--- /dev/null	2018-02-28 15:06:04.760000000 -0500
+++ new/src/jdk.crypto.ec/share/classes/sun/security/ec/XDHPrivateKeyImpl.java	2018-03-09 11:19:31.710014000 -0500
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+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());
+    }
+}
+