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

Fields

Modifier and Type Field and Description
static ECPoint POINT_INFINITY

This defines the point at infinity.

Constructors

Constructor and Description
ECPoint(BigInteger x, BigInteger y)

Creates an ECPoint from the specified affine x-coordinate x and affine y-coordinate y.

Methods

Modifier and Type Method and Description
boolean equals(Object obj)

Compares this elliptic curve point for equality with the specified object.
BigInteger getAffineX()

Returns the affine x-coordinate x.
BigInteger getAffineY()

Returns the affine y-coordinate y.
int hashCode()

Returns a hash code value for this elliptic curve point.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Fields

POINT_INFINITY

public static final ECPoint POINT_INFINITY

This defines the point at infinity.

Constructors

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.

Methods

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

hashCode

public int hashCode()

Returns a hash code value for this elliptic curve point.

Overrides:
hashCode in class Object
Returns:
a hash code value.
See Also:
Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)

© 1993, 2020, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.
https://docs.oracle.com/javase/8/docs/api/java/security/spec/ECPoint.html