@UML(identifier="GM_Object", specification=ISO_19107) public interface Geometry extends TransfiniteSet
Geometry
supports interfaces common
to all geographically referenced geometric objects. Geometry
instances are sets
of direct positions in a particular coordinate reference system. A Geometry
can
be regarded as an infinite set of points that satisfies the set operation interfaces for a set
of direct positions, TransfiniteSet<DirectPosition>
.Modifier and Type  Method and Description 

Geometry 
clone()
Returns a clone of this geometry with deep copy semantic.

double 
distance(Geometry geometry)
Returns the distance between this
Geometry and another Geometry . 
Boundary 
getBoundary()
Returns a finite set of
Geometry s containing all of the direct positions on the
boundary of this Geometry . 
Geometry 
getBuffer(double distance)
Returns a
Geometry containing all points whose distance from this
Geometry is less than or equal to the distance passed as a parameter. 
DirectPosition 
getCentroid()
Returns the mathematical centroid for this
Geometry . 
Complex 
getClosure()
Returns a finite set of
Geometry s containing all of the points on the boundary of
this Geometry and this object (the union of the object and its boundary). 
Geometry 
getConvexHull()
Returns a
Geometry that represents the convex hull of this Geometry . 
int 
getCoordinateDimension()
Returns the dimension of the coordinates that define this
Geometry , which must
be the same as the coordinate dimension of the coordinate reference system for this
Geometry . 
CoordinateReferenceSystem 
getCoordinateReferenceSystem()
Returns the coordinate reference system used in direct position
coordinates.

int 
getDimension(DirectPosition point)
Returns the inherent dimension of this
Geometry , which shall be less than or
equal to the coordinate dimension. 
Envelope 
getEnvelope()
Returns the minimum bounding box for this
Geometry . 
Set<? extends Complex> 
getMaximalComplex()
Returns the set of maximal complexes within which this
Geometry is contained. 
Geometry 
getMbRegion()
Returns a region in the coordinate reference system that contains this
Geometry . 
Precision 
getPrecision()
Returns the precision model used to guide the accuracy of topology operations.

DirectPosition 
getRepresentativePoint()
Returns a point value that is guaranteed to be on this
Geometry . 
boolean 
isCycle()
Returns
true if this Geometry has an empty boundary after topological
simplification (removal of overlaps between components in nonstructured aggregates, such as
subclasses of Aggregate ). 
boolean 
isMutable()
Returns
false if this geometry is immutable. 
boolean 
isSimple()
Returns
true if this Geometry has no interior point of
selfintersection or selftangency. 
Geometry 
toImmutable()
Returns an immutable copy of this geometry.

