下面列出了怎么用java.security.spec.EllipticCurve的API类实例代码及写法，或者点击链接到github查看源代码。
public static Optional<ECOperations> forParameters(ECParameterSpec params) {
EllipticCurve curve = params.getCurve();
if (!(curve.getField() instanceof ECFieldFp)) {
return Optional.empty();
}
ECFieldFp primeField = (ECFieldFp) curve.getField();
BigInteger three = BigInteger.valueOf(3);
if (!primeField.getP().subtract(curve.getA()).equals(three)) {
return Optional.empty();
}
IntegerFieldModuloP field = fields.get(primeField.getP());
if (field == null) {
return Optional.empty();
}
IntegerFieldModuloP orderField = orderFields.get(params.getOrder());
if (orderField == null) {
return Optional.empty();
}
ImmutableIntegerModuloP b = field.getElement(curve.getB());
ECOperations ecOps = new ECOperations(b, orderField);
return Optional.of(ecOps);
}
public static Optional<ECOperations> forParameters(ECParameterSpec params) {
EllipticCurve curve = params.getCurve();
if (!(curve.getField() instanceof ECFieldFp)) {
return Optional.empty();
}
ECFieldFp primeField = (ECFieldFp) curve.getField();
BigInteger three = BigInteger.valueOf(3);
if (!primeField.getP().subtract(curve.getA()).equals(three)) {
return Optional.empty();
}
IntegerFieldModuloP field = fields.get(primeField.getP());
if (field == null) {
return Optional.empty();
}
IntegerFieldModuloP orderField = orderFields.get(params.getOrder());
if (orderField == null) {
return Optional.empty();
}
ImmutableIntegerModuloP b = field.getElement(curve.getB());
ECOperations ecOps = new ECOperations(b, orderField);
return Optional.of(ecOps);
}
public BCDSTU4145PrivateKey(
org.ripple.bouncycastle.jce.spec.ECPrivateKeySpec spec)
{
this.d = spec.getD();
if (spec.getParams() != null) // can be null if implicitlyCA
{
ECCurve curve = spec.getParams().getCurve();
EllipticCurve ellipticCurve;
ellipticCurve = EC5Util.convertCurve(curve, spec.getParams().getSeed());
this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
}
else
{
this.ecSpec = null;
}
}
private TPMTPublic createTPMTPublic(PublicKey credentialPublicKey) {
TPMIAlgPublic type = null;
TPMIAlgHash nameAlg = TPMIAlgHash.TPM_ALG_SHA256;
TPMAObject objectAttributes = new TPMAObject(394354);
byte[] authPolicy = Base64UrlUtil.decode("nf_L82w4OuaZ-5ho3G3LidcVOIS-KAOSLBJBWL-tIq4");
TPMUPublicId unique = null;
TPMUPublicParms parameters = null;
if (credentialPublicKey instanceof ECPublicKey) {
ECPublicKey ecPublicKey = (ECPublicKey) credentialPublicKey;
EllipticCurve curve = ecPublicKey.getParams().getCurve();
parameters = new TPMSECCParms(
new byte[2],
new byte[2],
TPMEccCurve.create(curve),
new byte[2]
);
type = TPMIAlgPublic.TPM_ALG_ECDSA;
ECPoint ecPoint = ecPublicKey.getW();
byte[] x = ecPoint.getAffineX().toByteArray();
byte[] y = ecPoint.getAffineY().toByteArray();
unique = new ECCUnique(x, y);
}
return new TPMTPublic(type, nameAlg, objectAttributes, authPolicy, parameters, unique);
}
public static ECCurve convertCurve(
EllipticCurve ec)
{
ECField field = ec.getField();
BigInteger a = ec.getA();
BigInteger b = ec.getB();
if (field instanceof ECFieldFp)
{
ECCurve.Fp curve = new ECCurve.Fp(((ECFieldFp)field).getP(), a, b);
if (customCurves.containsKey(curve))
{
return (ECCurve)customCurves.get(curve);
}
return curve;
}
else
{
ECFieldF2m fieldF2m = (ECFieldF2m)field;
int m = fieldF2m.getM();
int ks[] = ECUtil.convertMidTerms(fieldF2m.getMidTermsOfReductionPolynomial());
return new ECCurve.F2m(m, ks[0], ks[1], ks[2], a, b);
}
}
public static ECParameterSpec getECParameterSpec() {
BigInteger n = new BigInteger(
"FFFFFFFE" + "FFFFFFFF" + "FFFFFFFF" + "FFFFFFFF" + "7203DF6B" + "21C6052B" + "53BBF409" + "39D54123", 16);
BigInteger p = new BigInteger(
