Class ECPoint

java.lang.Object

java.security.spec.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	Description
static final ECPoint	POINT_INFINITY	This defines the point at infinity.

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method	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 the hash code value for this elliptic curve point.

Methods declared in class Object

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

Modifier and Type	Method	Description
protected Object	clone()	Answers a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
protected void	finalize()	Deprecated, for removal: This API element is subject to removal in a future version. May cause performance issues, deadlocks and hangs.
final Class<? extends Object>	getClass()	Answers the unique instance of java.lang.Class which represents the class of the receiver.
final void	notify()	Causes one thread which is waiting on the receiver to be made ready to run.
final void	notifyAll()	Causes all threads which are waiting on the receiver to be made ready to run.
String	toString()	Answers a string containing a concise, human-readable description of the receiver.
final void	wait()	Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by notify or notifyAll).
final void	wait(long time)	Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.
final void	wait(long time, int frac)	Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.

Field Details

POINT_INFINITY

public static final ECPoint POINT_INFINITY

This defines the point at infinity.

Constructor Details

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 Details

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()

hashCode

public int hashCode()

Returns the hash code value for this elliptic curve point.

Overrides:

hashCode in class Object

Returns:

the hash code value for this elliptic curve point

See Also:

• Object.equals(Object)