IT. Expert System.

All Implemented Interfaces:

ECField

public class ECFieldF2m
extends Object
implements ECField

• Constructor Summary

  Constructors

  Constructor and Description
  ECFieldF2m(int m) Creates a new ECFieldF2m with 2^m elements with a normal basis.
  ECFieldF2m(int m, BigInteger rp) Creates a new ECFieldF2m with 2^m elements with a polynomial basis and the reduction polynomial based on rp.
  ECFieldF2m(int m, int[] ks) Creates a new ECFieldF2m with 2^m elements with a polynomial basis and the reduction polynomial based on ks.

• Method Summary

  Methods

  Modifier and Type	Method and Description
  boolean	equals(Object obj) Returns whether the specified object equals to this finite field.
  int	getFieldSize() Returns the size of this finite field (in bits).
  int	getM() Returns the exponent m for this finite field, with 2^m as the number of elements.
  int[]	getMidTermsOfReductionPolynomial() Returns a copy of the integer array containing the order of the middle term(s) of the reduction polynomial for a polynomial basis.
  BigInteger	getReductionPolynomial() Returns the base of the reduction polynomial with the n-th bit corresponding to the n-th coefficient of the reduction polynomial for a polynomial basis.
  int	hashCode() Returns the hashcode value for this finite field.

  • Methods inherited from class java.lang.Object

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

• Constructor Detail

  • ECFieldF2m

    public ECFieldF2m(int m)

    Creates a new ECFieldF2m with 2^m elements with a normal basis.

    Parameters:

    m - the exponent m for the number of elements.

    Throws:

    IllegalArgumentException - if m <= zero.

  • ECFieldF2m

    public ECFieldF2m(int m,
              BigInteger rp)

    Creates a new ECFieldF2m with 2^m elements with a polynomial basis and the reduction polynomial based on rp.

    The reduction polynomial must be either trinomial or pentanomial.

    Parameters:

    m - the exponent m for the number of elements.

    rp - the base of the reduction polynomial with the n-th bit corresponding to the n-th coefficient of the reduction polynomial.

    Throws:

    IllegalArgumentException - if m <= zero or the rp is invalid.

  • ECFieldF2m

    public ECFieldF2m(int m,
              int[] ks)

    Creates a new ECFieldF2m with 2^m elements with a polynomial basis and the reduction polynomial based on ks.

    The reduction polynomial must be either trinomial or pentanomial.

    Parameters:

    m - the exponent m for the number of elements.

    ks - the base of the reduction polynomial with coefficients given in descending order.

    Throws:

    IllegalArgumentException - if m <= zero or the reduction polynomial is not valid.

• Method Detail

  • equals

    public boolean equals(Object obj)

    Returns whether the specified object equals to this finite field.

    Overrides:

    equals in class Object

    Parameters:

    obj - the object to compare to this finite field.

    Returns:

    true if the specified object is equal to this finite field, otherwise false.

    See Also:

    Object.hashCode()

  • getFieldSize

    public int getFieldSize()

    Returns the size of this finite field (in bits).

    Specified by:

    getFieldSize in interface ECField

    Returns:

    the size of this finite field (in bits).

  • getM

    public int getM()

    Returns the exponent m for this finite field, with 2^m as the number of elements.

    Returns:

    the exponent m for this finite field

  • getMidTermsOfReductionPolynomial

    public int[] getMidTermsOfReductionPolynomial()

    Returns a copy of the integer array containing the order of the middle term(s) of the reduction polynomial for a polynomial basis.

    Returns:

    a copy of the integer array containing the order of the middle term(s) of the reduction polynomial for a polynomial basis or null for a normal basis.

  • getReductionPolynomial

    public BigInteger getReductionPolynomial()

    Returns the base of the reduction polynomial with the n-th bit corresponding to the n-th coefficient of the reduction polynomial for a polynomial basis.

    Returns:

    the base of the reduction polynomial with the n-th bit corresponding to the n-th coefficient of the reduction polynomial for a polynomial basis or null for a normal basis.

  • hashCode

    public int hashCode()

    Returns the hashcode value for this finite field.

    Overrides:

    hashCode in class Object

    Returns:

    the hashcode value for this finite field.

    See Also:

    Object.equals(java.lang.Object)