# Class Arc2D

java.lang.Object
java.awt.geom.RectangularShape
java.awt.geom.Arc2D

All Implemented Interfaces:
  `Shape, Cloneable`

Direct Known Subclasses:
  `Arc2D.Double, Arc2D.Float`

public abstract class Arc2D extends RectangularShape
`Arc2D` is the abstract superclass for all objects that store a 2D arc defined by a framing rectangle, start angle, angular extent (length of the arc), and a closure type (`OPEN`, `CHORD`, or `PIE`).

The arc is a partial section of a full ellipse which inscribes the framing rectangle of its parent `RectangularShape`. The angles are specified relative to the non-square framing rectangle such that 45 degrees always falls on the line from the center of the ellipse to the upper right corner of the framing rectangle. As a result, if the framing rectangle is noticeably longer along one axis than the other, the angles to the start and end of the arc segment will be skewed farther along the longer axis of the frame.

The actual storage representation of the coordinates is left to the subclass.

Since:
  1.2

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `static class`
  `Arc2D.Double`
  This class defines an arc specified in `double` precision.
  `static class`
  `Arc2D.Float`
  This class defines an arc specified in `float` precision.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final int`
  `CHORD`
  The closure type for an arc closed by drawing a straight line segment from the start of the arc segment to the end of the arc segment.
  `static final int`
  `OPEN`
  The closure type for an open arc with no path segments connecting the two ends of the arc segment.
  `static final int`
  `PIE`
  The closure type for an arc closed by drawing straight line segments from the start of the arc segment to the center of the full ellipse and from that point to the end of the arc segment.

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `Arc2D()`
  This is an abstract class that cannot be instantiated directly.
  `protected`
  `Arc2D(int type)`
  This is an abstract class that cannot be instantiated directly.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `boolean`
  `contains(double x, double y)`
  Determines whether or not the specified point is inside the boundary of the arc.
  `boolean`
  `contains(double x, double y, double w, double h)`
  Determines whether or not the interior of the arc entirely contains the specified rectangle.
  `boolean`
  `contains(Rectangle2D r)`
  Determines whether or not the interior of the arc entirely contains the specified rectangle.
  `boolean`
  `containsAngle(double angle)`
  Determines whether or not the specified angle is within the angular extents of the arc.
  `boolean`
  `equals(Object obj)`
  Determines whether or not the specified `Object` is equal to this `Arc2D`.
  `abstract double`
  `getAngleExtent()`
  Returns the angular extent of the arc.
  `abstract double`
  `getAngleStart()`
  Returns the starting angle of the arc.
  `int`
  `getArcType()`
  Returns the arc closure type of the arc: `OPEN`, `CHORD`, or `PIE`.
  `Rectangle2D`
  `getBounds2D()`
  Returns the high-precision framing rectangle of the arc.
  `Point2D`
  `getEndPoint()`
  Returns the ending point of the arc.
  `PathIterator`
  `getPathIterator(AffineTransform at)`
  Returns an iteration object that defines the boundary of the arc.
  `Point2D`
  `getStartPoint()`
  Returns the starting point of the arc.
  `int`
  `hashCode()`
  Returns the hashcode for this `Arc2D`.
  `boolean`
  `intersects(double x, double y, double w, double h)`
  Determines whether or not the interior of the arc intersects the interior of the specified rectangle.
  `protected abstract Rectangle2D`
  `makeBounds(double x, double y, double w, double h)`
  Constructs a `Rectangle2D` of the appropriate precision to hold the parameters calculated to be the framing rectangle of this arc.
  `abstract void`
  `setAngleExtent(double angExt)`
  Sets the angular extent of this arc to the specified double value.
  `void`
  `setAngles(double x1, double y1, double x2, double y2)`
  Sets the starting angle and angular extent of this arc using two sets of coordinates.
  `void`
  `setAngles(Point2D p1, Point2D p2)`
  Sets the starting angle and angular extent of this arc using two points.
  `abstract void`
  `setAngleStart(double angSt)`
  Sets the starting angle of this arc to the specified double value.
  `void`
  `setAngleStart(Point2D p)`
  Sets the starting angle of this arc to the angle that the specified point defines relative to the center of this arc.
  `abstract void`
  `setArc(double x, double y, double w, double h, double angSt, double angExt, int closure)`
  Sets the location, size, angular extents, and closure type of this arc to the specified double values.
  `void`
  `setArc(Arc2D a)`
  Sets this arc to be the same as the specified arc.
  `void`
  `setArc(Point2D loc, Dimension2D size, double angSt, double angExt, int closure)`
  Sets the location, size, angular extents, and closure type of this arc to the specified values.
  `void`
  `setArc(Rectangle2D rect, double angSt, double angExt, int closure)`
  Sets the location, size, angular extents, and closure type of this arc to the specified values.
  `void`
  `setArcByCenter(double x, double y, double radius, double angSt, double angExt, int closure)`
  Sets the position, bounds, angular extents, and closure type of this arc to the specified values.
  `void`
  `setArcByTangent(Point2D p1, Point2D p2, Point2D p3, double radius)`
  Sets the position, bounds, and angular extents of this arc to the specified value.
  `void`
  `setArcType(int type)`
  Sets the closure type of this arc to the specified value: `OPEN`, `CHORD`, or `PIE`.
  `void`
  `setFrame(double x, double y, double w, double h)`
  Sets the location and size of the framing rectangle of this `Shape` to the specified rectangular values.

