EllipticCurve
public class EllipticCurve
extends Object
java.lang.Object | |
↳ | java.security.spec.EllipticCurve |
This immutable class holds the necessary values needed to represent an elliptic curve.
See also:
Summary
Public constructors | |
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EllipticCurve(ECField field, BigInteger a, BigInteger b) Creates an elliptic curve with the specified elliptic field | |
EllipticCurve(ECField field, BigInteger a, BigInteger b, byte[] seed) Creates an elliptic curve with the specified elliptic field |
Public methods | |
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boolean | equals(Object obj) Compares this elliptic curve for equality with the specified object. |
BigInteger | getA() Returns the first coefficient |
BigInteger | getB() Returns the second coefficient |
ECField | getField() Returns the finite field |
byte[] | getSeed() Returns the seeding bytes |
int | hashCode() Returns a hash code value for this elliptic curve. |
Inherited methods | |
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Public constructors
EllipticCurve
public EllipticCurve (ECField field, BigInteger a, BigInteger b)
Creates an elliptic curve with the specified elliptic field field
and the coefficients a
and b
.
Parameters | |
---|---|
field | ECField : the finite field that this elliptic curve is over. |
a | BigInteger : the first coefficient of this elliptic curve. |
b | BigInteger : the second coefficient of this elliptic curve. |
Throws | |
---|---|
NullPointerException | if field , a , or b is null. |
IllegalArgumentException | if a or b is not null and not in field . |
EllipticCurve
public EllipticCurve (ECField field, BigInteger a, BigInteger b, byte[] seed)
Creates an elliptic curve with the specified elliptic field field
, the coefficients a
and b
, and the seed
used for curve generation.
Parameters | |
---|---|
field | ECField : the finite field that this elliptic curve is over. |
a | BigInteger : the first coefficient of this elliptic curve. |
b | BigInteger : the second coefficient of this elliptic curve. |
seed | byte : the bytes used during curve generation for later validation. Contents of this array are copied to protect against subsequent modification. |
Throws | |
---|---|
NullPointerException | if field , a , or b is null. |
IllegalArgumentException | if a or b is not null and not in field . |
Public methods
equals
public boolean equals (Object obj)
Compares this elliptic curve for equality with the specified object.
Parameters | |
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obj | Object : the object to be compared. |
Returns | |
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boolean | true if obj is an instance of EllipticCurve and the field, A, and B match, false otherwise. |
getA
public BigInteger getA ()
Returns the first coefficient a
of the elliptic curve.
Returns | |
---|---|
BigInteger | the first coefficient a . |
getB
public BigInteger getB ()
Returns the second coefficient b
of the elliptic curve.
Returns | |
---|---|
BigInteger | the second coefficient b . |
getField
public ECField getField ()
Returns the finite field field
that this elliptic curve is over.
Returns | |
---|---|
ECField | the field field that this curve is over. |
getSeed
public byte[] getSeed ()
Returns the seeding bytes seed
used during curve generation. May be null if not specified.
Returns | |
---|---|
byte[] | the seeding bytes seed . A new array is returned each time this method is called. |
hashCode
public int hashCode ()
Returns a hash code value for this elliptic curve.
Returns | |
---|---|
int | a hash code value computed from the hash codes of the field, A, and B, as follows:
|