Package org.apache.sis.referencing.datum

Class AbstractDatum

java.lang.Object
org.apache.sis.io.wkt.FormattableObject
org.apache.sis.referencing.AbstractIdentifiedObject
org.apache.sis.referencing.datum.AbstractDatum
All Implemented Interfaces:
Serializable, Formattable, Deprecable, LenientComparable, org.opengis.referencing.datum.Datum, org.opengis.referencing.IdentifiedObject
Direct Known Subclasses:
DefaultEngineeringDatum, DefaultGeodeticDatum, DefaultImageDatum, DefaultParametricDatum, DefaultTemporalDatum, DefaultVerticalDatum
public class AbstractDatum extends AbstractIdentifiedObject implements org.opengis.referencing.datum.Datum
Specifies the relationship of a Coordinate System to the earth. A datum can be defined as a set of real points on the earth that have coordinates. Each datum subtype can be associated with only specific types of coordinate systems, thus creating specific types of coordinate reference system.

Instantiation

This class is conceptually abstract, even if it is technically possible to instantiate it. Typical applications should create instances of the most specific subclass prefixed by Default instead.

Immutability and thread safety

This base class is immutable if the property values (not necessarily the map itself) given to the constructor are also immutable. Most SIS subclasses and related classes are immutable under similar conditions. This means that unless otherwise noted in the javadoc, Datum instances created using only SIS factories and static constants can be shared by many objects and passed between threads without synchronization.
Since:
0.4
Version:
0.7
See Also:

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    (package private) static class 
    AbstractDatum.Simplifier
    A function for simplifying a Datum name before comparison.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private org.opengis.util.InternationalString
    anchorDefinition
    Description, possibly including coordinates, of the point or points used to anchor the datum to the Earth.
    private org.opengis.metadata.extent.Extent
    domainOfValidity
    Area or region in which this datum object is valid.
    private long
    realizationEpoch
    The time after which this datum definition is valid.
    private org.opengis.util.InternationalString
    scope
    Description of domain of usage, or limitations of usage, for which this datum object is valid.
    private static final long
    serialVersionUID
    Serial number for inter-operability with different versions.

    Fields inherited from class org.apache.sis.referencing.AbstractIdentifiedObject

    DEPRECATED_KEY, LOCALE_KEY

    Fields inherited from interface org.opengis.referencing.datum.Datum

    ANCHOR_POINT_KEY, DOMAIN_OF_VALIDITY_KEY, REALIZATION_EPOCH_KEY, SCOPE_KEY

    Fields inherited from interface org.opengis.referencing.IdentifiedObject

    ALIAS_KEY, IDENTIFIERS_KEY, NAME_KEY, REMARKS_KEY

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    (package private)
    AbstractDatum()
    Constructs a new object in which every attributes are set to a null value.
     
    AbstractDatum(Map<String,?> properties)
    Creates a datum from the given properties.
    protected
    AbstractDatum(org.opengis.referencing.datum.Datum datum)
    Creates a new datum with the same values than the specified one.

  • Method Summary

    Modifier and Type
    Method
    Description
    static AbstractDatum
    castOrCopy(org.opengis.referencing.datum.Datum object)
    Returns a SIS datum implementation with the values of the given arbitrary implementation.
    protected long
    computeHashCode()
    Invoked by hashCode() for computing the hash code when first needed.
    boolean
    equals(Object object, ComparisonMode mode)
    Compares the specified object with this datum for equality.
    protected String
    formatTo(Formatter formatter)
    Formats the inner part of the Well Known Text (WKT) representation for this datum.
    org.opengis.util.InternationalString
    getAnchorPoint()
    Returns a description of the point(s) used to anchor the datum to the Earth.
    org.opengis.metadata.extent.Extent
    getDomainOfValidity()
    Returns the region or timeframe in which this datum is valid, or null if unspecified.
    Class<? extends org.opengis.referencing.datum.Datum>
    getInterface()
    Returns the GeoAPI interface implemented by this class.
    Date
    getRealizationEpoch()
    The time after which this datum definition is valid.
    org.opengis.util.InternationalString
    getScope()
    Returns the domain or limitations of usage, or null if unspecified.
    boolean
    isHeuristicMatchForName(String name)
    Returns true if either the primary name or at least one alias matches the given string according heuristic rules.
    private void
    setAnchorPoint(org.opengis.util.InternationalString value)
    Invoked by JAXB only at unmarshalling time.
    private void
    setDomainOfValidity(org.opengis.metadata.extent.Extent value)
    Invoked by JAXB only at unmarshalling time.
    private void
    setRealizationEpoch(Date value)
    Invoked by JAXB only at unmarshalling time.
    private void
    setScope(org.opengis.util.InternationalString value)
    Invoked by JAXB only at unmarshalling time.