"FFFFFFFE" + "FFFFFFFF" + "FFFFFFFF" + "FFFFFFFF" + "FFFFFFFF" + "00000000" + "FFFFFFFF" + "FFFFFFFF", 16);
BigInteger a = new BigInteger(
"FFFFFFFE" + "FFFFFFFF" + "FFFFFFFF" + "FFFFFFFF" + "FFFFFFFF" + "00000000" + "FFFFFFFF" + "FFFFFFFC", 16);
BigInteger b = new BigInteger(
"28E9FA9E" + "9D9F5E34" + "4D5A9E4B" + "CF6509A7" + "F39789F5" + "15AB8F92" + "DDBCBD41" + "4D940E93", 16);
BigInteger gx = new BigInteger(
"32C4AE2C" + "1F198119" + "5F990446" + "6A39C994" + "8FE30BBF" + "F2660BE1" + "715A4589" + "334C74C7", 16);
BigInteger gy = new BigInteger(
"BC3736A2" + "F4F6779C" + "59BDCEE3" + "6B692153" + "D0A9877C" + "C62A4740" + "02DF32E5" + "2139F0A0", 16);
EllipticCurve ellipticCurve = new EllipticCurve(new ECFieldFp(p), a, b);
return new ECParameterSpec(ellipticCurve, new ECPoint(gx, gy), n, 1);
}
public static Optional<ECOperations> forParameters(ECParameterSpec params) {
EllipticCurve curve = params.getCurve();
if (!(curve.getField() instanceof ECFieldFp)) {
return Optional.empty();
}
ECFieldFp primeField = (ECFieldFp) curve.getField();
BigInteger three = BigInteger.valueOf(3);
if (!primeField.getP().subtract(curve.getA()).equals(three)) {
return Optional.empty();
}
IntegerFieldModuloP field = fields.get(primeField.getP());
if (field == null) {
return Optional.empty();
}
IntegerFieldModuloP orderField = orderFields.get(params.getOrder());
if (orderField == null) {
return Optional.empty();
}
ImmutableIntegerModuloP b = field.getElement(curve.getB());
ECOperations ecOps = new ECOperations(b, orderField);
return Optional.of(ecOps);
}
private static ECPoint decodePoint(byte[] data, EllipticCurve curve)
throws IOException {
if ((data.length == 0) || (data[0] != 4)) {
throw new IOException("Only uncompressed point format " +
"supported");
}
// Per ANSI X9.62, an encoded point is a 1 byte type followed by
// ceiling(log base 2 field-size / 8) bytes of x and the same of y.
int n = (data.length - 1) / 2;
if (n != ((curve.getField().getFieldSize() + 7) >> 3)) {
throw new IOException("Point does not match field size");
}
byte[] xb = Arrays.copyOfRange(data, 1, 1 + n);
byte[] yb = Arrays.copyOfRange(data, n + 1, n + 1 + n);
return new ECPoint(new BigInteger(1, xb), new BigInteger(1, yb));
}
public BCECGOST3410PublicKey(
org.ripple.bouncycastle.jce.spec.ECPublicKeySpec spec)
{
this.q = spec.getQ();
if (spec.getParams() != null) // can be null if implictlyCa
{
ECCurve curve = spec.getParams().getCurve();
EllipticCurve ellipticCurve = EC5Util.convertCurve(curve, spec.getParams().getSeed());
this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
}
else
{
if (q.getCurve() == null)
{
org.ripple.bouncycastle.jce.spec.ECParameterSpec s = BouncyCastleProvider.CONFIGURATION.getEcImplicitlyCa();
q = s.getCurve().createPoint(q.getAffineXCoord().toBigInteger(), q.getAffineYCoord().toBigInteger());
}
this.ecSpec = null;
}
}
public JCEECPrivateKey(
String algorithm,
org.ripple.bouncycastle.jce.spec.ECPrivateKeySpec spec)
{
this.algorithm = algorithm;
this.d = spec.getD();
if (spec.getParams() != null) // can be null if implicitlyCA
{
ECCurve curve = spec.getParams().getCurve();
EllipticCurve ellipticCurve;
ellipticCurve = EC5Util.convertCurve(curve, spec.getParams().getSeed());
this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
}
else
{
this.ecSpec = null;
}
}
private static ECPoint decodePoint(byte[] data, EllipticCurve curve)
throws IOException {
if ((data.length == 0) || (data[0] != 4)) {
throw new IOException("Only uncompressed point format " +
"supported");
}
// Per ANSI X9.62, an encoded point is a 1 byte type followed by
// ceiling(log base 2 field-size / 8) bytes of x and the same of y.
