com.vividsolutions.jts.geom
Class Polygon

java.lang.Object
  extended bycom.vividsolutions.jts.geom.Geometry
      extended bycom.vividsolutions.jts.geom.Polygon
All Implemented Interfaces:
java.lang.Cloneable, java.lang.Comparable, java.io.Serializable

public class Polygon
extends Geometry

Represents a linear polygon, which may include holes. The shell and holes of the polygon are represented by LinearRings. In a valid polygon, holes may touch the shell or other holes at a single point. However, no sequence of touching holes may split the polygon into two pieces. The orientation of the rings in the polygon does not matter.

The shell and holes must conform to the assertions specified in the OpenGIS Simple Features Specification for SQL .

Version:
1.7
See Also:
Serialized Form

Field Summary
protected  LinearRing[] holes
          The interior boundaries, if any.
protected  LinearRing shell
          The exterior boundary, or null if this Polygon is empty.
 
Fields inherited from class com.vividsolutions.jts.geom.Geometry
envelope, factory, SRID
 
Constructor Summary
Polygon(LinearRing shell, LinearRing[] holes, GeometryFactory factory)
          Constructs a Polygon with the given exterior boundary and interior boundaries.
Polygon(LinearRing shell, LinearRing[] holes, PrecisionModel precisionModel, int SRID)
          Deprecated. Use GeometryFactory instead
Polygon(LinearRing shell, PrecisionModel precisionModel, int SRID)
          Deprecated. Use GeometryFactory instead
 
Method Summary
 void apply(CoordinateFilter filter)
          Performs an operation with or on this Geometry's coordinates.
 void apply(CoordinateSequenceFilter filter)
          Performs an operation on the coordinates in this Geometry's CoordinateSequences.
 void apply(GeometryComponentFilter filter)
          Performs an operation with or on this Geometry and its component Geometry's.
 void apply(GeometryFilter filter)
          Performs an operation with or on this Geometry and its subelement Geometrys (if any).
 java.lang.Object clone()
          Creates and returns a full copy of this Polygon object.
protected  int compareToSameClass(java.lang.Object o)
          Returns whether this Geometry is greater than, equal to, or less than another Geometry having the same class.
protected  int compareToSameClass(java.lang.Object o, CoordinateSequenceComparator comp)
          Returns whether this Geometry is greater than, equal to, or less than another Geometry of the same class.
protected  Envelope computeEnvelopeInternal()
          Returns the minimum and maximum x and y values in this Geometry , or a null Envelope if this Geometry is empty.
 Geometry convexHull()
          Computes the smallest convex Polygon that contains all the points in the Geometry.
 boolean equalsExact(Geometry other, double tolerance)
          Returns true if the two Geometrys are exactly equal, up to a specified distance tolerance.
 double getArea()
          Returns the area of this Polygon
 Geometry getBoundary()
          Computes the boundary of this geometry
 int getBoundaryDimension()
          Returns the dimension of this Geometrys inherent boundary.
 Coordinate getCoordinate()
          Returns a vertex of this Geometry.
 Coordinate[] getCoordinates()
          Returns this Geometry s vertices.
 int getDimension()
          Returns the dimension of this Geometry.
 LineString getExteriorRing()
           
 java.lang.String getGeometryType()
          Returns the name of this object's com.vivid.jts.geom interface.
 LineString getInteriorRingN(int n)
           
 double getLength()
          Returns the perimeter of this Polygon
 int getNumInteriorRing()
           
 int getNumPoints()
          Returns the count of this Geometrys vertices.
 boolean isEmpty()
          Returns whether or not the set of points in this Geometry is empty.
 boolean isRectangle()
           
 boolean isSimple()
          Tests if a valid polygon is simple.
 void normalize()
          Converts this Geometry to normal form (or canonical form ).
 
Methods inherited from class com.vividsolutions.jts.geom.Geometry
buffer, buffer, buffer, checkNotGeometryCollection, compare, compareTo, compareTo, contains, coveredBy, covers, crosses, difference, disjoint, distance, equal, equals, equalsExact, geometryChanged, geometryChangedAction, getCentroid, getEnvelope, getEnvelopeInternal, getFactory, getGeometryN, getInteriorPoint, getNumGeometries, getPrecisionModel, getSRID, getUserData, hasNonEmptyElements, hasNullElements, intersection, intersects, isEquivalentClass, isValid, isWithinDistance, overlaps, relate, relate, setSRID, setUserData, symDifference, toString, toText, touches, union, within
 
Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Field Detail

shell

protected LinearRing shell
The exterior boundary, or null if this Polygon is empty.


holes

protected LinearRing[] holes
The interior boundaries, if any. This instance var is never null. If there are no holes, the array is of zero length.

