com.vividsolutions.jts.geom
Class Coordinate

java.lang.Object
  com.vividsolutions.jts.geom.Coordinate

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.lang.Comparable

public class Coordinate
extends java.lang.Object
implements java.lang.Comparable, java.lang.Cloneable, java.io.Serializable

A lightweight class used to store coordinates on the 2-dimensional Cartesian plane. It is distinct from Point, which is a subclass of Geometry. Unlike objects of type Point (which contain additional information such as an envelope, a precision model, and spatial reference system information), a Coordinate only contains ordinate values and accessor methods.

Coordinates are two-dimensional points, with an additional Z-ordinate. JTS does not support any operations on the Z-ordinate except the basic accessor functions. If an Z-ordinate value is not specified or not defined, constructed coordinates have a Z-ordinate of NaN (which is also the value of NULL_ORDINATE). The standard comparison functions ignore the Z-ordinate.

Version:

1.7

See Also:

Serialized Form

Nested Class Summary

static class

Coordinate.DimensionalComparator Compares two Coordinates, allowing for either a 2-dimensional or 3-dimensional comparison, and handling NaN values correctly.

Field Summary

static double	NULL_ORDINATE The value used to indicate a null or missing ordinate value.
double	x The x-coordinate.
double	y The y-coordinate.
double	z The z-coordinate.

Constructor Summary

Coordinate()
Constructs a Coordinate at (0,0,NaN).

Coordinate(Coordinate c)
Constructs a Coordinate having the same (x,y,z) values as other.

Coordinate(double x, double y)
Constructs a Coordinate at (x,y,NaN).

Coordinate(double x, double y, double z)
Constructs a Coordinate at (x,y,z).

Method Summary

java.lang.Object	clone()
int	compareTo(java.lang.Object o) Compares this Coordinate with the specified Coordinate for order.
double	distance(Coordinate p) Computes the 2-dimensional Euclidean distance to another location.
boolean	equals(java.lang.Object other) Returns true if other has the same values for the x and y ordinates.
boolean	equals2D(Coordinate other) Returns whether the planar projections of the two Coordinates are equal.
boolean	equals3D(Coordinate other) Returns true if other has the same values for x, y and z.
int	hashCode() Gets a hashcode for this coordinate.
static int	hashCode(double x) Computes a hash code for a double value, using the algorithm from Joshua Bloch's book Effective Java"
void	setCoordinate(Coordinate other) Sets this Coordinates (x,y,z) values to that of other.
java.lang.String	toString() Returns a String of the form (x,y,z) .

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

NULL_ORDINATE

public static final double NULL_ORDINATE

The value used to indicate a null or missing ordinate value. In particular, used for the value of ordinates for dimensions greater than the defined dimension of a coordinate.

See Also:

Constant Field Values

x

public double x

The x-coordinate.

y

public double y

The y-coordinate.

z

public double z

The z-coordinate.

Constructor Detail

Coordinate

public Coordinate(double x,
                  double y,
                  double z)

Constructs a Coordinate at (x,y,z).

Parameters:

x - the x-value

y - the y-value

z - the z-value

Coordinate

public Coordinate()

Constructs a Coordinate at (0,0,NaN).

Coordinate

public Coordinate(Coordinate c)

Constructs a Coordinate having the same (x,y,z) values as other.

Parameters:

c - the Coordinate to copy.

Coordinate

public Coordinate(double x,
                  double y)

Constructs a Coordinate at (x,y,NaN).

Parameters:

x - the x-value

y - the y-value

Method Detail

setCoordinate

public void setCoordinate(Coordinate other)

Sets this Coordinates (x,y,z) values to that of other.

Parameters:

other - the Coordinate to copy

equals2D

public boolean equals2D(Coordinate other)

Returns whether the planar projections of the two Coordinates are equal.

Parameters:

other - a Coordinate with which to do the 2D comparison.

Returns:

true if the x- and y-coordinates are equal; the z-coordinates do not have to be equal.

equals

public boolean equals(java.lang.Object other)

Returns true if other has the same values for the x and y ordinates. Since Coordinates are 2.5D, this routine ignores the z value when making the comparison.

Overrides:

equals in class java.lang.Object

Parameters:

other - a Coordinate with which to do the comparison.

Returns:

true if other is a Coordinate with the same values for the x and y ordinates.

compareTo

public int compareTo(java.lang.Object o)

Compares this Coordinate with the specified Coordinate for order. This method ignores the z value when making the comparison. Returns:

• -1 : this.x < other.x || ((this.x == other.x) && (this.y < other.y))
• 0 : this.x == other.x && this.y = other.y
• 1 : this.x > other.x || ((this.x == other.x) && (this.y > other.y))

Note: This method assumes that ordinate values are valid numbers. NaN values are not handled correctly.

Specified by:

compareTo in interface java.lang.Comparable

Parameters:

o - the Coordinate with which this Coordinate is being compared

Returns:

-1, zero, or 1 as this Coordinate is less than, equal to, or greater than the specified Coordinate

equals3D

public boolean equals3D(Coordinate other)

Returns true if other has the same values for x, y and z.

Parameters:

other - a Coordinate with which to do the 3D comparison.

Returns:

true if other is a Coordinate with the same values for x, y and z.

toString

public java.lang.String toString()

Returns a String of the form (x,y,z) .

Overrides:

toString in class java.lang.Object

Returns:

a String of the form (x,y,z)

clone

public java.lang.Object clone()

Overrides:

clone in class java.lang.Object

distance

public double distance(Coordinate p)

Computes the 2-dimensional Euclidean distance to another location. The Z-ordinate is ignored.

Parameters:

p - a point

Returns:

the 2-dimensional Euclidean distance between the locations

hashCode

public int hashCode()

Gets a hashcode for this coordinate.

Overrides:

hashCode in class java.lang.Object

Returns:

a hashcode for this coordinate

hashCode

public static int hashCode(double x)

Computes a hash code for a double value, using the algorithm from Joshua Bloch's book Effective Java"

Returns:

a hashcode for the double value