int n = (data.length - 1) / 2;
if (n != ((curve.getField().getFieldSize() + 7) >> 3)) {
throw new IOException("Point does not match field size");
}
byte[] xb = Arrays.copyOfRange(data, 1, 1 + n);
byte[] yb = Arrays.copyOfRange(data, n + 1, n + 1 + n);
return new ECPoint(new BigInteger(1, xb), new BigInteger(1, yb));
}
public BCECGOST3410PublicKey(
String algorithm,
ECPublicKeyParameters params,
ECParameterSpec spec)
{
ECDomainParameters dp = params.getParameters();
this.algorithm = algorithm;
this.q = params.getQ();
if (spec == null)
{
EllipticCurve ellipticCurve = EC5Util.convertCurve(dp.getCurve(), dp.getSeed());
this.ecSpec = createSpec(ellipticCurve, dp);
}
else
{
this.ecSpec = spec;
}
}
/**
* Returns this key as ECPublicKeySpec or null if the key cannot be represented as
* ECPublicKeySpec. The later happens for example if the order of cofactor are not positive.
*/
public ECPublicKeySpec getSpec() {
try {
ECFieldFp fp = new ECFieldFp(p);
EllipticCurve curve = new EllipticCurve(fp, a, b);
ECPoint g = new ECPoint(gx, gy);
// ECParameterSpec requires that the cofactor h is specified.
if (h == null) {
return null;
}
ECParameterSpec params = new ECParameterSpec(curve, g, n, h);
ECPoint pubPoint = new ECPoint(pubx, puby);
ECPublicKeySpec pub = new ECPublicKeySpec(pubPoint, params);
return pub;
} catch (Exception ex) {
System.out.println(comment + " throws " + ex.toString());
return null;
}
}
public static ECParameterSpec getNistCurveSpec(
String decimalP, String decimalN, String hexB, String hexGX, String hexGY) {
final BigInteger p = new BigInteger(decimalP);
final BigInteger n = new BigInteger(decimalN);
final BigInteger three = new BigInteger("3");
final BigInteger a = p.subtract(three);
final BigInteger b = new BigInteger(hexB, 16);
final BigInteger gx = new BigInteger(hexGX, 16);
final BigInteger gy = new BigInteger(hexGY, 16);
final int h = 1;
ECFieldFp fp = new ECFieldFp(p);
java.security.spec.EllipticCurve curveSpec = new java.security.spec.EllipticCurve(fp, a, b);
ECPoint g = new ECPoint(gx, gy);
ECParameterSpec ecSpec = new ECParameterSpec(curveSpec, g, n, h);
return ecSpec;
}
public static ECParameterSpec getBrainpoolP224r1Params() {
// name = "brainpoolP224r1",
// oid = '2b2403030208010105',
// ref = "RFC 5639",
BigInteger p = new BigInteger("D7C134AA264366862A18302575D1D787B09F075797DA89F57EC8C0FF", 16);
BigInteger a = new BigInteger("68A5E62CA9CE6C1C299803A6C1530B514E182AD8B0042A59CAD29F43", 16);
BigInteger b = new BigInteger("2580F63CCFE44138870713B1A92369E33E2135D266DBB372386C400B", 16);
BigInteger x = new BigInteger("0D9029AD2C7E5CF4340823B2A87DC68C9E4CE3174C1E6EFDEE12C07D", 16);
BigInteger y = new BigInteger("58AA56F772C0726F24C6B89E4ECDAC24354B9E99CAA3F6D3761402CD", 16);
BigInteger n = new BigInteger("D7C134AA264366862A18302575D0FB98D116BC4B6DDEBCA3A5A7939F", 16);
final int h = 1;
ECFieldFp fp = new ECFieldFp(p);
