java.lang.Object
- com.esri.arcgisruntime.geometry.SpatialReference

All Implemented Interfaces:

JsonSerializable
```
public final class SpatialReference
extends Object
implements JsonSerializable
```
Defines how coordinates correspond to locations in the real world. Instances of this class represent a specific coordinate system, identified by a well-known ID (WKID) number or well-known text (WKT) string. SpatialReferences are immutable.
SpatialReferences allow disparate spatial data to be consistently viewed and analyzed together. Geometry, Layer, and GraphicsOverlay classes have a SpatialReference that determines the system in which the data is stored, and the SpatialReference of each GeoView determines how it displays the data it contains. There are two main categories of coordinate system that can be represented by a SpatialReference:
- Geographic coordinate systems use a three-dimensional spherical surface to define locations on the earth. Coordinates are defined using angular units such as degrees. The isGeographic() method returns true for spatial references with a geographic coordinate system.
- Projected coordinate systems use a flat, two-dimensional surface to define locations on the earth. Coordinates are defined using linear units such as meters or miles. The isProjected() method returns true for spatial references with a projected coordinate system.
Use the create(int) constructor to create a SpatialReference by specifying the WKID of a coordinate system, or use the static members of SpatialReferences to return instances of the most commonly-used SpatialReferences.
A SpatialReference can also include a vertical coordinate system, that can be set when you create a projected or geographic coordinate system by using the create(int, int) constructor.
For more information about spatial references, see the 'Fundamentals' > 'Spatial references' topic in the Guide.
Since:

100.0.0

See Also:

Geometry.getSpatialReference(), SpatialReferences, GeoModel.getSpatialReference(), FeatureTable.getSpatialReference(), Layer.getSpatialReference()

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`static SpatialReference`	`create(int wkid)`	Creates a new spatial reference from the given well-known ID (WKID) number.
`static SpatialReference`	`create(int wkid, int verticalWkid)`	Creates a new spatial reference with the given well-known ID (WKID) numbers for both a horizontal and a vertical coordinate system.
`static SpatialReference`	`create(String wkText)`	Creates a new spatial reference from the given well-known text (WKT) string.
`boolean`	`equals(Object obj)`
`static SpatialReference`	`fromJson(String json)`	Creates a SpatialReference instance from a JSON string.
`SpatialReference`	`getBaseGeographic()`	Gets the underlying geographic coordinate system of this spatial reference.
`double`	`getConvergenceAngle(Point point)`	Gets the calculated grid convergence angle for a given point, which is the angle between True North and Grid North.
`Unit`	`getUnit()`	Gets the units of measurement defined by this instance.
`Map<String,Object>`	`getUnknownJson()`	SpatialReferences never have any unknown JSON so this returns an empty Map.
`Map<String,Object>`	`getUnsupportedJson()`	SpatialReferences never have any unsupported JSON so this returns an empty Map.
`LinearUnit`	`getVerticalUnit()`	Gets the unit of measure for the vertical coordinate system of this spatial reference.
`int`	`getVerticalWkid()`	Gets the well-known ID (WKID) number of the vertical coordinate system of this instance.
`int`	`getWkid()`	Gets the well-known ID (WKID) number of this instance.
`String`	`getWKText()`	Gets the well-known text (WKT) representation of this instance.
`int`	`hashCode()`
`boolean`	`hasVertical()`	Indicates if this instance has a vertical coordinate system set.
`boolean`	`isGeographic()`	Indicates if this instance represents a geographic coordinate system.
`boolean`	`isPannable()`	Indicates if an ArcGISMap with this SpatialReference can be continuously horizontally pannable.
`boolean`	`isProjected()`	Indicates if this instance represents a projected coordinate system.
`String`	`toJson()`	Serializes this object to a JSON string.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - create
```
public static SpatialReference create(int wkid)
```
    Creates a new spatial reference from the given well-known ID (WKID) number.
    The WKID refers to a specific coordinate system. WKIDs are defined by standards bodies or organizations. ArcGIS supports a variety of WKIDs, typically those defined by the European Petroleum Survey Group (EPSG) or Esri, as well as a few other commonly used IDs.
    SpatialReferences can also be created from a well-known text (WKT) string using create(String). Alternatively, use the static methods on SpatialReferences to return instances of the most commonly-used SpatialReferences.
    
