- java.lang.Object
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- java.security.spec.EllipticCurve
 
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 public class EllipticCurve extends Object This immutable class holds the necessary values needed to represent an elliptic curve.- Since:
- 1.5
- See Also:
- ECField,- ECFieldFp,- ECFieldF2m
 
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Constructor SummaryConstructors Constructor Description EllipticCurve(ECField field, BigInteger a, BigInteger b)Creates an elliptic curve with the specified elliptic fieldfieldand the coefficientsaandb.EllipticCurve(ECField field, BigInteger a, BigInteger b, byte[] seed)Creates an elliptic curve with the specified elliptic fieldfield, the coefficientsaandb, and theseedused for curve generation.
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Method SummaryAll Methods Instance Methods Concrete Methods Modifier and Type Method Description booleanequals(Object obj)Compares this elliptic curve for equality with the specified object.BigIntegergetA()Returns the first coefficientaof the elliptic curve.BigIntegergetB()Returns the second coefficientbof the elliptic curve.ECFieldgetField()Returns the finite fieldfieldthat this elliptic curve is over.byte[]getSeed()Returns the seeding bytesseedused during curve generation.inthashCode()Returns a hash code value for this elliptic curve.
 
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Constructor Detail- 
EllipticCurvepublic EllipticCurve(ECField field, BigInteger a, BigInteger b) Creates an elliptic curve with the specified elliptic fieldfieldand the coefficientsaandb.- Parameters:
- field- the finite field that this elliptic curve is over.
- a- the first coefficient of this elliptic curve.
- b- the second coefficient of this elliptic curve.
- Throws:
- NullPointerException- if- field,- a, or- bis null.
- IllegalArgumentException- if- aor- bis not null and not in- field.
 
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EllipticCurvepublic EllipticCurve(ECField field, BigInteger a, BigInteger b, byte[] seed) Creates an elliptic curve with the specified elliptic fieldfield, the coefficientsaandb, and theseedused for curve generation.- Parameters:
- field- the finite field that this elliptic curve is over.
- a- the first coefficient of this elliptic curve.
- b- the second coefficient of this elliptic curve.
- seed- 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- bis null.
- IllegalArgumentException- if- aor- bis not null and not in- field.
 
 
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Method Detail- 
getFieldpublic ECField getField() Returns the finite fieldfieldthat this elliptic curve is over.- Returns:
- the field fieldthat this curve is over.
 
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getApublic BigInteger getA() Returns the first coefficientaof the elliptic curve.- Returns:
- the first coefficient a.
 
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getBpublic BigInteger getB() Returns the second coefficientbof the elliptic curve.- Returns:
- the second coefficient b.
 
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getSeedpublic byte[] getSeed() Returns the seeding bytesseedused during curve generation. May be null if not specified.- Returns:
- the seeding bytes seed. A new array is returned each time this method is called.
 
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equalspublic boolean equals(Object obj) Compares this elliptic curve for equality with the specified object.- Overrides:
- equalsin class- Object
- Parameters:
- obj- the object to be compared.
- Returns:
- true if objis an instance of EllipticCurve and the field, A, and B match, false otherwise.
- See Also:
- Object.hashCode(),- HashMap
 
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hashCodepublic int hashCode() Returns a hash code value for this elliptic curve.- Overrides:
- hashCodein class- Object
- Returns:
- a hash code value computed from the hash codes of the field, A,
 and B, as follows:
 (field.hashCode() << 6) + (a.hashCode() << 4) + (b.hashCode() << 2)
- See Also:
- Object.equals(java.lang.Object),- System.identityHashCode(java.lang.Object)
 
 
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