Constructor Detail

Polygon

public Polygon(LinearRing shell,
               PrecisionModel precisionModel,
               int SRID)
Deprecated. Use GeometryFactory instead

Constructs a Polygon with the given exterior boundary.

Parameters:
shell - the outer boundary of the new Polygon, or null or an empty LinearRing if the empty geometry is to be created.
precisionModel - the specification of the grid of allowable points for this Polygon
SRID - the ID of the Spatial Reference System used by this Polygon

Polygon

public Polygon(LinearRing shell,
               LinearRing[] holes,
               PrecisionModel precisionModel,
               int SRID)
Deprecated. Use GeometryFactory instead

Constructs a Polygon with the given exterior boundary and interior boundaries.

Parameters:
shell - the outer boundary of the new Polygon, or null or an empty LinearRing if the empty geometry is to be created.
holes - the inner boundaries of the new Polygon , or null or empty LinearRings if the empty geometry is to be created.
precisionModel - the specification of the grid of allowable points for this Polygon
SRID - the ID of the Spatial Reference System used by this Polygon

Polygon

public Polygon(LinearRing shell,
               LinearRing[] holes,
               GeometryFactory factory)
Constructs a Polygon with the given exterior boundary and interior boundaries.

Parameters:
shell - the outer boundary of the new Polygon, or null or an empty LinearRing if the empty geometry is to be created.
holes - the inner boundaries of the new Polygon , or null or empty LinearRings if the empty geometry is to be created.
Method Detail

getCoordinate

public Coordinate getCoordinate()
Description copied from class: Geometry
Returns a vertex of this Geometry.

Specified by:
getCoordinate in class Geometry
Returns:
a Coordinate which is a vertex of this Geometry. Returns null if this Geometry is empty

getCoordinates

public Coordinate[] getCoordinates()
Description copied from class: Geometry
Returns this Geometry s vertices. If you modify the coordinates in this array, be sure to call #geometryChanged afterwards. The Geometrys contained by composite Geometrys must be Geometry's; that is, they must implement getCoordinates.

Specified by:
getCoordinates in class Geometry
Returns:
the vertices of this Geometry

getNumPoints

public int getNumPoints()
Description copied from class: Geometry
Returns the count of this Geometrys vertices. The Geometry s contained by composite Geometrys must be Geometry's; that is, they must implement getNumPoints

Specified by:
getNumPoints in class Geometry
Returns:
the number of vertices in this Geometry

getDimension

public int getDimension()
Description copied from class: Geometry
Returns the dimension of this Geometry.

Specified by:
getDimension in class Geometry
Returns:
the dimension of the class implementing this interface, whether or not this object is the empty geometry

getBoundaryDimension

public int getBoundaryDimension()
Description copied from class: Geometry
Returns the dimension of this Geometrys inherent boundary.

Specified by:
getBoundaryDimension in class Geometry
Returns:
the dimension of the boundary of the class implementing this interface, whether or not this object is the empty geometry. Returns Dimension.FALSE if the boundary is the empty geometry.

isEmpty

public boolean isEmpty()
Description copied from class: Geometry
Returns whether or not the set of points in this Geometry is empty.

Specified by:
isEmpty in class Geometry
Returns:
true if this Geometry equals the empty geometry

isSimple

public boolean isSimple()
Tests if a valid polygon is simple. This method always returns true, since a valid polygon is always simple

Overrides:
isSimple in class Geometry
Returns:
true
See Also:
Geometry.isValid()

isRectangle

public boolean isRectangle()
Overrides:
isRectangle in class Geometry

getExteriorRing

public LineString getExteriorRing()

getNumInteriorRing

public int getNumInteriorRing()

getInteriorRingN

public LineString getInteriorRingN(int n)

getGeometryType

public java.lang.String getGeometryType()
Description copied from class: Geometry
Returns the name of this object's com.vivid.jts.geom interface.

Specified by:
getGeometryType in class Geometry
Returns:
the name of this Geometrys most specific com.vividsolutions.jts.geom interface

getArea

public double getArea()
Returns the area of this Polygon

Overrides:
getArea in class Geometry
Returns:
the area of the polygon

getLength

public double getLength()
Returns the perimeter of this Polygon

Overrides:
getLength in class Geometry
Returns:
the perimeter of the polygon

getBoundary

public Geometry getBoundary()
Computes the boundary of this geometry

Specified by:
getBoundary in class Geometry
Returns:
a lineal geometry (which may be empty)
See Also:
Geometry.getBoundary()

computeEnvelopeInternal

protected Envelope computeEnvelopeInternal()
Description copied from class: Geometry
Returns the minimum and maximum x and y values in this Geometry , or a null Envelope if this Geometry is empty. Unlike getEnvelopeInternal, this method calculates the Envelope each time it is called; getEnvelopeInternal caches the result of this method.

