Package org.apache.sis.referencing.operation

Class DefaultTransformation

java.lang.Object
org.apache.sis.io.wkt.FormattableObject
org.apache.sis.referencing.AbstractIdentifiedObject
org.apache.sis.referencing.operation.AbstractCoordinateOperation
org.apache.sis.referencing.operation.DefaultTransformation
All Implemented Interfaces:
Serializable, Formattable, Parameterized, Deprecable, LenientComparable, org.opengis.referencing.IdentifiedObject, org.opengis.referencing.operation.CoordinateOperation, org.opengis.referencing.operation.SingleOperation, org.opengis.referencing.operation.Transformation
public class DefaultTransformation extends AbstractCoordinateOperation implements org.opengis.referencing.operation.Transformation
A parameterized mathematical operation that transforms coordinates to another CRS with a change of datum. The parameters of a coordinate transformation are empirically derived from data containing the coordinates of a series of points in both coordinate reference systems. This computational process is usually "over-determined", allowing derivation of error (or accuracy) estimates for the transformation. Also, the stochastic nature of the parameters may result in multiple (different) versions of the same coordinate transformation.

This coordinate operation contains an operation method, usually with associated parameter values. In the SIS default implementation, the parameter values are inferred from the math transform. Subclasses may have to override the SingleOperation.getParameterValues() method if they need to provide a different set of parameters.

Immutability and thread safety

This class is immutable and thus thread-safe if the property values (not necessarily the map itself) given to the constructor are also immutable. This means that unless otherwise noted in the javadoc, Transformation instances created using only SIS factories and static constants can be shared by many objects and passed between threads without synchronization.
Since:
0.6
Version:
0.6
Author:
Martin Desruisseaux (IRD, Geomatys)
See Also:

  • Constructor Details

    • DefaultTransformation

      public DefaultTransformation(Map<String,?> properties, org.opengis.referencing.crs.CoordinateReferenceSystem sourceCRS, org.opengis.referencing.crs.CoordinateReferenceSystem targetCRS, org.opengis.referencing.crs.CoordinateReferenceSystem interpolationCRS, org.opengis.referencing.operation.OperationMethod method, org.opengis.referencing.operation.MathTransform transform)
      Creates a coordinate transformation from the given properties. The properties given in argument follow the same rules than for the super-class constructor. The following table is a reminder of main (not all) properties:
      Recognized properties (non exhaustive list)
      Property name Value type Returned by
      "name" Identifier or String AbstractIdentifiedObject.getName()
      "identifiers" Identifier (optionally as array) AbstractIdentifiedObject.getIdentifiers()
      "coordinateOperationAccuracy" PositionalAccuracy (optionally as array) AbstractCoordinateOperation.getCoordinateOperationAccuracy()
      "domainOfValidity" Extent AbstractCoordinateOperation.getDomainOfValidity()
      Parameters:
      properties - the properties to be given to the identified object.
      sourceCRS - the source CRS.
      targetCRS - the target CRS.
      interpolationCRS - the CRS of additional coordinates needed for the operation, or null if none.
      method - the coordinate operation method (mandatory in all cases).
      transform - transform from positions in the source CRS to positions in the target CRS.

    • DefaultTransformation

      protected DefaultTransformation(org.opengis.referencing.operation.Transformation operation)
      Creates a new coordinate operation with the same values than the specified one. This copy constructor provides a way to convert an arbitrary implementation into a SIS 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:
      operation - the coordinate operation to copy.
      See Also:

  • Method Details

    • castOrCopy

      public static DefaultTransformation castOrCopy(org.opengis.referencing.operation.Transformation object)
      Returns a SIS coordinate operation implementation with the values of the given arbitrary implementation. If the given object is already an instance of DefaultTransformation, then it is returned unchanged. Otherwise a new DefaultTransformation instance is created using the copy constructor and returned. Note that this is a shallow copy operation, because the other properties contained in the given object are not recursively copied.
      Parameters:
      object - the object to get as a SIS implementation, or null if none.
      Returns:
      a SIS implementation containing the values of the given object (may be the given object itself), or null if the argument was null.

    • getInterface

      public Class<? extends org.opengis.referencing.operation.Transformation> getInterface()
      Returns the GeoAPI interface implemented by this class. The SIS implementation returns Transformation.class.
      Note for implementers: Subclasses usually do not need to override this method since GeoAPI does not define Transformation sub-interface. Overriding possibility is left mostly for implementers who wish to extend GeoAPI with their own set of interfaces.
      Overrides:
      getInterface in class AbstractCoordinateOperation
      Returns:
      Transformation.class or a user-defined sub-interface.

    • getMethod

      public org.opengis.referencing.operation.OperationMethod getMethod()
      Returns a description of the operation method, including a list of expected parameter names. The returned object does not contains any parameter value.
      Specified by:
      getMethod in interface org.opengis.referencing.operation.SingleOperation
      Returns:
      a description of the operation method.

    • getParameterDescriptors

      public org.opengis.parameter.ParameterDescriptorGroup getParameterDescriptors()
      Returns a description of the parameters. The default implementation performs the following choice:
      • If parameter values were specified explicitly at construction time, then the descriptor of those parameters is returned.
      • Otherwise if this method can infer the parameter descriptor from the math transform, then that descriptor is returned.
      • Otherwise fallback on the method parameters.
      Note: the two parameter descriptions (from the MathTransform or from the OperationMethod) should be very similar. If they differ, it should be only in minor details like remarks, default values or units of measurement.
      Specified by:
      getParameterDescriptors in interface Parameterized
      Returns:
      a description of the parameters.
      See Also:

    • getParameterValues

      public org.opengis.parameter.ParameterValueGroup getParameterValues()
      Returns the parameter values. The default implementation performs the following choice:
      Specified by:
      getParameterValues in interface Parameterized
      Specified by:
      getParameterValues in interface org.opengis.referencing.operation.SingleOperation
      Returns:
      the parameter values.
      Throws:
      UnsupportedOperationException - if the parameter values cannot be determined for the current math transform implementation.
      See Also:

    • equals

      public boolean equals(Object object, ComparisonMode mode)
      Compares this coordinate operation with the specified object for equality. If the mode argument is ComparisonMode.STRICT or BY_CONTRACT, then all available properties are compared including the domain of validity and the scope.
      Specified by:
      equals in interface LenientComparable
      Overrides:
      equals in class AbstractCoordinateOperation
      Parameters:
      object - the object to compare to this.
      mode - STRICT for performing a strict comparison, or IGNORE_METADATA for ignoring properties that do not make a difference in the numerical results of coordinate operations.
      Returns:
      true if both objects are equal for the given comparison mode.
      See Also: