Class ECPoint



  • public class ECPoint
    extends Object
    This immutable class represents a point on an elliptic curve (EC) in affine coordinates. Other coordinate systems can extend this class to represent this point in other coordinates.
    Since:
    1.5
    • Field Summary

      Fields

      Modifier and Type Field and Description
      static ECPoint POINT_INFINITY
      This defines the point at infinity.
    • Constructor Summary

      Constructors

      Constructor and Description
      ECPoint(BigInteger x, BigInteger y)
      Creates an ECPoint from the specified affine x-coordinate x and affine y-coordinate y.
    • Field Detail

      • POINT_INFINITY

        public static final ECPoint POINT_INFINITY
        This defines the point at infinity.
    • Constructor Detail

      • ECPoint

        public ECPoint(BigInteger x,
                       BigInteger y)
        Creates an ECPoint from the specified affine x-coordinate x and affine y-coordinate y.
        Parameters:
        x - the affine x-coordinate.
        y - the affine y-coordinate.
        Throws:
        NullPointerException - if x or y is null.
    • Method Detail

      • getAffineX

        public BigInteger getAffineX()
        Returns the affine x-coordinate x. Note: POINT_INFINITY has a null affine x-coordinate.
        Returns:
        the affine x-coordinate.
      • getAffineY

        public BigInteger getAffineY()
        Returns the affine y-coordinate y. Note: POINT_INFINITY has a null affine y-coordinate.
        Returns:
        the affine y-coordinate.
      • equals

        public boolean equals(Object obj)
        Compares this elliptic curve point for equality with the specified object.
        Overrides:
        equals in class  Object
        Parameters:
        obj - the object to be compared.
        Returns:
        true if obj is an instance of ECPoint and the affine coordinates match, false otherwise.
        See Also:
        Object.hashCode(), HashMap