Signature sign=Signature.getInstance(Constants.SIGN_EL_ALG_2012_256);
sign.initSign(k); //Инициализирую подпись ключом моего личного сертификата
sign.update(b);   //Ввожу сканоникализированные данные
return(Base64.encode(sign.sign()));

            CAdESSignature cadesSignature = new CAdESSignature( true );
            Collection<X509CertificateHolder> holderList = new ArrayList<X509CertificateHolder>();
            
            for (X509Certificate cert1 : chain) 
                    {
                        holderList.add(new X509CertificateHolder(cert1.getEncoded()));
                    } 
                    cadesSignature.setCertificateStore(new CollectionStore(holderList));
            
            cadesSignature.addSigner(JCP.PROVIDER_NAME,getDigestOid(k),getPublicKeyOid(k),k, chain, CAdESType.CAdES_T, /*"http://www.cryptopro.ru/tsp/"*/Configuration.TSA_DEFAULT_ADDRESS, false );

    public String sign(String value) throws Exception
    {
        byte[] b=null;
        JCPStoreApi jcpStoreApi=null;

        try
        {
            //Каноникализация
            b=Canonicalizer.getInstance(Canonicalizer.ALGO_ID_C14N_EXCL_OMIT_COMMENTS).canonicalize(value.getBytes());
            
            //Получение сведений о сертификате
            jcpStoreApi=new JCPStoreApi(); 
            PrivateKey k=jcpStoreApi.loadKey("le-4145024e-1dd0-4ce2-88c5-d515010385d9 - Copy","1234");
     
            if(k==null) return(null);

            //Подписание
            Signature sign=Signature.getInstance(Constants.SIGN_EL_ALG_2012_256,JCP.PROVIDER_NAME);
            sign.initSign(k);
            sign.update(b);
            
            byte[] s=sign.sign();
            
            //Проверка
            Signature sign2=Signature.getInstance(Constants.SIGN_EL_ALG_2012_256,JCP.PROVIDER_NAME);
            //sign2.initVerify(jcpStoreApi.certificate);
            //sign2.initVerify(jcpStoreApi.x509Certificate);
            sign2.initVerify(jcpStoreApi.x509Certificate.getPublicKey());
            sign2.update(b);
            System.out.println(sign2.verify(s));
            
            return(Base64.encode(s));
        }
        finally
        {
            b=null;
            jcpStoreApi=null;
        }
    }