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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

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 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

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package sun.security.ec;

import java.security.interfaces.XECPrivateKey;

import java.util.Optional;

import java.security.InvalidKeyException;

import java.security.PrivateKey;

import java.security.spec.AlgorithmParameterSpec;

import java.security.spec.NamedParameterSpec;

import sun.security.pkcs.PKCS8Key;

import sun.security.x509.AlgorithmId;

public final class XDHPrivateKeyImpl extends PKCS8Key implements XECPrivateKey {

    private static final long serialVersionUID = 1L;

    private AlgorithmParameterSpec paramSpec;

    XDHPrivateKeyImpl(XECParameters params, byte[] k)

        throws InvalidKeyException {

        this.paramSpec = new NamedParameterSpec(params.getName());

        this.algid = new AlgorithmId(params.getOid());

        this.key = k.clone();

        checkLength(params);

    }

    XDHPrivateKeyImpl(byte[] encoded) throws InvalidKeyException {

        decode(encoded);

        XECParameters params = XECParameters.get(

            InvalidKeyException::new, algid);

        paramSpec = new NamedParameterSpec(params.getName());

        checkLength(params);

    }

    void checkLength(XECParameters params) throws InvalidKeyException {

        if (params.getBytes() != this.key.length) {

            throw new InvalidKeyException(

                "key length must be " + params.getBytes());

        }

    }

    public byte[] getK() {

        return key.clone();

    }

    @Override

    public String getAlgorithm() {

        return "XDH";

    }

    @Override

    public AlgorithmParameterSpec getParams() {

        return paramSpec;

    }

    @Override

    public Optional<byte[]> getScalar() {

        return Optional.of(getK());

    }

}