Package org.locationtech.jts.geom

Class LineString

  • All Implemented Interfaces:
    Serializable, Cloneable, Comparable, Lineal
    Direct Known Subclasses:
    LinearRing
    public class LineString
extends Geometry
implements Lineal
    Models an OGC-style LineString. A LineString consists of a sequence of two or more vertices, along with all points along the linearly-interpolated curves (line segments) between each pair of consecutive vertices. Consecutive vertices may be equal. The line segments in the line may intersect each other (in other words, the linestring may "curl back" in itself and self-intersect. Linestrings with exactly two identical points are invalid.

    A linestring must have either 0 or 2 or more points. If these conditions are not met, the constructors throw an IllegalArgumentException

    Version:
    1.7
    See Also:
    Serialized Form

    • Constructor Detail

      • LineString

        public LineString​(Coordinate[] points,
                  PrecisionModel precisionModel,
                  int SRID)
        Deprecated.
        Use GeometryFactory instead

      • LineString

        public LineString​(CoordinateSequence points,
                  GeometryFactory factory)
        Constructs a LineString with the given points.
        Parameters:
        points - the points of the linestring, or null to create the empty geometry.
        Throws:
        IllegalArgumentException - if too few points are provided

    • Method Detail

      • getCoordinateN

        public Coordinate getCoordinateN​(int n)

      • getCoordinate

        public Coordinate getCoordinate()
        Description copied from class: Geometry
        Returns a vertex of this Geometry (usually, but not necessarily, the first one). The returned coordinate should not be assumed to be an actual Coordinate object used in the internal representation.
        Specified by:
        getCoordinate in class Geometry
        Returns:
        a Coordinate which is a vertex of this Geometry.

      • getDimension

        public int getDimension()
        Description copied from class: Geometry
        Returns the dimension of this geometry. The dimension of a geometry is is the topological dimension of its embedding in the 2-D Euclidean plane. In the JTS spatial model, dimension values are in the set {0,1,2}.

        Note that this is a different concept to the dimension of the vertex Coordinates. The geometry dimension can never be greater than the coordinate dimension. For example, a 0-dimensional geometry (e.g. a Point) may have a coordinate dimension of 3 (X,Y,Z).

        Specified by:
        getDimension in class Geometry
        Returns:
        the topological dimension of this 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
        Tests whether the set of points covered by this Geometry is empty.
        Specified by:
        isEmpty in class Geometry
        Returns:
        true if this Geometry does not cover any points

      • 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

      • getPointN

        public Point getPointN​(int n)

      • getStartPoint

        public Point getStartPoint()

      • getEndPoint

        public Point getEndPoint()

      • isClosed

        public boolean isClosed()

      • isRing

        public boolean isRing()

      • getGeometryType

        public String getGeometryType()
        Description copied from class: Geometry
        Returns the name of this Geometry's actual class.
        Specified by:
        getGeometryType in class Geometry
        Returns:
        the name of this Geometrys actual class

      • getLength

        public double getLength()
        Returns the length of this LineString
        Overrides:
        getLength in class Geometry
        Returns:
        the length of the linestring

      • getBoundary

        public Geometry getBoundary()
        Gets the boundary of this geometry. The boundary of a lineal geometry is always a zero-dimensional geometry (which may be empty).
        Specified by:
        getBoundary in class Geometry
        Returns:
        the boundary geometry
        See Also:
        Geometry.getBoundary()

      • reverse

        public Geometry reverse()
        Creates a LineString whose coordinates are in the reverse order of this objects
        Specified by:
        reverse in class Geometry
        Returns:
        a LineString with coordinates in the reverse order

      • isCoordinate

        public boolean isCoordinate​(Coordinate pt)
        Returns true if the given point is a vertex of this LineString.
        Parameters:
        pt - the Coordinate to check
        Returns:
        true if pt is one of this LineString 's vertices

      • 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:
        • they have the same structure
        • they have the same values for their vertices, within the given tolerance distance, in exactly the same order.
        This method does not test the values of the GeometryFactory, the SRID, or the userData fields.

        To properly test equality between different geometries, it is usually necessary to Geometry.normalize() them first.

        Specified by:
        equalsExact in class Geometry
        Parameters:
        other - the Geometry with which to compare this Geometry
        tolerance - distance at or below which two Coordinates are considered equal
        Returns:
        true if this and the other Geometry have identical structure and point values, up to the distance tolerance.
        See Also:
        Geometry.equalsExact(Geometry), Geometry.normalize(), Geometry.norm()

      • 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, Geometry.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 Coordinate objects at all).
        Specified by:
        apply in class Geometry
        Parameters:
        filter - the filter to apply to this Geometry's coordinates

      • 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 Object clone()
        Deprecated.
        Creates and returns a full copy of this LineString object. (including all coordinates contained by it).
        Overrides:
        clone in class Geometry
        Returns:
        a clone of this instance

      • copyInternal

        protected LineString copyInternal()
        Description copied from class: Geometry
        An internal method to copy subclass-specific geometry data.
        Specified by:
        copyInternal in class Geometry
        Returns:
        a copy of the target geometry object.

      • normalize

        public void normalize()
        Normalizes a LineString. A normalized linestring has the first point which is not equal to it's reflected point less than the reflected point.
        Specified by:
        normalize in class Geometry

      • isEquivalentClass

        protected boolean isEquivalentClass​(Geometry other)
        Description copied from class: Geometry
        Returns whether the two Geometrys are equal, from the point of view of the equalsExact method. Called by equalsExact . In general, two Geometry classes are considered to be "equivalent" only if they are the same class. An exception is LineString , which is considered to be equivalent to its subclasses.
        Overrides:
        isEquivalentClass in class Geometry
        Parameters:
        other - the Geometry with which to compare this Geometry for equality
        Returns:
        true if the classes of the two Geometry s are considered to be equal by the equalsExact method.

      • compareToSameClass

        protected int compareToSameClass​(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​(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