EllipticCurve curve = new EllipticCurve(fp, a, b);
ECPoint g = new ECPoint(x, y);
return new ECParameterSpec(curve, g, n, h);
}
public static ECParameterSpec getBrainpoolP256r1Params() {
BigInteger p =
new BigInteger("A9FB57DBA1EEA9BC3E660A909D838D726E3BF623D52620282013481D1F6E5377", 16);
BigInteger a =
new BigInteger("7D5A0975FC2C3057EEF67530417AFFE7FB8055C126DC5C6CE94A4B44F330B5D9", 16);
BigInteger b =
new BigInteger("26DC5C6CE94A4B44F330B5D9BBD77CBF958416295CF7E1CE6BCCDC18FF8C07B6", 16);
BigInteger x =
new BigInteger("8BD2AEB9CB7E57CB2C4B482FFC81B7AFB9DE27E1E3BD23C23A4453BD9ACE3262", 16);
BigInteger y =
new BigInteger("547EF835C3DAC4FD97F8461A14611DC9C27745132DED8E545C1D54C72F046997", 16);
BigInteger n =
new BigInteger("A9FB57DBA1EEA9BC3E660A909D838D718C397AA3B561A6F7901E0E82974856A7", 16);
final int h = 1;
ECFieldFp fp = new ECFieldFp(p);
EllipticCurve curve = new EllipticCurve(fp, a, b);
ECPoint g = new ECPoint(x, y);
return new ECParameterSpec(curve, g, n, h);
}
/**
* Checks that a point is on a given elliptic curve. This method implements the partial public key
* validation routine from Section 5.6.2.6 of NIST SP 800-56A
* http://csrc.nist.gov/publications/nistpubs/800-56A/SP800-56A_Revision1_Mar08-2007.pdf A partial
* public key validation is sufficient for curves with cofactor 1. See Section B.3 of
* http://www.nsa.gov/ia/_files/SuiteB_Implementer_G-113808.pdf The point validations above are
* taken from recommendations for ECDH, because parameter checks in ECDH are much more important
* than for the case of ECDSA. Performing this test for ECDSA keys is mainly a sanity check.
*
* @param point the point that needs verification
* @param ec the elliptic curve. This must be a curve over a prime order field.
* @throws GeneralSecurityException if the field is binary or if the point is not on the curve.
*/
public static void checkPointOnCurve(ECPoint point, EllipticCurve ec)
throws GeneralSecurityException {
BigInteger p = getModulus(ec);
BigInteger x = point.getAffineX();
BigInteger y = point.getAffineY();
if (x == null || y == null) {
throw new GeneralSecurityException("point is at infinity");
}
// Check 0 <= x < p and 0 <= y < p.
if (x.signum() == -1 || x.compareTo(p) != -1) {
throw new GeneralSecurityException("x is out of range");
}
if (y.signum() == -1 || y.compareTo(p) != -1) {
throw new GeneralSecurityException("y is out of range");
}
// Check y^2 == x^3 + a x + b (mod p)
BigInteger lhs = y.multiply(y).mod(p);
BigInteger rhs = x.multiply(x).add(ec.getA()).multiply(x).add(ec.getB()).mod(p);
if (!lhs.equals(rhs)) {
throw new GeneralSecurityException("Point is not on curve");
}
}
/**
* Decompress a point
*
* @param x The x-coordinate of the point
* @param bit0 true if the least significant bit of y is set.
* @param ecParams contains the curve of the point. This must be over a prime order field.
*/
public static ECPoint getPoint(BigInteger x, boolean bit0, ECParameterSpec ecParams)
throws GeneralSecurityException {
EllipticCurve ec = ecParams.getCurve();
ECField field = ec.getField();
if (!(field instanceof ECFieldFp)) {
throw new GeneralSecurityException("Only curves over prime order fields are supported");
}
BigInteger p = ((java.security.spec.ECFieldFp) field).getP();
if (x.compareTo(BigInteger.ZERO) == -1 || x.compareTo(p) != -1) {
throw new GeneralSecurityException("x is out of range");
}
// Compute rhs == x^3 + a x + b (mod p)
BigInteger rhs = x.multiply(x).add(ec.getA()).multiply(x).add(ec.getB()).mod(p);
BigInteger y = modSqrt(rhs, p);
if (bit0 != y.testBit(0)) {
y = p.subtract(y).mod(p);
}
return new ECPoint(x, y);
}
public static Optional<ECOperations> forParameters(ECParameterSpec params) {
EllipticCurve curve = params.getCurve();
if (!(curve.getField() instanceof ECFieldFp)) {
return Optional.empty();
}
ECFieldFp primeField = (ECFieldFp) curve.getField();
BigInteger three = BigInteger.valueOf(3);
if (!primeField.getP().subtract(curve.getA()).equals(three)) {
return Optional.empty();
}
IntegerFieldModuloP field = fields.get(primeField.getP());
if (field == null) {
return Optional.empty();
}
IntegerFieldModuloP orderField = orderFields.get(params.getOrder());
if (orderField == null) {
return Optional.empty();
}
ImmutableIntegerModuloP b = field.getElement(curve.getB());
ECOperations ecOps = new ECOperations(b, orderField);
return Optional.of(ecOps);
}
public JCEECPrivateKey(
String algorithm,
org.ripple.bouncycastle.jce.spec.ECPrivateKeySpec spec)
{
this.algorithm = algorithm;
this.d = spec.getD();
if (spec.getParams() != null) // can be null if implicitlyCA
{
ECCurve curve = spec.getParams().getCurve();
EllipticCurve ellipticCurve;
ellipticCurve = EC5Util.convertCurve(curve, spec.getParams().getSeed());
this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
}
else
{
this.ecSpec = null;
}
}
private static ECPoint decodePoint(byte[] data, EllipticCurve curve)
throws IOException {
if ((data.length == 0) || (data[0] != 4)) {
throw new IOException("Only uncompressed point format " +
"supported");
}
// Per ANSI X9.62, an encoded point is a 1 byte type followed by
// ceiling(log base 2 field-size / 8) bytes of x and the same of y.
int n = (data.length - 1) / 2;
if (n != ((curve.getField().getFieldSize() + 7) >> 3)) {
throw new IOException("Point does not match field size");
}
byte[] xb = Arrays.copyOfRange(data, 1, 1 + n);
byte[] yb = Arrays.copyOfRange(data, n + 1, n + 1 + n);
return new ECPoint(new BigInteger(1, xb), new BigInteger(1, yb));
}
public BCECPublicKey(
String algorithm,
ECPublicKeyParameters params,
ECParameterSpec spec,
ProviderConfiguration configuration)
{
ECDomainParameters dp = params.getParameters();
this.algorithm = algorithm;
this.q = params.getQ();
if (spec == null)
{
EllipticCurve ellipticCurve = EC5Util.convertCurve(dp.getCurve(), dp.getSeed());
this.ecSpec = createSpec(ellipticCurve, dp);
}
else
{
this.ecSpec = spec;
}
this.configuration = configuration;
}
public BCECGOST3410PrivateKey(
org.ripple.bouncycastle.jce.spec.ECPrivateKeySpec spec)
{
this.d = spec.getD();
if (spec.getParams() != null) // can be null if implicitlyCA
{
ECCurve curve = spec.getParams().getCurve();
EllipticCurve ellipticCurve;
ellipticCurve = EC5Util.convertCurve(curve, spec.getParams().getSeed());
this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
}
else
{
this.ecSpec = null;
}
}
public JCEECPublicKey(
String algorithm,
org.ripple.bouncycastle.jce.spec.ECPublicKeySpec spec)
{
this.algorithm = algorithm;
this.q = spec.getQ();
if (spec.getParams() != null) // can be null if implictlyCa
{
ECCurve curve = spec.getParams().getCurve();
