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java.awt.geom
abstract public class: Path2D [javadoc | source]
java.lang.Object
   java.awt.geom.Path2D

All Implemented Interfaces:
    Shape, Cloneable

Direct Known Subclasses:
    GeneralPath, Float, Double

The {@code Path2D} class provides a simple, yet flexible shape which represents an arbitrary geometric path. It can fully represent any path which can be iterated by the PathIterator interface including all of its segment types and winding rules and it implements all of the basic hit testing methods of the Shape interface.

Use Path2D.Float when dealing with data that can be represented and used with floating point precision. Use Path2D.Double for data that requires the accuracy or range of double precision.

{@code Path2D} provides exactly those facilities required for basic construction and management of a geometric path and implementation of the above interfaces with little added interpretation. If it is useful to manipulate the interiors of closed geometric shapes beyond simple hit testing then the Area class provides additional capabilities specifically targeted at closed figures. While both classes nominally implement the {@code Shape} interface, they differ in purpose and together they provide two useful views of a geometric shape where {@code Path2D} deals primarily with a trajectory formed by path segments and {@code Area} deals more with interpretation and manipulation of enclosed regions of 2D geometric space.

The PathIterator interface has more detailed descriptions of the types of segments that make up a path and the winding rules that control how to determine which regions are inside or outside the path.

Nested Class Summary:
public static class  Path2D.Float  The {@code Float} class defines a geometric path with coordinates stored in single precision floating point. 
public static class  Path2D.Double  The {@code Double} class defines a geometric path with coordinates stored in double precision floating point. 
abstract static class  Path2D.Iterator   
Field Summary
public static final  int WIND_EVEN_ODD    An even-odd winding rule for determining the interior of a path.
    Also see:
    PathIterator#WIND_EVEN_ODD
    since: 1.6 -
 
public static final  int WIND_NON_ZERO    A non-zero winding rule for determining the interior of a path.
    Also see:
    PathIterator#WIND_NON_ZERO
    since: 1.6 -
 
transient  byte[] pointTypes     
transient  int numTypes     
transient  int numCoords     
transient  int windingRule     
static final  int INIT_SIZE     
static final  int EXPAND_MAX     
Constructor:
 Path2D() 
 Path2D(int rule,
    int initialTypes) 
Method from java.awt.geom.Path2D Summary:
append,   append,   append,   append,   clone,   cloneCoordsDouble,   cloneCoordsFloat,   closePath,   contains,   contains,   contains,   contains,   contains,   contains,   contains,   contains,   createTransformedShape,   curveTo,   getBounds,   getCurrentPoint,   getPathIterator,   getPoint,   getWindingRule,   intersects,   intersects,   intersects,   intersects,   lineTo,   moveTo,   needRoom,   pointCrossings,   quadTo,   readObject,   rectCrossings,   reset,   setWindingRule,   transform,   writeObject
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from java.awt.geom.Path2D Detail:
 abstract  void append(float x,
    float y)
 abstract  void append(double x,
    double y)
 public final  void append(Shape s,
    boolean connect) 
    Appends the geometry of the specified {@code Shape} object to the path, possibly connecting the new geometry to the existing path segments with a line segment. If the {@code connect} parameter is {@code true} and the path is not empty then any initial {@code moveTo} in the geometry of the appended {@code Shape} is turned into a {@code lineTo} segment. If the destination coordinates of such a connecting {@code lineTo} segment match the ending coordinates of a currently open subpath then the segment is omitted as superfluous. The winding rule of the specified {@code Shape} is ignored and the appended geometry is governed by the winding rule specified for this path.
 abstract public  void append(PathIterator pi,
    boolean connect)
    Appends the geometry of the specified PathIterator object to the path, possibly connecting the new geometry to the existing path segments with a line segment. If the {@code connect} parameter is {@code true} and the path is not empty then any initial {@code moveTo} in the geometry of the appended {@code Shape} is turned into a {@code lineTo} segment. If the destination coordinates of such a connecting {@code lineTo} segment match the ending coordinates of a currently open subpath then the segment is omitted as superfluous. The winding rule of the specified {@code Shape} is ignored and the appended geometry is governed by the winding rule specified for this path.
 abstract public Object clone()
    Creates a new object of the same class as this object.
 abstract double[] cloneCoordsDouble(AffineTransform at)
 abstract float[] cloneCoordsFloat(AffineTransform at)
 public final synchronized  void closePath() 
    Closes the current subpath by drawing a straight line back to the coordinates of the last {@code moveTo}. If the path is already closed then this method has no effect.
 public final boolean contains(Point2D p) 
    {@inheritDoc}
 public final boolean contains(Rectangle2D r) 
    {@inheritDoc}

