Whatever this hint is supported or not is authority dependent. Example:

 Hints                   hints = new Hints(Hints.FORCE_LONGITUDE_FIRST_AXIS_ORDER, Boolean.TRUE);
 CRSAuthorityFactory   factory = FactoryFinder.getCRSAuthorityFactory("EPSG", hints);
 CoordinateReferenceSystem crs = factory.createCoordinateReferenceSystem("EPSG:4326");
 

This class is named ordered axis authority factory instead of something like longitude first axis order because the axis order can be user-supplied. The (longitude, latitude) order just appears to be the default one.

Since:

2.2

Author:

Martin Desruisseaux (IRD)

See Also:

Hints.FORCE_LONGITUDE_FIRST_AXIS_ORDER, Hints.FORCE_STANDARD_AXIS_UNITS

Tutorial:

The axis order issue

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	forceStandardDirections true if this authority factory should also force the axis to their standard direction.
protected boolean	forceStandardUnits true if this authority factory should also force all angular units to decimal degrees and linear units to meters.

Fields inherited from class ReferencingFactory

LOGGER

Fields inherited from class AbstractFactory

hints, MAXIMUM_PRIORITY, MINIMUM_PRIORITY, NORMAL_PRIORITY, priority

Constructor Summary

Constructors

Constructor and Description
OrderedAxisAuthorityFactory(AbstractAuthorityFactory factory, Hints userHints, AxisDirection[] axisOrder) Creates a factory which will reorder the axis of all objects created by the supplied factory.
OrderedAxisAuthorityFactory(String authority, Hints userHints, AxisDirection[] axisOrder) Creates a factory which will reorder the axis of all objects created by the default authority factories.

Method Summary

Modifier and Type	Method and Description
int	compare(Object axis1, Object axis2) Compares two axis for order.
protected AxisDirection	replace(AxisDirection direction) Replaces the specified direction, if applicable.
protected Unit<?>	replace(Unit<?> units) Replaces the specified unit, if applicable.

Methods inherited from class TransformedAuthorityFactory

createFromCoordinateReferenceSystemCodes, dispose, getPriority, replace, replace, replace, replace, replace

Methods inherited from class AuthorityFactoryAdapter

createCartesianCS, createCompoundCRS, createCoordinateOperation, createCoordinateReferenceSystem, createCoordinateSystem, createCoordinateSystemAxis, createCylindricalCS, createDatum, createDerivedCRS, createEllipsoid, createEllipsoidalCS, createEngineeringCRS, createEngineeringDatum, createExtent, createGeocentricCRS, createGeodeticDatum, createGeographicCRS, createImageCRS, createImageDatum, createObject, createOperationMethod, createParameterDescriptor, createPolarCS, createPrimeMeridian, createProjectedCRS, createSphericalCS, createTemporalCRS, createTemporalDatum, createTimeCS, createUnit, createVerticalCRS, createVerticalCS, createVerticalDatum, getAuthority, getAuthorityCodes, getAuthorityFactory, getBackingStoreDescription, getCoordinateOperationAuthorityFactory, getCRSAuthorityFactory, getCSAuthorityFactory, getDatumAuthorityFactory, getDescriptionText, getIdentifiedObjectFinder, getVendor, isAvailable, toBackingFactoryCode

Methods inherited from class AbstractAuthorityFactory

noSuchAuthorityCode, trimAuthority

Methods inherited from class ReferencingFactory

ensureNonNull

Methods inherited from class AbstractFactory

addImplementationHints, equals, getImplementationHints, hashCode, onDeregistration, onRegistration, toString

Methods inherited from class Object

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

Methods inherited from interface CSAuthorityFactory

createCartesianCS, createCoordinateSystem, createCoordinateSystemAxis, createCylindricalCS, createEllipsoidalCS, createPolarCS, createSphericalCS, createTimeCS, createUnit, createVerticalCS

Methods inherited from interface CRSAuthorityFactory

createCompoundCRS, createCoordinateReferenceSystem, createDerivedCRS, createEngineeringCRS, createGeocentricCRS, createGeographicCRS, createImageCRS, createProjectedCRS, createTemporalCRS, createVerticalCRS

Methods inherited from interface AuthorityFactory

createObject, getAuthority, getAuthorityCodes, getDescriptionText

Methods inherited from interface Factory

getVendor

Methods inherited from interface Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Methods inherited from interface Factory

getImplementationHints

Field Detail

forceStandardDirections

protected final boolean forceStandardDirections

true if this authority factory should also force the axis to their standard direction. For example if true, then axis with increasing values toward South will be converted to axis with increasing values toward North. The default value is false.