  ### Methods declared in class RectangularShape

  `clone, contains, getBounds, getCenterX, getCenterY, getFrame, getHeight, getMaxX, getMaxY, getMinX, getMinY, getPathIterator, getWidth, getX, getY, intersects, isEmpty, setFrame, setFrame, setFrameFromCenter, setFrameFromCenter, setFrameFromDiagonal, setFrameFromDiagonal`

  ### Methods declared in class Object

  `finalize, getClass, notify, notifyAll, toString, wait, wait, wait`

- ## Field Details

  - ### OPEN

    public static final int OPEN
    The closure type for an open arc with no path segments connecting the two ends of the arc segment.
    Since:
      1.2
    See Also:
      - Constant Field Values

  - ### CHORD

    public static final int CHORD
    The closure type for an arc closed by drawing a straight line segment from the start of the arc segment to the end of the arc segment.
    Since:
      1.2
    See Also:
      - Constant Field Values

  - ### PIE

    public static final int PIE
    The closure type for an arc closed by drawing straight line segments from the start of the arc segment to the center of the full ellipse and from that point to the end of the arc segment.
    Since:
      1.2
    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### Arc2D

    protected Arc2D()
    This is an abstract class that cannot be instantiated directly. Type-specific implementation subclasses are available for instantiation and provide a number of formats for storing the information necessary to satisfy the various accessor methods below.

    This constructor creates an object with a default closure type of `OPEN`. It is provided only to enable serialization of subclasses.

    See Also:
      - `Arc2D.Float`
      - `Arc2D.Double`

  - ### Arc2D

    protected Arc2D(int type)
    This is an abstract class that cannot be instantiated directly. Type-specific implementation subclasses are available for instantiation and provide a number of formats for storing the information necessary to satisfy the various accessor methods below.
    Parameters:
      `type` - The closure type of this arc: `OPEN`, `CHORD`, or `PIE`.
    Since:
      1.2
    See Also:
      - `Arc2D.Float`
      - `Arc2D.Double`

- ## Method Details

  - ### getAngleStart

    public abstract double getAngleStart()
    Returns the starting angle of the arc.
    Returns:
      A double value that represents the starting angle of the arc in degrees.
    Since:
      1.2
    See Also:
      - `setAngleStart(double)`

  - ### getAngleExtent

    public abstract double getAngleExtent()
    Returns the angular extent of the arc.
    Returns:
      A double value that represents the angular extent of the arc in degrees.
    Since:
      1.2
    See Also:
      - `setAngleExtent(double)`

  - ### getArcType

    public int getArcType()
    Returns the arc closure type of the arc: `OPEN`, `CHORD`, or `PIE`.
    Returns:
      One of the integer constant closure types defined in this class.
    Since:
      1.2
    See Also:
      - `setArcType(int)`