Specified by:
computeEnvelopeInternal in class Geometry
Returns:
this Geometrys bounding box; if the Geometry is empty, Envelope#isNull will return true

equalsExact

public boolean equalsExact(Geometry other,
                           double tolerance)
Description copied from class: Geometry
Returns true if the two Geometrys are exactly equal, up to a specified distance tolerance. Two Geometries are exactly equal within a distance tolerance if and only if: If this and the other Geometrys are composites and any children are not Geometrys, returns false.

Specified by:
equalsExact in class Geometry
Parameters:
other - the Geometry with which to compare this Geometry
Returns:
true if this and the other Geometry are of the same class and have equal internal data.

apply

public void apply(CoordinateFilter filter)
Description copied from class: Geometry
Performs an operation with or on this Geometry's coordinates. If this method modifies any coordinate values, #geometryChanged() must be called to update the geometry state. Note that you cannot use this method to modify this Geometry if its underlying CoordinateSequence's #get method returns a copy of the Coordinate, rather than the actual Coordinate stored (if it even stores Coordinates at all).

Specified by:
apply in class Geometry
Parameters:
filter - the filter to apply to this Geometry's coordinates

apply

public void apply(CoordinateSequenceFilter filter)
Description copied from class: Geometry
Performs an operation on the coordinates in this Geometry's CoordinateSequences. If this method modifies any coordinate values, #geometryChanged() must be called to update the geometry state.

Specified by:
apply in class Geometry
Parameters:
filter - the filter to apply

apply

public void apply(GeometryFilter filter)
Description copied from class: Geometry
Performs an operation with or on this Geometry and its subelement Geometrys (if any). Only GeometryCollections and subclasses have subelement Geometry's.

Specified by:
apply in class Geometry
Parameters:
filter - the filter to apply to this Geometry (and its children, if it is a GeometryCollection).

apply

public void apply(GeometryComponentFilter filter)
Description copied from class: Geometry
Performs an operation with or on this Geometry and its component Geometry's. Only GeometryCollections and Polygons have component Geometry's; for Polygons they are the LinearRings of the shell and holes.

Specified by:
apply in class Geometry
Parameters:
filter - the filter to apply to this Geometry.

clone

public java.lang.Object clone()
Creates and returns a full copy of this Polygon object. (including all coordinates contained by it).

Overrides:
clone in class Geometry
Returns:
a clone of this instance

convexHull

public Geometry convexHull()
Description copied from class: Geometry
Computes the smallest convex Polygon that contains all the points in the Geometry. This obviously applies only to Geometry s which contain 3 or more points; the results for degenerate cases are specified as follows:
Number of Points in argument Geometry Geometry class of result
0 empty GeometryCollection
1 Point
2 LineString
3 or more Polygon

Overrides:
convexHull in class Geometry
Returns:
the minimum-area convex polygon containing this Geometry' s points

normalize

public void normalize()
Description copied from class: Geometry
Converts this Geometry to normal form (or canonical form ). Normal form is a unique representation for Geometry s. It can be used to test whether two Geometrys are equal in a way that is independent of the ordering of the coordinates within them. Normal form equality is a stronger condition than topological equality, but weaker than pointwise equality. The definitions for normal form use the standard lexicographical ordering for coordinates. "Sorted in order of coordinates" means the obvious extension of this ordering to sequences of coordinates.

Specified by:
normalize in class Geometry

compareToSameClass

protected int compareToSameClass(java.lang.Object o)
Description copied from class: Geometry
Returns whether this Geometry is greater than, equal to, or less than another Geometry having the same class.

Specified by:
compareToSameClass in class Geometry
Parameters:
o - a Geometry having the same class as this Geometry
Returns:
a positive number, 0, or a negative number, depending on whether this object is greater than, equal to, or less than o, as defined in "Normal Form For Geometry" in the JTS Technical Specifications

compareToSameClass

protected int compareToSameClass(java.lang.Object o,
                                 CoordinateSequenceComparator comp)
Description copied from class: Geometry
Returns whether this Geometry is greater than, equal to, or less than another Geometry of the same class. using the given CoordinateSequenceComparator.

Specified by:
compareToSameClass in class Geometry
Parameters:
o - a Geometry having the same class as this Geometry
comp - a CoordinateSequenceComparator
Returns:
a positive number, 0, or a negative number, depending on whether this object is greater than, equal to, or less than o, as defined in "Normal Form For Geometry" in the JTS Technical Specifications