    This method object may conservatively return false in cases where the specified rectangular area intersects a segment of the path, but that segment does not represent a boundary between the interior and exterior of the path. Such segments could lie entirely within the interior of the path if they are part of a path with a #WIND_NON_ZERO winding rule or if the segments are retraced in the reverse direction such that the two sets of segments cancel each other out without any exterior area falling between them. To determine whether segments represent true boundaries of the interior of the path would require extensive calculations involving all of the segments of the path and the winding rule and are thus beyond the scope of this implementation.

 public static boolean contains(PathIterator pi,
    Point2D p) 
 public final boolean contains(double x,
    double y) 
    {@inheritDoc}
 public static boolean contains(PathIterator pi,
    Rectangle2D r) 
    Tests if the specified Rectangle2D is entirely inside the closed boundary of the specified PathIterator .

    This method provides a basic facility for implementors of the Shape interface to implement support for the Shape#contains(Rectangle2D) method.

    This method object may conservatively return false in cases where the specified rectangular area intersects a segment of the path, but that segment does not represent a boundary between the interior and exterior of the path. Such segments could lie entirely within the interior of the path if they are part of a path with a #WIND_NON_ZERO winding rule or if the segments are retraced in the reverse direction such that the two sets of segments cancel each other out without any exterior area falling between them. To determine whether segments represent true boundaries of the interior of the path would require extensive calculations involving all of the segments of the path and the winding rule and are thus beyond the scope of this implementation.

 public static boolean contains(PathIterator pi,
    double x,
    double y) 
    Tests if the specified coordinates are inside the closed boundary of the specified PathIterator .

    This method provides a basic facility for implementors of the Shape interface to implement support for the Shape#contains(double, double) method.

 public final boolean contains(double x,
    double y,
    double w,
    double h) 
    {@inheritDoc}

    This method object may conservatively return false in cases where the specified rectangular area intersects a segment of the path, but that segment does not represent a boundary between the interior and exterior of the path. Such segments could lie entirely within the interior of the path if they are part of a path with a #WIND_NON_ZERO winding rule or if the segments are retraced in the reverse direction such that the two sets of segments cancel each other out without any exterior area falling between them. To determine whether segments represent true boundaries of the interior of the path would require extensive calculations involving all of the segments of the path and the winding rule and are thus beyond the scope of this implementation.

 public static boolean contains(PathIterator pi,
    double x,
    double y,
    double w,
    double h) 
    Tests if the specified rectangular area is entirely inside the closed boundary of the specified PathIterator .

    This method provides a basic facility for implementors of the Shape interface to implement support for the Shape#contains(double, double, double, double) method.

    This method object may conservatively return false in cases where the specified rectangular area intersects a segment of the path, but that segment does not represent a boundary between the interior and exterior of the path. Such segments could lie entirely within the interior of the path if they are part of a path with a #WIND_NON_ZERO winding rule or if the segments are retraced in the reverse direction such that the two sets of segments cancel each other out without any exterior area falling between them. To determine whether segments represent true boundaries of the interior of the path would require extensive calculations involving all of the segments of the path and the winding rule and are thus beyond the scope of this implementation.

 public final synchronized Shape createTransformedShape(AffineTransform at) 
    Returns a new {@code Shape} representing a transformed version of this {@code Path2D}. Note that the exact type and coordinate precision of the return value is not specified for this method. The method will return a Shape that contains no less precision for the transformed geometry than this {@code Path2D} currently maintains, but it may contain no more precision either. If the tradeoff of precision vs. storage size in the result is important then the convenience constructors in the Path2D.Float and Path2D.Double subclasses should be used to make the choice explicit.
 abstract public  void curveTo(double x1,
    double y1,
    double x2,
    double y2,
    double x3,
    double y3)
    Adds a curved segment, defined by three new points, to the path by drawing a Bézier curve that intersects both the current coordinates and the specified coordinates {@code (x3,y3)}, using the specified points {@code (x1,y1)} and {@code (x2,y2)} as Bézier control points. All coordinates are specified in double precision.
 public final Rectangle getBounds() 
    {@inheritDoc}
 public final synchronized Point2D getCurrentPoint() 
    Returns the coordinates most recently added to the end of the path as a Point2D object.
 public final PathIterator getPathIterator(AffineTransform at,
    double flatness) 
    {@inheritDoc}