Geometry 
transform(CoordinateReferenceSystem newCRS)
Returns a new
Geometry that is the coordinate transformation of this
Geometry into the passed coordinate reference system within the accuracy
of the transformation. 
Geometry 
transform(CoordinateReferenceSystem newCRS,
MathTransform transform)
Returns a new
Geometry that is the coordinate transformation of this
Geometry into the passed coordinate reference system, using the
specified transform. 
contains, contains, difference, equals, intersection, intersects, symmetricDifference, union
@UML(identifier="CRS", obligation=MANDATORY, specification=ISO_19107) CoordinateReferenceSystem getCoordinateReferenceSystem()
null
, then this Geometry
uses the coordinate reference
system from another Geometry
in which it is contained.
The most common example where the coordinate reference system is null
is the elements
and subcomplexes of a maximal complex. The complex can
carry the coordinate reference system for all
primitive elements
and for all Complex
subcomplexes.
This association is only navigable from Geometry
to coordinate reference system. This means that the coordinate reference system objects in a data set do
not keep a list of Geometry
s that use them.
getCoordinateDimension()
Precision getPrecision()
@UML(identifier="mbRegion", obligation=MANDATORY, specification=ISO_19107) Geometry getMbRegion()
Geometry
.
The default shall be to return an instance of an appropriate Geometry
subclass
that represents the same spatial set returned from getEnvelope()
. The most common
use of mbRegion
will be to support indexing methods that use extents other
than minimum bounding rectangles (MBR or envelopes). This does not restrict the returned
Geometry
from being a nonvector geometric representation, although those
types are not defined within this specification.getEnvelope()
,
getBoundary()
@UML(identifier="representativePoint", obligation=MANDATORY, specification=ISO_19107) DirectPosition getRepresentativePoint()
Geometry
. The default
logic may be to use the direct position of the point returned by
getCentroid()
if that point is on the object. Another use of representative point may
be for the placement of labels in systems based on graphic presentation.getCentroid()
@UML(identifier="boundary", obligation=MANDATORY, specification=ISO_19107) Boundary getBoundary()
Geometry
s containing all of the direct positions on the
boundary of this Geometry
. These object collections shall have further internal
structure where appropriate. The finite set of Geometry
s returned shall be in
the same coordinate reference system as this Geometry
. If the Geometry
is in a complex, then the boundary Geometry
s returned shall be
in the same complex. If the Geometry
is not in any
complex, then the boundary Geometry
s returned may have been
constructed in response to the operation. The elements of a boundary shall be smaller in
dimension than the original element.getMbRegion()
,
getClosure()
,
getBuffer(double)
,
#getDistance
@UML(identifier="closure", obligation=MANDATORY, specification=ISO_19107) Complex getClosure()
Geometry
s containing all of the points on the boundary of
this Geometry
and this object (the union of the object and its boundary). These
object collections shall have further internal structure where appropriate. The finite set
of Geometry
s returned shall be in the same coordinate reference system as this
Geometry
. If the Geometry
is in a complex, then the boundary
Geometry
s returned shall be in the same complex. If the
Geometry
is not in any complex, then the boundary
Geometry
s returned may have been constructed in response to the operation.getBoundary()
@UML(identifier="isSimple", obligation=MANDATORY, specification=ISO_19107) boolean isSimple()
true
if this Geometry
has no interior point of
selfintersection or selftangency. In mathematical formalisms, this means that
every point in the interior of the object must have a metric neighborhood whose
intersection with the object is isomorphic to an nsphere, where n
is the dimension of this Geometry
.
Since most coordinate geometries are represented, either directly or indirectly by functions
from regions in Euclidean space of their topological dimension, the easiest test for
simplicity to require that a function exist that is onetoone and bicontinuous
(continuous in both directions). Such a function is a topological isomorphism. This test
does not work for "closed" objects (that is, objects for which isCycle()
returns
true
).
true
if this object has no interior point of selfintersection or
selftangency.isCycle()
@UML(identifier="isCycle", obligation=MANDATORY, specification=ISO_19107) boolean isCycle()
true
if this Geometry
has an empty boundary after topological
simplification (removal of overlaps between components in nonstructured aggregates, such as
subclasses of Aggregate
). This condition is alternatively
referred to as being "closed" as in a "closed curve." This creates some confusion since there
are two distinct and incompatible definitions for the word "closed". The use of the word cycle
is rarer (generally restricted to the field of algebraic topology), but leads to less confusion.
Essentially, an object is a cycle if it is isomorphic to a geometric object that is the
boundary of a region in some Euclidean space. Thus a curve is a cycle if it is isomorphic
to a circle (has the same start and end point). A surface is a cycle if it isomorphic to the
surface of a sphere, or some torus. A solid, with finite size, in a space of dimension 3 is
never a cycle.true
if this Geometry
has an empty boundary after
topological simplification.isSimple()
@UML(identifier="distance", obligation=MANDATORY, specification=ISO_19107) double distance(Geometry geometry)
Geometry
and another Geometry
.
This distance is defined to be the greatest lower bound of the set of distances between
all pairs of points that include one each from each of the two Geometry
s. A
"distance" value shall be a positive number associated to a distance unit such as meter
or standard foot. If necessary, the second geometric object shall be transformed into
the same coordinate reference system as the first before the distance is calculated.
If the geometric objects overlap, or touch, then their distance apart shall be zero. Some current implementations use a "negative" distance for such cases, but the approach is neither consistent between implementations, nor theoretically viable.
NOTE: The role of the reference system in distance calculations is important. Generally, there are at least three types of distances that may be defined between points (and therefore between geometric objects): map distance, geodesic distance, and terrain distance.
geometry
 The other object.getBoundary()
,
getBuffer(double)
,
CoordinateSystem.getAxis(int)
@UML(identifier="dimension", obligation=MANDATORY, specification=ISO_19107) int getDimension(DirectPosition point)
Geometry
, which shall be less than or
equal to the coordinate dimension. The dimension of
