org.apache.sis.referencing.operation

Class CoordinateOperationContext

Object

CoordinateOperationContext

All Implemented Interfaces:

Serializable

public class CoordinateOperationContext
extends Object
implements Serializable

Optional information about the context in which a requested coordinate operation will be used. The context can provide information such as:

• The geographic area where the transformation will be used.
• The desired accuracy. A coarser accuracy may allow SIS to choose a faster transformation method.

While optional, those information can help Default­Coordinate­Operation­Factory to choose the most suitable coordinate transformation between two CRS.

Example: if a transformation from NAD27 to WGS84 is requested without providing context, then Apache SIS will return the transformation applicable to the widest North American surface. But if the user provides a context saying that he wants to transform coordinates in Texas, then Apache SIS may return another coordinate transformation with different Bursa-Wolf parameters more suitable to Texas, but not suitable to the rest of North-America.

Coordinate­Operation­Context is part of the API used by SIS for implementing the late binding model. See package javadoc for a note on early binding versus late binding implementations.

Since:

0.7

See Also:

Serialized Form

Defined in the sis-referencing module

TODO:

Should also take the country of a Locale. The EPSG database contains ISO2 and ISO3 identifiers that we can use.

Constructor Summary

Constructors

Constructor and Description
CoordinateOperationContext() Creates a new context with no area of interest and the best accuracy available.
CoordinateOperationContext(Extent area, double accuracy) Creates a new context with the given area of interest and desired accuracy.

Method Summary

Methods

Modifier and Type	Method and Description
Extent	getAreaOfInterest() Returns the spatio-temporal area of interest, or null if none.
double	getDesiredAccuracy() Returns the desired accuracy in metres.
void	setAreaOfInterest(Extent area) Sets the spatio-temporal area of interest, or null if none.
void	setAreaOfInterest(GeographicBoundingBox area) Sets the geographic component of the area of interest, or null if none.
void	setDesiredAccuracy(double accuracy) Sets the desired accuracy in metres.

Methods inherited from class Object

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

Constructor Detail

CoordinateOperationContext

public CoordinateOperationContext()

Creates a new context with no area of interest and the best accuracy available.

CoordinateOperationContext

public CoordinateOperationContext(Extent area,
                          double accuracy)

Creates a new context with the given area of interest and desired accuracy.

Parameters:

area - the area of interest, or null if none.

accuracy - the desired accuracy in metres, or 0 for the best accuracy available. See get­Desired­Accuracy() for more details about what we mean by "best accuracy".

Method Detail

getAreaOfInterest

public Extent getAreaOfInterest()

Returns the spatio-temporal area of interest, or null if none.

Returns:

the spatio-temporal area of interest, or null if none.

See Also:

Extents.get­Geographic­Bounding­Box(Extent)

setAreaOfInterest

public void setAreaOfInterest(Extent area)

Sets the spatio-temporal area of interest, or null if none.

Parameters:

area - the spatio-temporal area of interest, or null if none.

setAreaOfInterest

public void setAreaOfInterest(GeographicBoundingBox area)

Sets the geographic component of the area of interest, or null if none. This convenience method set the bounding box into the spatio-temporal Extent.

The reverse operation can be done with Extents.get­Geographic­Bounding­Box(get­Area­Of­Interest()).

Parameters:

area - the geographic area of interest, or null if none.

getDesiredAccuracy

public double getDesiredAccuracy()

Returns the desired accuracy in metres. A value of 0 means to search for the most accurate operation.

When searching for the most accurate operation, SIS considers only the operations specified by the authority. For example the Molodensky method is a better datum shift approximation than Abridged Molodensky. But if all coordinate operations defined by the authority use the Abridged Molodensky method, then SIS will ignore the Molodensky one.

Returns:

the desired accuracy in metres.

setDesiredAccuracy

public void setDesiredAccuracy(double accuracy)

Sets the desired accuracy in metres. A value of 0 means to search for the most accurate operation. See get­Desired­Accuracy() for more details about what we mean by "most accurate".

Parameters:

accuracy - the desired accuracy in metres.