# Package org.apache.sis.metadata.iso.spatial

Information about the mechanisms (grid or vector) used to represent spatial data. An explanation for this package is provided in the OpenGIS® javadoc. The remaining discussion on this page is specific to the SIS implementation.
Overview
For a global overview of metadata in SIS, see the `org​.apache​.sis​.metadata` package javadoc.

Package overview
Class hierarchy | Aggregation hierarchy
--- | ---
ISO 19115 metadata `├─` Spatial representation «abstract» `│ ├─` Vector spatial representation `│ └─` Grid spatial representation `│ ├─` Georeferenceable `│ └─` Georectified `├─` Geolocation information «abstract» `│ └─` GCP collection `├─` GCP `├─` Dimension `└─` Geometric objects Code list `├─` Topology level `├─` Geometric object type `├─` Cell geometry `├─` Pixel orientation `├─` Dimension name type `└─` Spatial representation type | Spatial representation «abstract» Vector spatial representation `├─` Topology level «code list» `└─` Geometric objects `└─` Geometric object type «code list» Grid spatial representation `├─` Dimension `│ └─` Dimension name type «code list» `└─` Cell geometry «code list» Georeferenceable `└─` Geolocation information «abstract» Georectified `├─` Pixel orientation «code list» `└─` GCP GCP collection Spatial representation type «code list»

Null values, nil objects and collections
All constructors and setter methods accept `null` arguments. A null argument value means that the metadata element can not be provided, and the reason for that is unspecified. Alternatively, users can specify why a metadata element is missing by providing a value created by `NilReason​.createNilObject(Class)`.

Unless otherwise noted in the Javadoc, all getter methods may return an empty collection, an empty array or `null` if the type is neither a collection or an array. Note that non-null values may be `NilObject`s.

Unless the metadata object has been marked as unmodifiable and unless otherwise noted in the Javadoc, all collections returned by getter methods are live: adding new elements in the collection modify directly the underlying metadata object.

Since:
  0.3

Defined in the `sis-metadata` module

- Class Summary
  Class | Description
  --- | ---
  AbstractGeolocationInformation | Information used to determine geographic location corresponding to image location.
  AbstractSpatialRepresentation | Method used to represent geographic information in the dataset.
  DefaultDimension | Axis properties.
  DefaultGCP | Information on ground control point.
  DefaultGCPCollection | Information about a control point collection.
  DefaultGeometricObjects | Number of objects, listed by geometric object type, used in the dataset.
  DefaultGeorectified | Grid whose cells are regularly spaced in a geographic or projected coordinate reference system.
  DefaultGeoreferenceable | Grid with cells irregularly spaced in any given geographic/map projection coordinate reference system.
  DefaultGridSpatialRepresentation | Method used to represent geographic information in the dataset.
  DefaultVectorSpatialRepresentation | Information about the vector spatial objects in the dataset.