a collection of geometric objects shall be the largest dimension of any of its pieces.
Points are 0dimensional, curves are 1dimensional, surfaces are 2dimensional, and solids
are 3dimensional. Locally, the dimension of a geometric object at a point is the dimension
of a local neighborhood of the point  that is the dimension of any coordinate neighborhood
of the point. Dimension is unambiguously defined only for direct
positions interior to this Geometry
. If the passed direct position is null
, then the operation shall return the largest possible
dimension for any direct position in this Geometry
.point
 The point where to evaluate the dimension, or null
.getCoordinateDimension()
@UML(identifier="coordinateDimension", obligation=MANDATORY, specification=ISO_19107) int getCoordinateDimension()
Geometry
, which must
be the same as the coordinate dimension of the coordinate reference system for this
Geometry
.getDimension(org.opengis.geometry.DirectPosition)
,
getCoordinateReferenceSystem()
@UML(identifier="maximalComplex", obligation=MANDATORY, specification=ISO_19107) Set<? extends Complex> getMaximalComplex()
Geometry
is contained.
As a set of primitives, a complex may be contained as a set in another
larger complex, referred to as a "super complex" of the original.
A complex is maximal if there is no such larger super complex.Geometry
is contained.@UML(identifier="transform", obligation=MANDATORY, specification=ISO_19107) Geometry transform(CoordinateReferenceSystem newCRS) throws TransformException
Geometry
that is the coordinate transformation of this
Geometry
into the passed coordinate reference system within the accuracy
of the transformation.newCRS
 The new coordinate reference system.Geometry
.TransformException
 if the transformation failed.@Extension Geometry transform(CoordinateReferenceSystem newCRS, MathTransform transform) throws TransformException
Geometry
that is the coordinate transformation of this
Geometry
into the passed coordinate reference system, using the
specified transform. It is the user responsability to ensure that the supplied
transform is appropriate for this geometry.newCRS
 The new coordinate reference system.transform
 The transform from the existing coordinate reference system
to the new coordinate reference system.Geometry
.TransformException
 if the transformation failed.@UML(identifier="envelope", obligation=MANDATORY, specification=ISO_19107) Envelope getEnvelope()
Geometry
. This shall be the
coordinate region spanning the minimum and maximum value for each ordinate taken on by
direct positions in this Geometry
. The simplest
representation for an envelope consists of two direct positions,
the first one containing all the minimums for each ordinate, and second one containing all
the maximums. However, there are cases for which these two positions would be outside the
domain of validity of the object's coordinate reference system.getMbRegion()
@UML(identifier="centroid", obligation=MANDATORY, specification=ISO_19107) DirectPosition getCentroid()
Geometry
. The result is not guaranteed
to be on the object. For heterogeneous collections of primitives, the centroid only takes
into account those of the largest dimension. For example, when calculating the centroid of
surfaces, an average is taken weighted by area. Since curves have no area they do not
contribute to the average.getRepresentativePoint()
@UML(identifier="convexHull", obligation=MANDATORY, specification=ISO_19107) Geometry getConvexHull()
Geometry
that represents the convex hull of this Geometry
.
Convexity requires the use of "lines" or "curves of shortest length" and the use of different
coordinate systems may result in different versions of the convex hull of an object. Each
implementation shall decide on an appropriate solution to this ambiguity. For two reasonable
coordinate systems, a convex hull of an object in one will be very closely approximated by
the transformed image of the convex hull of the same object in the other.@UML(identifier="buffer", obligation=MANDATORY, specification=ISO_19107) Geometry getBuffer(double distance)
Geometry
containing all points whose distance from this
Geometry
is less than or equal to the distance passed as a parameter.
The Geometry
returned is in the same reference system as this original
Geometry
. The dimension of the returned Geometry
is normally
the same as the coordinate dimension  a collection of
surfaces in 2D space and a collection of
solids in 3D space, but this may be application
defined.distance
 The distance.Geometry
is less than or equal to the specified distance.getBoundary()
,
#getDistance
,
CoordinateSystem.getAxis(int)
@Extension boolean isMutable()
false
if this geometry is immutable. Immutable geometries are
guarantee to never change their state, neither directly (through a change in this object)
or indirectly (through a change in an other object this geometry depends upon). Immutable
geometries avoid the need for cloning them. More specifically:
If false
, then this geometry is immutable. It is
guarantee that a call to any setFoo(...)
method will throws an
UnmodifiableGeometryException
(that said, immutable geometries
are necessarily unmodifiable. The converse is not true, see next point
below). This geometry will never change its state, and there is no need for
cloning it.
If true
, then this geometry is mutable. Note that
mutable geometry is not synonymous of modifiable
geometry. The nuance lays in whatever the geometry may changes its state
directly (as of user request) or indirectly:
This geometry may be modifiable, in which case invoking
setFoo(...)
methods is legal and will not throws exception.
This geometry may still unmodifiable. User is not allowed to
modify it himself and invoking any setFoo(...)
method will throws
an UnmodifiableGeometryException
. However, the implementation may change
the geometry itself (for example a timevarying geometry).
true
if this geometry is mutable.@Extension Geometry toImmutable()
isMutable()
value of false. Moreover,
as per the contract of isMutable()
, its values will never
change. Any attempts to change the values of the returned object will
result in a UnmodifiableGeometryException
.
Implementors are free to return this
if this object is
already immutable.
Geometry clone() throws CloneNotSupportedException
Special cases:
If this geometry is immutable (isMutable() == false
), then
there is no need for cloning this object. This method may return this
or returns a modifiable copy of this object, at implementation choice.
If a deep copy semantic is not possible at a reasonable cost (for example for some
database backend), then this method throws a CloneNotSupportedException
.
If a deep cloning is possible for all case (i.e. if this method never throws
CloneNotSupportedException
), then the implementation should implements
the Cloneable
interface.
CloneNotSupportedException
 if this object do not support clone. This exception is
never throws if this object implements Cloneable
.Cloneable
,
isMutable()
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