    Parameters:
    
    wkid - the WKID number of the required SpatialReference
    
    Returns:
    
    a SpatialReference with the given WKID number
    
    Since:
    
    100.0.0
    
    See Also:
    
    getWkid()
  - create
```
public static SpatialReference create(String wkText)
```
    Creates a new spatial reference from the given well-known text (WKT) string.
    WKTs are full-text definitions of all of the parameters that specify a spatial reference.
    SpatialReferences can also be created from a well-known ID (WKID number) string using create(int). Alternatively, use the static methods on SpatialReferences to return instances of the most commonly-used SpatialReferences.
    
    Parameters:
    
    wkText - a string containing a well-known text representation of a SpatialReference
    
    Returns:
    
    a SpatialReference based on the given WKT string
    
    Since:
    
    100.0.0
    
    See Also:
    
    getWKText()
  - create
```
public static SpatialReference create(int wkid,
                                      int verticalWkid)
```
    Creates a new spatial reference with the given well-known ID (WKID) numbers for both a horizontal and a vertical coordinate system. Vertical coordinate systems are not spatial references themselves, but control how z values are displayed.
    
    Parameters:
    
    wkid - the WKID number of the required horizontal SpatialReference
    
    verticalWkid - the WKID number of the required vertical SpatialReference
    
    Returns:
    
    a SpatialReference with the given WKID numbers
    
    Since:
    
    100.0.0
    
    See Also:
    
    getWkid(), getVerticalWkid()
  - fromJson
```
public static SpatialReference fromJson(String json)
```
    Creates a SpatialReference instance from a JSON string.
    
    Parameters:
    
    json - a JSON string that represents a SpatialReference
    
    Returns:
    
    a SpatialReference instance
    
    Throws:
    
    IllegalArgumentException - if json is null or empty
    
    Since:
    
    100.0.0
  - toJson
```
public String toJson()
```
    Description copied from interface: JsonSerializable
    
    Serializes this object to a JSON string. Note that unknown JSON is omitted from the serialized string.
    
    Specified by:
    
    toJson in interface JsonSerializable
    
    Returns:
    
    a JSON string
  - getUnknownJson
```
public Map<String,Object> getUnknownJson()
```
    SpatialReferences never have any unknown JSON so this returns an empty Map.
    
    Specified by:
    
    getUnknownJson in interface JsonSerializable
    
    Returns:
    
    an empty unmodifiable Map
    
    Since:
    
    100.0.0
  - getUnsupportedJson
```
public Map<String,Object> getUnsupportedJson()
```
    SpatialReferences never have any unsupported JSON so this returns an empty Map.
    
    Specified by:
    
    getUnsupportedJson in interface JsonSerializable
    
    Returns:
    
    an empty unmodifiable Map
    
    Since:
    
    100.0.0
  - getWkid
```
public int getWkid()
```
    Gets the well-known ID (WKID) number of this instance. WKIDs are unique numbers that refer to a specific predefined coordinate system.
    
    Returns:
    
    The WKID number of the coordinate system this instance represents. Returns 0 if this instance represents a custom coordinate system, or -1 if it is invalid.
    
    Since:
    
    100.0.0
    
    See Also:
    
    create(int)
  - getVerticalUnit
```
public LinearUnit getVerticalUnit()
```
    Gets the unit of measure for the vertical coordinate system of this spatial reference.
    Is null if hasVertical() is false.
    
    Returns:
    
    the unit of measure for the vertical coordinate system of this spatial reference, or null if none
    
    Since:
    
    100.14.0
  - getVerticalWkid
```
public int getVerticalWkid()
```
    Gets the well-known ID (WKID) number of the vertical coordinate system of this instance. WKIDs are unique numbers that refer to a specific predefined coordinate system.
    
    Returns:
    
    The WKID number of the vertical coordinate system this instance represents. Returns 0 if a vertical coordinate system was not set when this instance was created. Returns -1 if an invalid vertical coordinate system was specified.
    
    Since:
    
    100.0.0
    
    See Also:
    
    getWkid(), create(int, int)
  - getBaseGeographic
```
public SpatialReference getBaseGeographic()
```
    Gets the underlying geographic coordinate system of this spatial reference. Intended for use when this spatial reference is a projected coordinate system. If this spatial reference is a geographic coordinate system then a new reference to itself is returned.
    
    Returns:
    
    the underlying geographic coordinate system
    
    Since:
    
    100.1.0
    
    See Also:
    
    isGeographic(), isProjected()
  - hasVertical
```
public boolean hasVertical()
```
    Indicates if this instance has a vertical coordinate system set.
    A spatial reference can optionally include a definition for a vertical coordinate system (VCS), which can be used to interpret the z values of a geometry (Point.getZ()). A VCS defines linear units of measure, the origin of z values, and whether z values are "positive up" (representing heights above a surface) or "positive down" (indicating that values are depths below a surface).
    A SpatialReference may have a VCS set, for example if it was created using create(int, int). getVerticalWkid() and getWKText() provide more information about the specific VCS set on this instance.
    VCSs are used when projecting geometries using a HorizontalVerticalTransformation.
    
