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 | |
---|---|
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 | |
---|---|
obj |
Object : the object to be compared. |
Returns | |
---|---|
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:
|