  - ### getStartPoint

    public Point2D getStartPoint()
    Returns the starting point of the arc. This point is the intersection of the ray from the center defined by the starting angle and the elliptical boundary of the arc.
    Returns:
      A `Point2D` object representing the x,y coordinates of the starting point of the arc.
    Since:
      1.2

  - ### getEndPoint

    public Point2D getEndPoint()
    Returns the ending point of the arc. This point is the intersection of the ray from the center defined by the starting angle plus the angular extent of the arc and the elliptical boundary of the arc.
    Returns:
      A `Point2D` object representing the x,y coordinates of the ending point of the arc.
    Since:
      1.2

  - ### setArc

    public abstract void setArc(double x, double y, double w, double h, double angSt, double angExt, int closure)
    Sets the location, size, angular extents, and closure type of this arc to the specified double values.
    Parameters:
      `x` - The X coordinate of the upper-left corner of the arc.
      `y` - The Y coordinate of the upper-left corner of the arc.
      `w` - The overall width of the full ellipse of which this arc is a partial section.
      `h` - The overall height of the full ellipse of which this arc is a partial section.
      `angSt` - The starting angle of the arc in degrees.
      `angExt` - The angular extent of the arc in degrees.
      `closure` - The closure type for the arc: `OPEN`, `CHORD`, or `PIE`.
    Since:
      1.2

  - ### setArc

    public void setArc(Point2D loc, Dimension2D size, double angSt, double angExt, int closure)
    Sets the location, size, angular extents, and closure type of this arc to the specified values.
    Parameters:
      `loc` - The `Point2D` representing the coordinates of the upper-left corner of the arc.
      `size` - The `Dimension2D` representing the width and height of the full ellipse of which this arc is a partial section.
      `angSt` - The starting angle of the arc in degrees.
      `angExt` - The angular extent of the arc in degrees.
      `closure` - The closure type for the arc: `OPEN`, `CHORD`, or `PIE`.
    Since:
      1.2

  - ### setArc

    public void setArc(Rectangle2D rect, double angSt, double angExt, int closure)
    Sets the location, size, angular extents, and closure type of this arc to the specified values.
    Parameters:
      `rect` - The framing rectangle that defines the outer boundary of the full ellipse of which this arc is a partial section.
      `angSt` - The starting angle of the arc in degrees.
      `angExt` - The angular extent of the arc in degrees.
      `closure` - The closure type for the arc: `OPEN`, `CHORD`, or `PIE`.
    Since:
      1.2

  - ### setArc

    public void setArc(Arc2D a)
    Sets this arc to be the same as the specified arc.
    Parameters:
      `a` - The `Arc2D` to use to set the arc's values.
    Since:
      1.2

  - ### setArcByCenter

    public void setArcByCenter(double x, double y, double radius, double angSt, double angExt, int closure)
    Sets the position, bounds, angular extents, and closure type of this arc to the specified values. The arc is defined by a center point and a radius rather than a framing rectangle for the full ellipse.
    Parameters:
      `x` - The X coordinate of the center of the arc.
      `y` - The Y coordinate of the center of the arc.
      `radius` - The radius of the arc.
      `angSt` - The starting angle of the arc in degrees.
      `angExt` - The angular extent of the arc in degrees.
      `closure` - The closure type for the arc: `OPEN`, `CHORD`, or `PIE`.
    Since:
      1.2

  - ### setArcByTangent

    public void setArcByTangent(Point2D p1, Point2D p2, Point2D p3, double radius)
    Sets the position, bounds, and angular extents of this arc to the specified value. The starting angle of the arc is tangent to the line specified by points (p1, p2), the ending angle is tangent to the line specified by points (p2, p3), and the arc has the specified radius.
    Parameters:
      `p1` - The first point that defines the arc. The starting angle of the arc is tangent to the line specified by points (p1, p2).
      `p2` - The second point that defines the arc. The starting angle of the arc is tangent to the line specified by points (p1, p2). The ending angle of the arc is tangent to the line specified by points (p2, p3).
      `p3` - The third point that defines the arc. The ending angle of the arc is tangent to the line specified by points (p2, p3).
      `radius` - The radius of the arc.
    Since:
      1.2