    Methods inherited from class org.apache.sis.referencing.AbstractIdentifiedObject

    castOrCopy, equals, formatTo, getAlias, getDescription, getIdentifiers, getName, getRemarks, hashCode, isDeprecated

    Methods inherited from class org.apache.sis.io.wkt.FormattableObject

    print, toString, toString, toWKT

    Methods inherited from class java.lang.Object

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

    Methods inherited from interface org.opengis.referencing.IdentifiedObject

    getAlias, getIdentifiers, getName, getRemarks, toWKT

  • Field Details

    • serialVersionUID

      private static final long serialVersionUID
      Serial number for inter-operability with different versions.
      See Also:

    • anchorDefinition

      private org.opengis.util.InternationalString anchorDefinition
      Description, possibly including coordinates, of the point or points used to anchor the datum to the Earth. Also known as the "origin", especially for Engineering and Image Datums.

      Consider this field as final! This field is modified only at unmarshalling time by setAnchorPoint(InternationalString)

      See Also:

    • realizationEpoch

      private long realizationEpoch
      The time after which this datum definition is valid. This time may be precise (e.g. 1997 for IRTF97) or merely a year (e.g. 1983 for NAD83). If the time is not defined, then the value is Long.MIN_VALUE.

      Consider this field as final! This field is modified only at unmarshalling time by setRealizationEpoch(Date)

    • domainOfValidity

      private org.opengis.metadata.extent.Extent domainOfValidity
      Area or region in which this datum object is valid.

      Consider this field as final! This field is modified only at unmarshalling time by setDomainOfValidity(Extent)

      See Also:

    • scope

      private org.opengis.util.InternationalString scope
      Description of domain of usage, or limitations of usage, for which this datum object is valid.

      Consider this field as final! This field is modified only at unmarshalling time by setScope(InternationalString)

      See Also:

  • Constructor Details

    • AbstractDatum

      public AbstractDatum(Map<String,?> properties)
      Creates a datum from the given properties. The properties given in argument follow the same rules than for the super-class constructor. Additionally, the following properties are understood by this constructor:
      Recognized properties (non exhaustive list)
      Property name Value type Returned by
      "anchorPoint" InternationalString or String getAnchorPoint()
      "realizationEpoch" Date getRealizationEpoch()
      "domainOfValidity" Extent getDomainOfValidity()
      "scope" InternationalString or String getScope()
      Defined in parent class (reminder)
      "name" ReferenceIdentifier or String AbstractIdentifiedObject.getName()
      "alias" GenericName or CharSequence (optionally as array) AbstractIdentifiedObject.getAlias()
      "identifiers" ReferenceIdentifier (optionally as array) AbstractIdentifiedObject.getIdentifiers()
      "remarks" InternationalString or String AbstractIdentifiedObject.getRemarks()
      Parameters:
      properties - the properties to be given to the identified object.

    • AbstractDatum

      protected AbstractDatum(org.opengis.referencing.datum.Datum datum)
      Creates a new datum 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:
      datum - the datum to copy.

    • AbstractDatum

      AbstractDatum()
      Constructs a new object in which every attributes are set to a null value. This is not a valid object. This constructor is strictly reserved to JAXB, which will assign values to the fields using reflection.

  • Method Details

    • castOrCopy

      public static AbstractDatum castOrCopy(org.opengis.referencing.datum.Datum object)
      Returns a SIS datum implementation with the values of the given arbitrary implementation. This method performs the first applicable action in the following choices:
      • If the given object is null, then this method returns null.
      • Otherwise if the given object is an instance of GeodeticDatum, VerticalDatum, TemporalDatum, EngineeringDatum or ImageDatum, then this method delegates to the castOrCopy(…) method of the corresponding SIS subclass. Note that if the given object implements more than one of the above-cited interfaces, then the castOrCopy(…) method to be used is unspecified.
      • Otherwise if the given object is already an instance of AbstractDatum, then it is returned unchanged.
      • Otherwise a new AbstractDatum 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.datum.Datum> getInterface()
      Returns the GeoAPI interface implemented by this class. The default implementation returns Datum.class. Subclasses implementing a more specific GeoAPI interface shall override this method.
      Overrides:
      getInterface in class AbstractIdentifiedObject
      Returns:
      the datum interface implemented by this class.

