import org.bouncycastle.pqc.math.linearalgebra.GoppaCode; //导入依赖的package包/类
public AsymmetricCipherKeyPair generateKeyPair()
{

    if (!initialized)
    {
        initializeDefault();
    }

    // finite field GF(2^m)
    GF2mField field = new GF2mField(m, fieldPoly);

    // irreducible Goppa polynomial
    PolynomialGF2mSmallM gp = new PolynomialGF2mSmallM(field, t,
        PolynomialGF2mSmallM.RANDOM_IRREDUCIBLE_POLYNOMIAL, random);
    PolynomialRingGF2m ring = new PolynomialRingGF2m(field, gp);

    // matrix for computing square roots in (GF(2^m))^t
    PolynomialGF2mSmallM[] qInv = ring.getSquareRootMatrix();

    // generate canonical check matrix
    GF2Matrix h = GoppaCode.createCanonicalCheckMatrix(field, gp);

    // compute short systematic form of check matrix
    MaMaPe mmp = GoppaCode.computeSystematicForm(h, random);
    GF2Matrix shortH = mmp.getSecondMatrix();
    Permutation p = mmp.getPermutation();

    // compute short systematic form of generator matrix
    GF2Matrix shortG = (GF2Matrix)shortH.computeTranspose();

    // obtain number of rows of G (= dimension of the code)
    int k = shortG.getNumRows();

    // generate keys
    McElieceCCA2PublicKeyParameters pubKey = new McElieceCCA2PublicKeyParameters(OID, n, t, shortG, mcElieceCCA2Params.getParameters());
    McElieceCCA2PrivateKeyParameters privKey = new McElieceCCA2PrivateKeyParameters(OID, n, k,
        field, gp, p, h, qInv, mcElieceCCA2Params.getParameters());

    // return key pair
    return new AsymmetricCipherKeyPair(pubKey, privKey);
}