  - ### setAngleStart

    public abstract void setAngleStart(double angSt)
    Sets the starting angle of this arc to the specified double value.
    Parameters:
      `angSt` - The starting angle of the arc in degrees.
    Since:
      1.2
    See Also:
      - `getAngleStart()`

  - ### setAngleExtent

    public abstract void setAngleExtent(double angExt)
    Sets the angular extent of this arc to the specified double value.
    Parameters:
      `angExt` - The angular extent of the arc in degrees.
    Since:
      1.2
    See Also:
      - `getAngleExtent()`

  - ### setAngleStart

    public void setAngleStart(Point2D p)
    Sets the starting angle of this arc to the angle that the specified point defines relative to the center of this arc. The angular extent of the arc will remain the same.
    Parameters:
      `p` - The `Point2D` that defines the starting angle.
    Since:
      1.2
    See Also:
      - `getAngleStart()`

  - ### setAngles

    public void setAngles(double x1, double y1, double x2, double y2)
    Sets the starting angle and angular extent of this arc using two sets of coordinates. The first set of coordinates is used to determine the angle of the starting point relative to the arc's center. The second set of coordinates is used to determine the angle of the end point relative to the arc's center. The arc will always be non-empty and extend counterclockwise from the first point around to the second point.
    Parameters:
      `x1` - The X coordinate of the arc's starting point.
      `y1` - The Y coordinate of the arc's starting point.
      `x2` - The X coordinate of the arc's ending point.
      `y2` - The Y coordinate of the arc's ending point.
    Since:
      1.2

  - ### setAngles

    public void setAngles(Point2D p1, Point2D p2)
    Sets the starting angle and angular extent of this arc using two points. The first point is used to determine the angle of the starting point relative to the arc's center. The second point is used to determine the angle of the end point relative to the arc's center. The arc will always be non-empty and extend counterclockwise from the first point around to the second point.
    Parameters:
      `p1` - The `Point2D` that defines the arc's starting point.
      `p2` - The `Point2D` that defines the arc's ending point.
    Since:
      1.2

  - ### setArcType

    public void setArcType(int type)
    Sets the closure type of this arc to the specified value: `OPEN`, `CHORD`, or `PIE`.
    Parameters:
      `type` - The integer constant that represents the closure type of this arc: `OPEN`, `CHORD`, or `PIE`.
    Throws:
      `IllegalArgumentException` - if `type` is not 0, 1, or 2.+
    Since:
      1.2
    See Also:
      - `getArcType()`

  - ### setFrame

    public void setFrame(double x, double y, double w, double h)
    Sets the location and size of the framing rectangle of this `Shape` to the specified rectangular values. Note that the arc partially inscribes the framing rectangle of this `RectangularShape`.
    Specified by:
      `setFrame` in class `RectangularShape`
    Parameters:
      `x` - the X coordinate of the upper-left corner of the specified rectangular shape
      `y` - the Y coordinate of the upper-left corner of the specified rectangular shape
      `w` - the width of the specified rectangular shape
      `h` - the height of the specified rectangular shape
    Since:
      1.2
    See Also:
      - `RectangularShape.getFrame()`

  - ### getBounds2D

    public Rectangle2D getBounds2D()
    Returns the high-precision framing rectangle of the arc. The framing rectangle contains only the part of this `Arc2D` that is in between the starting and ending angles and contains the pie wedge, if this `Arc2D` has a `PIE` closure type.

    This method differs from the `getBounds` in that the `getBounds` method only returns the bounds of the enclosing ellipse of this `Arc2D` without considering the starting and ending angles of this `Arc2D`.