    • getAnchorPoint

      public org.opengis.util.InternationalString getAnchorPoint()
      Returns a description of the point(s) used to anchor the datum to the Earth. Also known as the "origin", especially for Engineering and Image Datums.
      • For a geodetic datum, the anchor may be the point(s) where the relationship between geoid and ellipsoid is defined.
      • For an engineering datum, the anchor may be an identified physical point with the orientation defined relative to the object.
      • For an image datum, the anchor point may be the centre or the corner of the image.
      • For a temporal datum, see their origin instead.
      Specified by:
      getAnchorPoint in interface org.opengis.referencing.datum.Datum
      Returns:
      description, possibly including coordinates, of the point or points used to anchor the datum to the Earth.

    • getRealizationEpoch

      public Date getRealizationEpoch()
      The time after which this datum definition is valid. This time may be precise or merely a year.

      If an old datum is superseded by a new datum, then the realization epoch for the new datum defines the upper limit for the validity of the old datum.

      Specified by:
      getRealizationEpoch in interface org.opengis.referencing.datum.Datum
      Returns:
      the time after which this datum definition is valid, or null if none.

    • getDomainOfValidity

      public org.opengis.metadata.extent.Extent getDomainOfValidity()
      Returns the region or timeframe in which this datum is valid, or null if unspecified.
      Specified by:
      getDomainOfValidity in interface org.opengis.referencing.datum.Datum
      Returns:
      area or region or timeframe in which this datum is valid, or null.
      See Also:

    • getScope

      public org.opengis.util.InternationalString getScope()
      Returns the domain or limitations of usage, or null if unspecified.
      Specified by:
      getScope in interface org.opengis.referencing.datum.Datum
      Returns:
      description of domain of usage, or limitations of usage, for which this datum object is valid.

    • isHeuristicMatchForName

      public boolean isHeuristicMatchForName(String name)
      Returns true if either the primary name or at least one alias matches the given string according heuristic rules. This method performs the comparison documented in the super-class, with the following additional flexibility:
      • The "D_" prefix (used in ESRI datum names), if presents in the given name or in this datum name, is ignored.
      • If this datum is an instance of DefaultGeodeticDatum, then the prime meridian name may also be ignored.

      Future evolutions

      This method implements heuristic rules learned from experience while trying to provide inter-operability with different data producers. Those rules may be adjusted in any future SIS version according experience gained while working with more data producers.
      Overrides:
      isHeuristicMatchForName in class AbstractIdentifiedObject
      Parameters:
      name - the name to compare.
      Returns:
      true if the primary name or at least one alias matches the specified name.
      See Also:

    • equals

      public boolean equals(Object object, ComparisonMode mode)
      Compares the specified object with this datum for equality. If the mode argument value is STRICT or BY_CONTRACT, then all available properties are compared including the anchor point, realization epoch, domain of validity and the scope.
      Specified by:
      equals in interface LenientComparable
      Overrides:
      equals in class AbstractIdentifiedObject
      Parameters:
      object - the object to compare to this.
      mode - STRICT for performing a strict comparison, or IGNORE_METADATA for comparing only properties relevant to coordinate transformations.
      Returns:
      true if both objects are equal.
      See Also:

    • computeHashCode

      protected long computeHashCode()
      Invoked by hashCode() for computing the hash code when first needed. See AbstractIdentifiedObject.computeHashCode() for more information.
      Overrides:
      computeHashCode in class AbstractIdentifiedObject
      Returns:
      the hash code value. This value may change in any future Apache SIS version.

    • formatTo

      protected String formatTo(Formatter formatter)
      Formats the inner part of the Well Known Text (WKT) representation for this datum. See AbstractIdentifiedObject.formatTo(Formatter) for more information.
      Overrides:
      formatTo in class AbstractIdentifiedObject
      Parameters:
      formatter - the formatter where to format the inner content of this WKT element.
      Returns:
      the CamelCase keyword for the WKT element, or null if unknown.
      See Also:

    • setAnchorPoint

      private void setAnchorPoint(org.opengis.util.InternationalString value)
      Invoked by JAXB only at unmarshalling time.
      See Also:

    • setRealizationEpoch

      private void setRealizationEpoch(Date value)
      Invoked by JAXB only at unmarshalling time.
      See Also:

    • setDomainOfValidity

      private void setDomainOfValidity(org.opengis.metadata.extent.Extent value)
      Invoked by JAXB only at unmarshalling time.
      See Also:

    • setScope

      private void setScope(org.opengis.util.InternationalString value)
      Invoked by JAXB only at unmarshalling time.
      See Also: