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package java.security.spec;

import java.math.BigInteger;
import java.util.Objects;

A class representing elliptic curve public keys as defined in RFC 7748, including the curve and other algorithm parameters. The public key is a particular point on the curve, which is represented using only its u-coordinate. A u-coordinate is an element of the field of integers modulo some value that is determined by the algorithm parameters. This field element is represented by a BigInteger which may hold any value. That is, the BigInteger is not restricted to the range of canonical field elements.
Since:11
/** * A class representing elliptic curve public keys as defined in RFC 7748, * including the curve and other algorithm parameters. The public key is a * particular point on the curve, which is represented using only its * u-coordinate. A u-coordinate is an element of the field of integers modulo * some value that is determined by the algorithm parameters. This field * element is represented by a BigInteger which may hold any value. That is, * the BigInteger is not restricted to the range of canonical field elements. * * @since 11 */
public class XECPublicKeySpec implements KeySpec { private final AlgorithmParameterSpec params; private final BigInteger u;
Construct a public key spec using the supplied parameters and u coordinate.
Params:
  • params – the algorithm parameters
  • u – the u-coordinate of the point, represented using a BigInteger which may hold any value
Throws:
/** * Construct a public key spec using the supplied parameters and * u coordinate. * * @param params the algorithm parameters * @param u the u-coordinate of the point, represented using a BigInteger * which may hold any value * * @throws NullPointerException if {@code params} or {@code u} * is null. */
public XECPublicKeySpec(AlgorithmParameterSpec params, BigInteger u) { Objects.requireNonNull(params, "params must not be null"); Objects.requireNonNull(u, "u must not be null"); this.params = params; this.u = u; }
Get the algorithm parameters that define the curve and other settings.
Returns:the parameters
/** * Get the algorithm parameters that define the curve and other settings. * * @return the parameters */
public AlgorithmParameterSpec getParams() { return params; }
Get the u coordinate of the point.
Returns:the u-coordinate, represented using a BigInteger which may hold any value
/** * Get the u coordinate of the point. * * @return the u-coordinate, represented using a BigInteger which may hold * any value */
public BigInteger getU() { return u; } }