public abstract class Line2D extends Objectimplements Shape , Cloneable
Line2D represents a line segment in
(x,y) coordinate space. This class, like all of the Java 2D API, uses a default coordinate system called
user space in which the y-axis values increase downward and x-axis values increase to the right. For more information on the user space coordinate system, see the
Coordinate Systems section of the Java 2D Programmer's Guide.
This class is only the abstract superclass for all objects that store a 2D line segment. The actual storage representation of the coordinates is left to the subclass.
| Modifier and Type | Class and Description |
|---|---|
static class |
Line2D
A line segment specified with double coordinates.
|
static class |
Line2D
A line segment specified with float coordinates.
|
| Modifier | Constructor and Description |
|---|---|
protected |
Line2D()
This is an abstract class that cannot be instantiated directly.
|
| Modifier and Type | Method and Description |
|---|---|
Object |
clone()
Creates a new object of the same class as this object.
|
boolean |
contains(double x, double y)
Tests if a specified coordinate is inside the boundary of this
Line2D.
|
boolean |
contains(double x, double y, double w, double h)
Tests if the interior of this
Line2D entirely contains the specified set of rectangular coordinates.
|
boolean |
contains(Point2D
Tests if a given
Point2D is inside the boundary of this
Line2D.
|
boolean |
contains(Rectangle2D
Tests if the interior of this
Line2D entirely contains the specified
Rectangle2D.
|
Rectangle |
getBounds()
Returns an integer
Rectangle that completely encloses the
Shape.
|
abstract Point2D |
getP1()
Returns the start
Point2D of this
Line2D.
|
abstract Point2D |
getP2()
Returns the end
Point2D of this
Line2D.
|
PathIterator |
getPathIterator(AffineTransform
Returns an iteration object that defines the boundary of this
Line2D.
|
PathIterator |
getPathIterator(AffineTransform
Returns an iteration object that defines the boundary of this flattened
Line2D.
|
abstract double |
getX1()
Returns the X coordinate of the start point in double precision.
|
abstract double |
getX2()
Returns the X coordinate of the end point in double precision.
|
abstract double |
getY1()
Returns the Y coordinate of the start point in double precision.
|
abstract double |
getY2()
Returns the Y coordinate of the end point in double precision.
|
boolean |
intersects(double x, double y, double w, double h)
Tests if the interior of the
Shape intersects the interior of a specified rectangular area.
|
boolean |
intersects(Rectangle2D
Tests if the interior of the
Shape intersects the interior of a specified
Rectangle2D.
|
boolean |
intersectsLine(double x1, double y1, double x2, double y2)
Tests if the line segment from
(x1,y1) to
(x2,y2) intersects this line segment.
|
boolean |
intersectsLine(Line2D
Tests if the specified line segment intersects this line segment.
|
static boolean |
linesIntersect(double x1, double y1, double x2, double y2, double x3, double y3, double x4, double y4)
Tests if the line segment from
(x1,y1) to
(x2,y2) intersects the line segment from
(x3,y3) to
(x4,y4).
|
double |
ptLineDist(double px, double py)
Returns the distance from a point to this line.
|
static double |
ptLineDist(double x1, double y1, double x2, double y2, double px, double py)
Returns the distance from a point to a line.
|
double |
ptLineDist(Point2D
Returns the distance from a
Point2D to this line.
|
double |
ptLineDistSq(double px, double py)
Returns the square of the distance from a point to this line.
|
static double |
ptLineDistSq(double x1, double y1, double x2, double y2, double px, double py)
Returns the square of the distance from a point to a line.
|
double |
ptLineDistSq(Point2D
Returns the square of the distance from a specified
Point2D to this line.
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double |
ptSegDist(double px, double py)
Returns the distance from a point to this line segment.
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static double |
ptSegDist(double x1, double y1, double x2, double y2, double px, double py)
Returns the distance from a point to a line segment.
|
double |
ptSegDist(Point2D
Returns the distance from a
Point2D to this line segment.
|
double |
ptSegDistSq(double px, double py)
Returns the square of the distance from a point to this line segment.
|
static double |
ptSegDistSq(double x1, double y1, double x2, double y2, double px, double py)
Returns the square of the distance from a point to a line segment.
|
double |
ptSegDistSq(Point2D
Returns the square of the distance from a
Point2D to this line segment.
|
int |
relativeCCW(double px, double py)
Returns an indicator of where the specified point
(px,py) lies with respect to this line segment.
|
static int |
relativeCCW(double x1, double y1, double x2, double y2, double px, double py)
Returns an indicator of where the specified point
(px,py) lies with respect to the line segment from
(x1,y1) to
(x2,y2).
|
int |
relativeCCW(Point2D
Returns an indicator of where the specified
Point2D lies with respect to this line segment.