    Returns:
    
    true if this instance has a vertical coordinate system set, false otherwise.
    
    Since:
    
    100.9.0
    
    See Also:
    
    getVerticalWkid()
  - isGeographic
```
public boolean isGeographic()
```
    Indicates if this instance represents a geographic coordinate system. Geographic coordinate systems use angular units to define coordinates.
    
    Returns:
    
    true if this instance represents a geographic coordinate system, false otherwise
    
    Since:
    
    100.0.0
    
    See Also:
    
    isProjected(), getUnit()
  - isProjected
```
public boolean isProjected()
```
    Indicates if this instance represents a projected coordinate system. Projected coordinate systems use linear units to define coordinates.
    
    Returns:
    
    true if this instance represents a projected coordinate system; false otherwise
    
    Since:
    
    100.0.0
    
    See Also:
    
    isProjected(), getUnit()
  - isPannable
```
public boolean isPannable()
```
    Indicates if an ArcGISMap with this SpatialReference can be continuously horizontally pannable. A continuously pannable spatial reference is one of the requirements for a wrap-around map, where a user is able to continuously pan the map across the anti-meridian (approximately equal to the international date line). Only the two most common coordinate systems are continuously pannable; WGS 1984 (WKID 4326), and Web Mercator Auxilliary Sphere (WKID 102113, 102100, or 3857).
    
    Returns:
    
    true if continuously horizontally pannable; false otherwise
    
    Since:
    
    100.0.0
    
    See Also:
    
    GeoView.isWrapAroundEnabled(), MapView.getWrapAroundMode()
  - getWKText
```
public String getWKText()
```
    Gets the well-known text (WKT) representation of this instance. WKTs are full-text definitions of all of the parameters that specify a spatial reference.
    SpatialReferences can be created from a WKT string using create(String).
    
    Returns:
    
    a string containing a WKT representation of this instance
    
    Since:
    
    100.0.0
  - getUnit
```
public Unit getUnit()
```
    Gets the units of measurement defined by this instance. The Unit of the SpatialReference of a Geometry or Layer determine the units used by its coordinates.
    
    Returns:
    
    the units of measurement of this instance
    
    Since:
    
    100.0.0
    
    See Also:
    
    Unit.getUnitType(), isGeographic(), isProjected()
  - getConvergenceAngle
```
public double getConvergenceAngle(Point point)
```
    Gets the calculated grid convergence angle for a given point, which is the angle between True North and Grid North.
    This value can be used to convert a horizontal direction expressed as an azimuth in a geographic coordinate system (relative to True North) to a direction expressed as a bearing in a projected coordinate system (relative to Grid North), and vice versa.
    The grid convergence returned by this method is positive when Grid North lies east of True North, following the Gauss-Bomford convention. The formula bearing = azimuth - convergence can be used to obtain a bearing from an azimuth using the grid convergence.
    This sign convention is sometimes named the Gauss-Bomford convention. Other notes:
    
    Returns 0 if the spatial reference is a geographic coordinate system
    Returns NAN if the point is outside the projection's horizon or on error
    If the point has no spatial reference, it is assumed to be in the given spatial reference
    If the point's spatial reference differs from the spatial reference given, its location will be transformed automatically to the given spatial reference
    Parameters:
    
    point - the point at which to calculate the convergence. If this point has a different spatial reference, it will be reprojected to this spatial reference; if the spatial reference is null, the point is assumed to already be defined in this spatial reference.
    
    Returns:
    
    the convergence angle in degrees. Returns 0 if this spatial reference represents a geographic coordinate system (isGeographic() is true). Returns Double.NaN if the point lies outside this spatial reference's horizon.
    
    Throws:
    
    IllegalArgumentException - if point is null
    
    Since:
    
    100.3.0
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - equals
```
public boolean equals(Object obj)
```
    Overrides:
    
    equals in class Object

Class SpatialReference

Method Summary

Methods inherited from class java.lang.Object

Method Detail

create

create

create

fromJson

toJson

getUnknownJson

getUnsupportedJson

getWkid

getVerticalUnit

getVerticalWkid

getBaseGeographic

hasVertical

isGeographic

isProjected

isPannable

getWKText

getUnit

getConvergenceAngle

hashCode

equals