    The iterator for this class is not multi-threaded safe, which means that this {@code Path2D} class does not guarantee that modifications to the geometry of this {@code Path2D} object do not affect any iterations of that geometry that are already in process.

 abstract Point2D getPoint(int coordindex)
 public final synchronized int getWindingRule() 
    Returns the fill style winding rule.
 public final boolean intersects(Rectangle2D r) 
    {@inheritDoc}

    This method object may conservatively return true in cases where the specified rectangular area intersects a segment of the path, but that segment does not represent a boundary between the interior and exterior of the path. Such a case may occur if some set of segments of the path are retraced in the reverse direction such that the two sets of segments cancel each other out without any interior area between them. To determine whether segments represent true boundaries of the interior of the path would require extensive calculations involving all of the segments of the path and the winding rule and are thus beyond the scope of this implementation.

 public static boolean intersects(PathIterator pi,
    Rectangle2D r) 
    Tests if the interior of the specified PathIterator intersects the interior of a specified Rectangle2D .

    This method provides a basic facility for implementors of the Shape interface to implement support for the Shape#intersects(Rectangle2D) method.

    This method object may conservatively return true in cases where the specified rectangular area intersects a segment of the path, but that segment does not represent a boundary between the interior and exterior of the path. Such a case may occur if some set of segments of the path are retraced in the reverse direction such that the two sets of segments cancel each other out without any interior area between them. To determine whether segments represent true boundaries of the interior of the path would require extensive calculations involving all of the segments of the path and the winding rule and are thus beyond the scope of this implementation.

 public final boolean intersects(double x,
    double y,
    double w,
    double h) 
    {@inheritDoc}

    This method object may conservatively return true in cases where the specified rectangular area intersects a segment of the path, but that segment does not represent a boundary between the interior and exterior of the path. Such a case may occur if some set of segments of the path are retraced in the reverse direction such that the two sets of segments cancel each other out without any interior area between them. To determine whether segments represent true boundaries of the interior of the path would require extensive calculations involving all of the segments of the path and the winding rule and are thus beyond the scope of this implementation.

 public static boolean intersects(PathIterator pi,
    double x,
    double y,
    double w,
    double h) 
    Tests if the interior of the specified PathIterator intersects the interior of a specified set of rectangular coordinates.

    This method provides a basic facility for implementors of the Shape interface to implement support for the Shape#intersects(double, double, double, double) method.

    This method object may conservatively return true in cases where the specified rectangular area intersects a segment of the path, but that segment does not represent a boundary between the interior and exterior of the path. Such a case may occur if some set of segments of the path are retraced in the reverse direction such that the two sets of segments cancel each other out without any interior area between them. To determine whether segments represent true boundaries of the interior of the path would require extensive calculations involving all of the segments of the path and the winding rule and are thus beyond the scope of this implementation.

 abstract public  void lineTo(double x,
    double y)
    Adds a point to the path by drawing a straight line from the current coordinates to the new specified coordinates specified in double precision.
 abstract public  void moveTo(double x,
    double y)
    Adds a point to the path by moving to the specified coordinates specified in double precision.
 abstract  void needRoom(boolean needMove,
    int newCoords)
 abstract int pointCrossings(double px,
    double py)
 abstract public  void quadTo(double x1,
    double y1,
    double x2,
    double y2)
    Adds a curved segment, defined by two new points, to the path by drawing a Quadratic curve that intersects both the current coordinates and the specified coordinates {@code (x2,y2)}, using the specified point {@code (x1,y1)} as a quadratic parametric control point. All coordinates are specified in double precision.
 final  void readObject(ObjectInputStream s,
    boolean storedbl) throws ClassNotFoundException, IOException 
 abstract int rectCrossings(double rxmin,
    double rymin,
    double rxmax,
    double rymax)
 public final synchronized  void reset() 
    Resets the path to empty. The append position is set back to the beginning of the path and all coordinates and point types are forgotten.
 public final  void setWindingRule(int rule) 
    Sets the winding rule for this path to the specified value.
 abstract public  void transform(AffineTransform at)
    Transforms the geometry of this path using the specified AffineTransform . The geometry is transformed in place, which permanently changes the boundary defined by this object.
 final  void writeObject(ObjectOutputStream s,
    boolean isdbl) throws IOException