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abstract void |
setLine(double x1, double y1, double x2, double y2)
Sets the location of the end points of this
Line2D to the specified double coordinates.
|
void |
setLine(Line2D
Sets the location of the end points of this
Line2D to the same as those end points of the specified
Line2D.
|
void |
setLine(Point2D
Sets the location of the end points of this
Line2D to the specified
Point2D coordinates.
|
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, waitgetBounds2Dprotected Line2D()
Line2D.Float,
Line2D.Double
public abstract double getX1()
Line2D object.
public abstract double getY1()
Line2D object.
public abstract Point2DgetP1()
Point2D of this
Line2D.
Point2D of this
Line2D.
public abstract double getX2()
Line2D object.
public abstract double getY2()
Line2D object.
public abstract Point2DgetP2()
Point2D of this
Line2D.
Point2D of this
Line2D.
public abstract void setLine(double x1,
double y1,
double x2,
double y2)
Line2D to the specified double coordinates.
x1 - the X coordinate of the start point
y1 - the Y coordinate of the start point
x2 - the X coordinate of the end point
y2 - the Y coordinate of the end point
public void setLine(Point2Dp1, Point2D p2)
Line2D to the specified
Point2D coordinates.
p1 - the start
Point2D of the line segment
p2 - the end
Point2D of the line segment
public void setLine(Line2Dl)
Line2D to the same as those end points of the specified
Line2D.
l - the specified
Line2D
public static int relativeCCW(double x1,
double y1,
double x2,
double y2,
double px,
double py)
(px,py) lies with respect to the line segment from
(x1,y1) to
(x2,y2). The return value can be either 1, -1, or 0 and indicates in which direction the specified line must pivot around its first end point,
(x1,y1), in order to point at the specified point
(px,py).
A return value of 1 indicates that the line segment must turn in the direction that takes the positive X axis towards the negative Y axis. In the default coordinate system used by Java 2D, this direction is counterclockwise.
A return value of -1 indicates that the line segment must turn in the direction that takes the positive X axis towards the positive Y axis. In the default coordinate system, this direction is clockwise.
A return value of 0 indicates that the point lies exactly on the line segment. Note that an indicator value of 0 is rare and not useful for determining collinearity because of floating point rounding issues.
If the point is colinear with the line segment, but not between the end points, then the value will be -1 if the point lies "beyond (x1,y1)" or 1 if the point lies "beyond (x2,y2)".
x1 - the X coordinate of the start point of the specified line segment
y1 - the Y coordinate of the start point of the specified line segment
x2 - the X coordinate of the end point of the specified line segment
y2 - the Y coordinate of the end point of the specified line segment
px - the X coordinate of the specified point to be compared with the specified line segment
py - the Y coordinate of the specified point to be compared with the specified line segment
public int relativeCCW(double px,
double py)
(px,py) lies with respect to this line segment. See the method comments of
relativeCCW(double, double, double, double, double, double) to interpret the return value.
px - the X coordinate of the specified point to be compared with this
Line2D
py - the Y coordinate of the specified point to be compared with this
Line2D
Line2D
relativeCCW(double, double, double, double, double, double)
public int relativeCCW(Point2Dp)
Point2D lies with respect to this line segment. See the method comments of
relativeCCW(double, double, double, double, double, double) to interpret the return value.
p - the specified
Point2D to be compared with this
Line2D
Point2D with respect to this
Line2D
relativeCCW(double, double, double, double, double, double)
public static boolean linesIntersect(double x1,
double y1,
double x2,
double y2,
double x3,
double y3,
double x4,
double y4)
(x1,y1) to
(x2,y2) intersects the line segment from
(x3,y3) to
(x4,y4).
x1 - the X coordinate of the start point of the first specified line segment
y1 - the Y coordinate of the start point of the first specified line segment
x2 - the X coordinate of the end point of the first specified line segment
y2 - the Y coordinate of the end point of the first specified line segment
x3 - the X coordinate of the start point of the second specified line segment
y3 - the Y coordinate of the start point of the second specified line segment
x4 - the X coordinate of the end point of the second specified line segment
y4 - the Y coordinate of the end point of the second specified line segment
true if the first specified line segment and the second specified line segment intersect each other;
false otherwise.
public boolean intersectsLine(double x1,
double y1,
double x2,
double y2)
(x1,y1) to
(x2,y2) intersects this line segment.
x1 - the X coordinate of the start point of the specified line segment
y1 - the Y coordinate of the start point of the specified line segment
x2 - the X coordinate of the end point of the specified line segment
y2 - the Y coordinate of the end point of the specified line segment
<true> if this line segment and the specified line segment intersect each other;
false otherwise.