Since:

2.3

See Also:

Hints.FORCE_STANDARD_AXIS_DIRECTIONS

forceStandardUnits

protected final boolean forceStandardUnits

true if this authority factory should also force all angular units to decimal degrees and linear units to meters. The default value is false.

Since:

2.3

See Also:

Hints.FORCE_STANDARD_AXIS_UNITS

Constructor Detail

OrderedAxisAuthorityFactory

public OrderedAxisAuthorityFactory(String authority,
                                   Hints userHints,
                                   AxisDirection[] axisOrder)
                            throws FactoryRegistryException,
                                   IllegalArgumentException

Creates a factory which will reorder the axis of all objects created by the default authority factories. The factories are fetched using ReferencingFactoryFinder. This constructor accepts the following hints:

• Hints.FORCE_STANDARD_AXIS_UNITS
• Hints.FORCE_STANDARD_AXIS_DIRECTIONS
• All hints understood by ReferencingFactoryFinder

Parameters:

authority - The authority to wraps (example: "EPSG"). If null, then all authority factories must be explicitly specified in the set of hints.

userHints - An optional set of hints, or null if none.

axisOrder - An array of axis directions that determine the axis order wanted, or null for the default axis order.

Throws:

FactoryRegistryException - if at least one factory can not be obtained.

IllegalArgumentException - If at least two axis directions are colinear.

Since:

2.3

OrderedAxisAuthorityFactory

public OrderedAxisAuthorityFactory(AbstractAuthorityFactory factory,
                                   Hints userHints,
                                   AxisDirection[] axisOrder)
                            throws IllegalArgumentException

Creates a factory which will reorder the axis of all objects created by the supplied factory. This constructor accepts the following optional hints:

• Hints.FORCE_STANDARD_AXIS_UNITS
• Hints.FORCE_STANDARD_AXIS_DIRECTIONS

Parameters:

factory - The factory that produces objects using arbitrary axis order.

userHints - An optional set of hints, or null if none.

axisOrder - An array of axis directions that determine the axis order wanted, or null for the default axis order.

Throws:

IllegalArgumentException - If at least two axis directions are colinear.

Since:

2.3

Method Detail

compare

public int compare(Object axis1,
                   Object axis2)

Compares two axis for order. This method is invoked automatically by the replace method for ordering the axis in a coordinate system. The default implementation orders the axis according their direction, using the direction table given at construction time (see also the class description). Subclasses may override this method if they want to define a more sophesticated axis ordering.

Specified by:

compare in interface Comparator

Parameters:

axis1 - The first axis to compare.

axis2 - The second axis to compare.

Returns:

A negative integer if axis1 should appears before axis2, or a positive number if axis2 should appears before axis1, or 0 if the two axis are unordered one relative to the other.

Since:

2.3

replace

protected Unit<?> replace(Unit<?> units)

Replaces the specified unit, if applicable. This method is invoked automatically by the TransformedAuthorityFactory.replace(CoordinateSystem) method. The default implementation replaces the unit only if the FORCE_STANDARD_AXIS_UNITS hint was specified as TRUE at construction time. In such case, the default substitution table is:

• Any linear units converted to meters
• Radians and grades converted to decimal degrees

This default substitution table may be expanded in future Geotools versions.

Overrides:

replace in class TransformedAuthorityFactory

Parameters:

units - The units to replace.

Returns:

The new units, or units if no change were needed.

Since:

2.3

replace

protected AxisDirection replace(AxisDirection direction)

Replaces the specified direction, if applicable. This method is invoked automatically by the TransformedAuthorityFactory.replace(CoordinateSystem) method. The default implementation replaces the direction only if the FORCE_STANDARD_AXIS_DIRECTIONS hint was specified as TRUE at construction time. In such case, the default substitution table is as specified in the AxisDirection.absolute() method. Subclasses may override this method if they want to use a different substitution table.

Overrides:

replace in class TransformedAuthorityFactory

Parameters:

direction - The axis direction to replace.

Returns:

The new direction, or direction if no change were needed.

Since:

2.3