    Returns:
      the `Rectangle2D` that represents the arc's framing rectangle.
    Since:
      1.2
    See Also:
      - `Shape.getBounds()`

  - ### makeBounds

    protected abstract Rectangle2D makeBounds(double x, double y, double w, double h)
    Constructs a `Rectangle2D` of the appropriate precision to hold the parameters calculated to be the framing rectangle of this arc.
    Parameters:
      `x` - The X coordinate of the upper-left corner of the framing rectangle.
      `y` - The Y coordinate of the upper-left corner of the framing rectangle.
      `w` - The width of the framing rectangle.
      `h` - The height of the framing rectangle.
    Returns:
      a `Rectangle2D` that is the framing rectangle of this arc.
    Since:
      1.2

  - ### containsAngle

    public boolean containsAngle(double angle)
    Determines whether or not the specified angle is within the angular extents of the arc.
    Parameters:
      `angle` - The angle to test.
    Returns:
      `true` if the arc contains the angle, `false` if the arc doesn't contain the angle.
    Since:
      1.2

  - ### contains

    public boolean contains(double x, double y)
    Determines whether or not the specified point is inside the boundary of the arc.
    Parameters:
      `x` - The X coordinate of the point to test.
      `y` - The Y coordinate of the point to test.
    Returns:
      `true` if the point lies within the bound of the arc, `false` if the point lies outside of the arc's bounds.
    Since:
      1.2

  - ### intersects

    public boolean intersects(double x, double y, double w, double h)
    Determines whether or not the interior of the arc intersects the interior of the specified rectangle.
    Parameters:
      `x` - The X coordinate of the rectangle's upper-left corner.
      `y` - The Y coordinate of the rectangle's upper-left corner.
      `w` - The width of the rectangle.
      `h` - The height of the rectangle.
    Returns:
      `true` if the arc intersects the rectangle, `false` if the arc doesn't intersect the rectangle.
    Since:
      1.2
    See Also:
      - `Area`

  - ### contains

    public boolean contains(double x, double y, double w, double h)
    Determines whether or not the interior of the arc entirely contains the specified rectangle.
    Parameters:
      `x` - The X coordinate of the rectangle's upper-left corner.
      `y` - The Y coordinate of the rectangle's upper-left corner.
      `w` - The width of the rectangle.
      `h` - The height of the rectangle.
    Returns:
      `true` if the arc contains the rectangle, `false` if the arc doesn't contain the rectangle.
    Since:
      1.2
    See Also:
      - `Area`
      - `Shape.intersects(double, double, double, double)`

  - ### contains

    public boolean contains(Rectangle2D r)
    Determines whether or not the interior of the arc entirely contains the specified rectangle.
    Specified by:
      `contains` in interface `Shape`
    Overrides:
      `contains` in class `RectangularShape`
    Parameters:
      `r` - The `Rectangle2D` to test.
    Returns:
      `true` if the arc contains the rectangle, `false` if the arc doesn't contain the rectangle.
    Since:
      1.2
    See Also:
      - `Shape.contains(double, double, double, double)`

  - ### getPathIterator

    public PathIterator getPathIterator(AffineTransform at)
    Returns an iteration object that defines the boundary of the arc. This iterator is multithread safe. `Arc2D` guarantees that modifications to the geometry of the arc do not affect any iterations of that geometry that are already in process.
    Parameters:
      `at` - an optional `AffineTransform` to be applied to the coordinates as they are returned in the iteration, or null if the untransformed coordinates are desired.
    Returns:
      A `PathIterator` that defines the arc's boundary.
    Since:
      1.2

  - ### hashCode

    public int hashCode()
    Returns the hashcode for this `Arc2D`.
    Overrides:
      `hashCode` in class `Object`
    Returns:
      the hashcode for this `Arc2D`.
    Since:
      1.6
    See Also:
      - `Object.equals(java.lang.Object)`
      - `System.identityHashCode(Object)`

  - ### equals

    public boolean equals(Object obj)
    Determines whether or not the specified `Object` is equal to this `Arc2D`. The specified `Object` is equal to this `Arc2D` if it is an instance of `Arc2D` and if its location, size, arc extents and type are the same as this `Arc2D`.
    Overrides:
      `equals` in class `Object`
    Parameters:
      `obj` - an `Object` to be compared with this `Arc2D`.
    Returns:
      `true` if `obj` is an instance of `Arc2D` and has the same values; `false` otherwise.
    Since:
      1.6
    See Also:
      - `Object.hashCode()`
      - `HashMap`