public boolean intersectsLine(Line2Dl)
l - the specified
Line2D
true if this line segment and the specified line segment intersect each other;
false otherwise.
public static double ptSegDistSq(double x1,
double y1,
double x2,
double y2,
double px,
double py)
x1 - the X coordinate of the start point of the specified line segment
y1 - the Y coordinate of the start point of the specified line segment
x2 - the X coordinate of the end point of the specified line segment
y2 - the Y coordinate of the end point of the specified line segment
px - the X coordinate of the specified point being measured against the specified line segment
py - the Y coordinate of the specified point being measured against the specified line segment
ptLineDistSq(double, double, double, double, double, double)
public static double ptSegDist(double x1,
double y1,
double x2,
double y2,
double px,
double py)
x1 - the X coordinate of the start point of the specified line segment
y1 - the Y coordinate of the start point of the specified line segment
x2 - the X coordinate of the end point of the specified line segment
y2 - the Y coordinate of the end point of the specified line segment
px - the X coordinate of the specified point being measured against the specified line segment
py - the Y coordinate of the specified point being measured against the specified line segment
ptLineDist(double, double, double, double, double, double)
public double ptSegDistSq(double px,
double py)
px - the X coordinate of the specified point being measured against this line segment
py - the Y coordinate of the specified point being measured against this line segment
ptLineDistSq(double, double)
public double ptSegDistSq(Point2Dpt)
Point2D to this line segment. The distance measured is the distance between the specified point and the closest point between the current line's end points. If the specified point intersects the line segment in between the end points, this method returns 0.0.
pt - the specified
Point2D being measured against this line segment.
Point2D to the current line segment.
ptLineDistSq(Point2D)
public double ptSegDist(double px,
double py)
px - the X coordinate of the specified point being measured against this line segment
py - the Y coordinate of the specified point being measured against this line segment
ptLineDist(double, double)
public double ptSegDist(Point2Dpt)
Point2D to this line segment. The distance measured is the distance between the specified point and the closest point between the current line's end points. If the specified point intersects the line segment in between the end points, this method returns 0.0.
pt - the specified
Point2D being measured against this line segment
Point2D to the current line segment.
ptLineDist(Point2D)
public static double ptLineDistSq(double x1,
double y1,
double x2,
double y2,
double px,
double py)
x1 - the X coordinate of the start point of the specified line
y1 - the Y coordinate of the start point of the specified line
x2 - the X coordinate of the end point of the specified line
y2 - the Y coordinate of the end point of the specified line
px - the X coordinate of the specified point being measured against the specified line
py - the Y coordinate of the specified point being measured against the specified line
ptSegDistSq(double, double, double, double, double, double)
public static double ptLineDist(double x1,
double y1,
double x2,
double y2,
double px,
double py)
x1 - the X coordinate of the start point of the specified line
y1 - the Y coordinate of the start point of the specified line
x2 - the X coordinate of the end point of the specified line
y2 - the Y coordinate of the end point of the specified line
px - the X coordinate of the specified point being measured against the specified line
py - the Y coordinate of the specified point being measured against the specified line
ptSegDist(double, double, double, double, double, double)
public double ptLineDistSq(double px,
double py)
Line2D. If the specified point intersects the line, this method returns 0.0.
px - the X coordinate of the specified point being measured against this line
py - the Y coordinate of the specified point being measured against this line
ptSegDistSq(double, double)
public double ptLineDistSq(Point2Dpt)
Point2D to this line. The distance measured is the distance between the specified point and the closest point on the infinitely-extended line defined by this
Line2D. If the specified point intersects the line, this method returns 0.0.
pt - the specified
Point2D being measured against this line
Point2D to the current line.
ptSegDistSq(Point2D)
public double ptLineDist(double px,
double py)
Line2D. If the specified point intersects the line, this method returns 0.0.
px - the X coordinate of the specified point being measured against this line
py - the Y coordinate of the specified point being measured against this line
ptSegDist(double, double)
public double ptLineDist(Point2Dpt)
Point2D to this line. The distance measured is the distance between the specified point and the closest point on the infinitely-extended line defined by this
Line2D. If the specified point intersects the line, this method returns 0.0.
pt - the specified
Point2D being measured
Point2D to the current line.
ptSegDist(Point2D)
public boolean contains(double x,
double y)
Line2D. This method is required to implement the
Shape interface, but in the case of
Line2D objects it always returns
false since a line contains no area.
public boolean contains(Point2Dp)
Point2D is inside the boundary of this
Line2D. This method is required to implement the
Shape interface, but in the case of
Line2D objects it always returns
false since a line contains no area.
public boolean intersects(double x,
double y,
double w,
double h)
Shape intersects the interior of a specified rectangular area. The rectangular area is considered to intersect the
Shape if any point is contained in both the interior of the
Shape and the specified rectangular area.