EllipticCurve ellipticCurve = EC5Util.convertCurve(curve, spec.getParams().getSeed());
this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
}
else
{
if (q.getCurve() == null)
{
org.ripple.bouncycastle.jce.spec.ECParameterSpec s = BouncyCastleProvider.CONFIGURATION.getEcImplicitlyCa();
q = s.getCurve().createPoint(q.getAffineXCoord().toBigInteger(), q.getAffineYCoord().toBigInteger(), false);
}
this.ecSpec = null;
}
}
public BCECGOST3410PrivateKey(
org.ripple.bouncycastle.jce.spec.ECPrivateKeySpec spec)
{
this.d = spec.getD();
if (spec.getParams() != null) // can be null if implicitlyCA
{
ECCurve curve = spec.getParams().getCurve();
EllipticCurve ellipticCurve;
ellipticCurve = EC5Util.convertCurve(curve, spec.getParams().getSeed());
this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
}
else
{
this.ecSpec = null;
}
}
public BCECPrivateKey(
String algorithm,
org.ripple.bouncycastle.jce.spec.ECPrivateKeySpec spec,
ProviderConfiguration configuration)
{
this.algorithm = algorithm;
this.d = spec.getD();
if (spec.getParams() != null) // can be null if implicitlyCA
{
ECCurve curve = spec.getParams().getCurve();
EllipticCurve ellipticCurve;
ellipticCurve = EC5Util.convertCurve(curve, spec.getParams().getSeed());
this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
}
else
{
this.ecSpec = null;
}
this.configuration = configuration;
}
public BCECPrivateKey(
String algorithm,
org.ripple.bouncycastle.jce.spec.ECPrivateKeySpec spec,
ProviderConfiguration configuration)
{
this.algorithm = algorithm;
this.d = spec.getD();
if (spec.getParams() != null) // can be null if implicitlyCA
{
ECCurve curve = spec.getParams().getCurve();
EllipticCurve ellipticCurve;
ellipticCurve = EC5Util.convertCurve(curve, spec.getParams().getSeed());
this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
}
else
{
this.ecSpec = null;
}
this.configuration = configuration;
}
public BCDSTU4145PublicKey(
org.ripple.bouncycastle.jce.spec.ECPublicKeySpec spec)
{
this.q = spec.getQ();
if (spec.getParams() != null) // can be null if implictlyCa
{
ECCurve curve = spec.getParams().getCurve();
EllipticCurve ellipticCurve = EC5Util.convertCurve(curve, spec.getParams().getSeed());
this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
}
else
{
if (q.getCurve() == null)
{
org.ripple.bouncycastle.jce.spec.ECParameterSpec s = BouncyCastleProvider.CONFIGURATION.getEcImplicitlyCa();
q = s.getCurve().createPoint(q.getAffineXCoord().toBigInteger(), q.getAffineYCoord().toBigInteger());
}
this.ecSpec = null;
}
}
void getMethods() throws ClassNotFoundException, NoSuchMethodException {
Class c = Class.forName("sun.security.ec.ECParameters");
Class[] params = new Class[] { ECPoint.class, EllipticCurve.class };
encodePoint = c.getMethod("encodePoint", params);
params = new Class[] { ECParameterSpec.class };
getCurveName = c.getMethod("getCurveName", params);
params = new Class[] { byte[].class, EllipticCurve.class };
decodePoint = c.getMethod("decodePoint", params);
c = Class.forName("sun.security.ec.NamedCurve");
params = new Class[] { String.class };
getECParameterSpec = c.getMethod("getECParameterSpec", params);
}
void getMethods() throws ClassNotFoundException, NoSuchMethodException {
Class c = Class.forName("sun.security.ec.ECParameters");
Class[] params = new Class[] { ECPoint.class, EllipticCurve.class };
encodePoint = c.getMethod("encodePoint", params);
params = new Class[] { ECParameterSpec.class };
getCurveName = c.getMethod("getCurveName", params);
params = new Class[] { byte[].class, EllipticCurve.class };
decodePoint = c.getMethod("decodePoint", params);
c = Class.forName("sun.security.ec.NamedCurve");
params = new Class[] { String.class };
getECParameterSpec = c.getMethod("getECParameterSpec", params);
}