Represents a location along a LineString or MultiLineString. The referenced geometry is not maintained within this location, but must be provided for operations which require it. Various methods are provided to manipulate the location value and query the geometry it references.

public LinearLocation()

Creates a location referring to the start of a linear geometry

public LinearLocation(int segmentIndex, double segmentFraction)

public LinearLocation(int componentIndex, int segmentIndex, double segmentFraction)

public LinearLocation(LinearLocation loc)

Creates a new location equal to a given one.

Parameters:: loc - loc a LinearLocation

public static LinearLocation getEndLocation(Geometry linear)

Gets a location which refers to the end of a linear Geometry.

Parameters:: linear - linear the linear geometry

Returns:: a new LinearLocation

public static Coordinate pointAlongSegmentByFraction(Coordinate p0, Coordinate p1, double frac)

Computes the Coordinate of a point a given fraction along the line segment (p0, p1). If the fraction is greater than 1.0 the last point of the segment is returned. If the fraction is less than or equal to 0.0 the first point of the segment is returned. The Z ordinate is interpolated from the Z-ordinates of the given points, if they are specified.

Parameters:: p0 - p0 the first point of the line segment; p1 - p1 the last point of the line segment; frac - frac the length to the desired point

Returns:: the Coordinate of the desired point

public void clamp(Geometry linear)

Ensures the indexes are valid for a given linear Geometry.

Parameters:: linear - linear a linear geometry

public void snapToVertex(Geometry linearGeom, double minDistance)

Snaps the value of this location to the nearest vertex on the given linear Geometry, if the vertex is closer than minDistance.

Parameters:: linearGeom - linearGeom a linear geometry; minDistance - minDistance the minimum allowable distance to a vertex

public double getSegmentLength(Geometry linearGeom)

Gets the length of the segment in the given Geometry containing this location.

Parameters:: linearGeom - linearGeom a linear geometry

Returns:: the length of the segment

public void setToEnd(Geometry linear)

Sets the value of this location to refer to the end of a linear geometry.

Parameters:: linear - linear the linear geometry to use to set the end

public int getComponentIndex()

Gets the component index for this location.

Returns:: the component index

public int getSegmentIndex()

Gets the segment index for this location

Returns:: the segment index

public double getSegmentFraction()

Gets the segment fraction for this location

Returns:: the segment fraction

public boolean isVertex()

Tests whether this location refers to a vertex

Returns:: true if the location is a vertex

public Coordinate getCoordinate(Geometry linearGeom)

Gets the Coordinate along the given linear Geometry which is referenced by this location.

Parameters:: linearGeom - linearGeom the linear geometry referenced by this location

Returns:: the Coordinate at the location

public LineSegment getSegment(Geometry linearGeom)

Gets a LineSegment representing the segment of the given linear Geometry which contains this location.

Parameters:: linearGeom - linearGeom a linear geometry

Returns:: the LineSegment containing the location

public boolean isValid(Geometry linearGeom)

Tests whether this location refers to a valid location on the given linear Geometry.

Parameters:: linearGeom - linearGeom a linear geometry

Returns:: true if this location is valid

public int compareTo(Object o)

Compares this object with the specified object for order.

Parameters:: o - o the LineStringLocation with which this Coordinate is being compared

Returns:: a negative integer, zero, or a positive integer as this LineStringLocation is less than, equal to, or greater than the specified LineStringLocation

public int compareLocationValues(int componentIndex1, int segmentIndex1, double segmentFraction1)

Compares this object with the specified index values for order.

Parameters:: componentIndex1 - componentIndex1 a component index; segmentIndex1 - segmentIndex1 a segment index; segmentFraction1 - segmentFraction1 a segment fraction

Returns:: a negative integer, zero, or a positive integer as this LineStringLocation is less than, equal to, or greater than the specified locationValues

public static int compareLocationValues(int componentIndex0, int segmentIndex0, double segmentFraction0, int componentIndex1, int segmentIndex1, double segmentFraction1)

Compares two sets of location values for order.

Parameters:: componentIndex0 - componentIndex0 a component index; segmentIndex0 - segmentIndex0 a segment index; segmentFraction0 - segmentFraction0 a segment fraction; componentIndex1 - componentIndex1 another component index; segmentIndex1 - segmentIndex1 another segment index; segmentFraction1 - segmentFraction1 another segment fraction

Returns:: a negative integer, zero, or a positive integer as the first set of location values is less than, equal to, or greater than the second set of locationValues

public boolean isOnSameSegment(LinearLocation loc)

Tests whether two locations are on the same segment in the parent Geometry.

Parameters:: loc - loc a location on the same geometry

Returns:: true if the locations are on the same segment of the parent geometry

public boolean isEndpoint(Geometry linearGeom)

Tests whether this location is an endpoint of the linear component it refers to.

Parameters:: linearGeom - linearGeom the linear geometry referenced by this location

Returns:: true if the location is a component endpoint

public LinearLocation toLowest(Geometry linearGeom)

Converts a linear location to the lowest equivalent location index. The lowest index has the lowest possible component and segment indices.

Specifically:

if the location point is an endpoint, a location value is returned as (nseg-1, 1.0)
if the location point is ambiguous (i.e. an endpoint and a startpoint), the lowest endpoint location is returned

If the location index is already the lowest possible value, the original location is returned.

Parameters:: linearGeom - linearGeom the linear geometry referenced by this location

Returns:: the lowest equivalent location

public Object clone()

Copies this location

Returns:: a copy of this location

public LinearLocation copy()

Copies this location

Returns:: a copy of this location

public String toString()