Java java.awt.geom Class Ellipse2D（JDK8）

Constructor Detail

• Ellipse2D

  protected Ellipse2D()

  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.

  Since:

  1.2

  See Also:

  Ellipse2D.Float, Ellipse2D.Double

Method Detail

• contains

  public boolean contains(double x,
                          double y)

  Tests if the specified coordinates are inside the boundary of the Shape, as described by the definition of insideness.

  Parameters:

  x - the specified X coordinate to be tested

  y - the specified Y coordinate to be tested

  Returns:

  true if the specified coordinates are inside the Shape boundary; false otherwise.

  Since:

  1.2

• intersects

  public 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. 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:

  • there is a high probability that the rectangular area and the Shape intersect, but
  • the calculations to accurately determine this intersection are prohibitively expensive.

  This means that for some 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.

  Parameters:

  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

  Returns:

  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.

  Since:

  1.2

  See Also:

  Area

• contains

  public boolean contains(double x,
                          double y,
                          double w,
                          double h)

  Tests if the interior of the Shape entirely contains the specified rectangular area. All coordinates that lie inside the rectangular area must lie within the Shape for the entire rectangular area to be considered contained within the Shape.

  The Shape.contains() method allows a Shape implementation to conservatively return false when:

  • the intersect method returns true and
  • the calculations to determine whether or not the Shape entirely contains the rectangular area are prohibitively expensive.

  This means that for some Shapes this method might return false even though the Shape contains the rectangular area. The Area class performs more accurate geometric computations than most Shape objects and therefore can be used if a more precise answer is required.

  Parameters:

  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

  Returns:

  true if the interior of the Shape entirely contains the specified rectangular area; false otherwise or, if the Shape contains the rectangular area and the intersects method returns true and the containment calculations would be too expensive to perform.

  Since:

  1.2

  See Also:

  Area, Shape.intersects(double, double, double, double)

• getPathIterator

  public PathIterator getPathIterator(AffineTransform at)

  Returns an iteration object that defines the boundary of this Ellipse2D. The iterator for this class is multi-threaded safe, which means that this Ellipse2D class guarantees that modifications to the geometry of this Ellipse2D object 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 untransformed coordinates are desired

  Returns:

  the PathIterator object that returns the geometry of the outline of this Ellipse2D, one segment at a time.

  Since:

  1.2

• hashCode

  public int hashCode()

  Returns the hashcode for this Ellipse2D.

  Overrides:

  hashCode in class Object

  Returns:

  the hashcode for this Ellipse2D.

  Since:

  1.6

  See Also:

  Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)

• equals

  public boolean equals(Object obj)

  Determines whether or not the specified Object is equal to this Ellipse2D. The specified Object is equal to this Ellipse2D if it is an instance of Ellipse2D and if its location and size are the same as this Ellipse2D.

  Overrides:

  equals in class Object

  Parameters:

  obj - an Object to be compared with this Ellipse2D.

  Returns:

  true if obj is an instance of Ellipse2D and has the same values; false otherwise.

  Since:

  1.6

  See Also:

  Object.hashCode(), HashMap