The Shape.intersects() method allows a Shape implementation to conservatively return true when:
Shape intersect, but Shapes this method might return
true even though the rectangular area does not intersect the
Shape. The
Area class performs more accurate computations of geometric intersection than most
Shape objects and therefore can be used if a more precise answer is required.
intersects in interface
Shape
x - the X coordinate of the upper-left corner of the specified rectangular area
y - the Y coordinate of the upper-left corner of the specified rectangular area
w - the width of the specified rectangular area
h - the height of the specified rectangular area
true if the interior of the
Shape and the interior of the rectangular area intersect, or are both highly likely to intersect and intersection calculations would be too expensive to perform;
false otherwise.
Area
public boolean intersects(Rectangle2Dr)
Shape intersects the interior of a specified
Rectangle2D. The
Shape.intersects() method allows a
Shape implementation to conservatively return
true when:
Rectangle2D and the Shape intersect, but Shapes this method might return
true even though the
Rectangle2D does not intersect the
Shape. The
Area class performs more accurate computations of geometric intersection than most
Shape objects and therefore can be used if a more precise answer is required.
intersects in interface
Shape
r - the specified
Rectangle2D
true if the interior of the
Shape and the interior of the specified
Rectangle2D intersect, or are both highly likely to intersect and intersection calculations would be too expensive to perform;
false otherwise.
Shape.intersects(double, double, double, double)
public boolean contains(double x,
double y,
double w,
double h)
Line2D entirely contains the specified set of rectangular coordinates. This method is required to implement the
Shape interface, but in the case of
Line2D objects it always returns false since a line contains no area.
contains in interface
Shape
x - the X coordinate of the upper-left corner of the specified rectangular area
y - the Y coordinate of the upper-left corner of the specified rectangular area
w - the width of the specified rectangular area
h - the height of the specified rectangular area
false because a
Line2D contains no area.
Area,
Shape.intersects(double, double, double, double)
public boolean contains(Rectangle2Dr)
Line2D entirely contains the specified
Rectangle2D. This method is required to implement the
Shape interface, but in the case of
Line2D objects it always returns
false since a line contains no area.
contains in interface
Shape
r - the specified
Rectangle2D to be tested
false because a
Line2D contains no area.
Shape.contains(double, double, double, double)
public RectanglegetBounds()
Rectangle that completely encloses the
Shape. Note that there is no guarantee that the returned
Rectangle is the smallest bounding box that encloses the
Shape, only that the
Shape lies entirely within the indicated
Rectangle. The returned
Rectangle might also fail to completely enclose the
Shape if the
Shape overflows the limited range of the integer data type. The
getBounds2D method generally returns a tighter bounding box due to its greater flexibility in representation.
Note that the definition of insideness can lead to situations where points on the defining outline of the shape may not be considered contained in the returned bounds object, but only in cases where those points are also not considered contained in the original shape.
If a point is inside the shape according to the contains(point) method, then it must be inside the returned Rectangle bounds object according to the contains(point) method of the bounds. Specifically:
shape.contains(x,y) requires bounds.contains(x,y)
If a point is not inside the shape, then it might still be contained in the bounds object:
bounds.contains(x,y) does not imply shape.contains(x,y)
getBounds in interface
Shape
Rectangle that completely encloses the
Shape.
Shape.getBounds2D()
public PathIteratorgetPathIterator(AffineTransform at)
Line2D. The iterator for this class is not multi-threaded safe, which means that this
Line2D class does not guarantee that modifications to the geometry of this
Line2D object do not affect any iterations of that geometry that are already in process.
getPathIterator in interface
Shape
at - the specified
AffineTransform
PathIterator that defines the boundary of this
Line2D.
public PathIteratorgetPathIterator(AffineTransform at, double flatness)
Line2D. The iterator for this class is not multi-threaded safe, which means that this
Line2D class does not guarantee that modifications to the geometry of this
Line2D object do not affect any iterations of that geometry that are already in process.
getPathIterator in interface
Shape
at - the specified
AffineTransform
flatness - the maximum amount that the control points for a given curve can vary from colinear before a subdivided curve is replaced by a straight line connecting the end points. Since a
Line2D object is always flat, this parameter is ignored.
PathIterator that defines the boundary of the flattened
Line2D
public Objectclone()
clone in class
Object
OutOfMemoryError - if there is not enough memory.
Cloneable