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 | |
|---|---|
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 | |
|---|---|
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:
|