# Class DefaultGCP

Object
AbstractMetadata
ModifiableMetadata
ISOMetadata
DefaultGCP

All Implemented Interfaces:
  `Serializable`, `Emptiable`, `LenientComparable`, `IdentifiedObject`, `GCP`

public class DefaultGCP extends ISOMetadata implements GCP
Information on ground control point. Ground control points (GCP) are large marked targets on the ground, not to be confused with localization grid points embedded in some file formats like GeoTIFF or netCDF. The following property is mandatory in a well-formed metadata according ISO 19115:
`MI_GCP` `└─geographicCoordinates……` Geographic or map position of the control point, in either two or three dimensions.

## Limitations

- Instances of this class are not synchronized for multi-threading. Synchronization, if needed, is caller's responsibility.
- Serialized objects of this class are not guaranteed to be compatible with future Apache SIS releases. Serialization support is appropriate for short term storage or RMI between applications running the same version of Apache SIS. For long term storage, use `XML` instead.

Since:
  0.3
See Also:
  - `DefaultGCPCollection`
  - Serialized Form

- ## Nested Class Summary

  ### Nested classes/interfaces inherited from class ModifiableMetadata

  `ModifiableMetadata​.State`

- ## Field Summary

  ### Fields inherited from class ISOMetadata

  `identifiers`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `DefaultGCP()`
  Constructs an initially empty ground control point.
  `DefaultGCP(GCP object)`
  Constructs a new instance initialized with the values from the specified metadata object.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `static DefaultGCP`
  `castOrCopy(GCP object)`
  Returns a SIS metadata implementation with the values of the given arbitrary implementation.
  `Collection<Element>`
  `getAccuracyReports()`
  Returns the accuracy of a ground control point.
  `DirectPosition`
  `getGeographicCoordinates()`
  Returns the geographic or map position of the control point, in either two or three dimensions.
  `void`
  `setAccuracyReports(Collection<? extends Element> newValues)`
  Sets the accuracy of a ground control point.
  `void`
  `setGeographicCoordinates(DirectPosition newValue)`
  Sets the geographic or map position of the control point, in either two or three dimensions.

  ### Methods inherited from class ISOMetadata

  `getIdentifier, getIdentifierMap, getIdentifiers, getStandard, setIdentifier`

  ### Methods inherited from class ModifiableMetadata

  `checkWritePermission, collectionType, copyCollection, copyList, copyMap, copySet, deepCopy, nonNullCollection, nonNullList, nonNullMap, nonNullSet, singleton, state, writeCollection, writeList, writeMap, writeSet`

  ### Methods inherited from class AbstractMetadata

  `asMap, asTreeTable, clone, equals, equals, getInterface, hashCode, isEmpty, nilReasons, prune, toString`

  ### Methods inherited from class Object

  `finalize, getClass, notify, notifyAll, wait, wait, wait`

- ## Constructor Details

  - ### DefaultGCP

    public DefaultGCP()
    Constructs an initially empty ground control point.

  - ### DefaultGCP

    public DefaultGCP(GCP object)
    Constructs a new instance initialized with the values from the specified metadata object. This is a shallow copy constructor, because the other metadata contained in the given object are not recursively copied.
    Parameters:
      `object` - the metadata to copy values from, or `null` if none.
    See Also:
      - `castOrCopy(GCP)`

- ## Method Details

  - ### castOrCopy

    public static DefaultGCP castOrCopy(GCP object)
    Returns a SIS metadata 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 already an instance of `DefaultGCP`, then it is returned unchanged.
    - Otherwise a new `DefaultGCP` instance is created using the copy constructor and returned. Note that this is a shallow copy operation, because the other metadata 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.

  - ### getGeographicCoordinates

    public DirectPosition getGeographicCoordinates()
    Returns the geographic or map position of the control point, in either two or three dimensions.
    Specified by:
      `getGeographicCoordinates` in interface `GCP`
    Returns:
      geographic or map position of the control point, or `null`.
    "TODO:"
      finish the annotation on the referencing module before.

  - ### setGeographicCoordinates

    public void setGeographicCoordinates(DirectPosition newValue)
    Sets the geographic or map position of the control point, in either two or three dimensions.
    Parameters:
      `newValue` - the new geographic coordinates values.

  - ### getAccuracyReports

    public Collection<Element> getAccuracyReports()
    Returns the accuracy of a ground control point.
    Specified by:
      `getAccuracyReports` in interface `GCP`
    Returns:
      accuracy of a ground control point.

  - ### setAccuracyReports

    public void setAccuracyReports(Collection<? extends Element> newValues)
    Sets the accuracy of a ground control point.
    Parameters:
      `newValues` - the new accuracy report values.