8187443: Forest Consolidation: Move files to unified layout

Reviewed-by: darcy, ihse

src/java.base/share/classes/java/security/spec/EllipticCurve.java

@@ -0,0 +1,196 @@
+/*
+ * Copyright (c) 2003, 2013, 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 java.security.spec;
+
+import java.math.BigInteger;
+import java.util.Arrays;
+
+/**
+ * This immutable class holds the necessary values needed to represent
+ * an elliptic curve.
+ *
+ * @see ECField
+ * @see ECFieldFp
+ * @see ECFieldF2m
+ *
+ * @author Valerie Peng
+ *
+ * @since 1.5
+ */
+public class EllipticCurve {
+
+    private final ECField field;
+    private final BigInteger a;
+    private final BigInteger b;
+    private final byte[] seed;
+
+    // Check coefficient c is a valid element in ECField field.
+    private static void checkValidity(ECField field, BigInteger c,
+        String cName) {
+        // can only perform check if field is ECFieldFp or ECFieldF2m.
+        if (field instanceof ECFieldFp) {
+            BigInteger p = ((ECFieldFp)field).getP();
+            if (p.compareTo(c) != 1) {
+                throw new IllegalArgumentException(cName + " is too large");
+            } else if (c.signum() < 0) {
+                throw new IllegalArgumentException(cName + " is negative");
+            }
+        } else if (field instanceof ECFieldF2m) {
+            int m = ((ECFieldF2m)field).getM();
+            if (c.bitLength() > m) {
+                throw new IllegalArgumentException(cName + " is too large");
+            }
+        }
+    }
+
+    /**
+     * Creates an elliptic curve with the specified elliptic field
+     * {@code field} and the coefficients {@code a} and
+     * {@code b}.
+     * @param field the finite field that this elliptic curve is over.
+     * @param a the first coefficient of this elliptic curve.
+     * @param b the second coefficient of this elliptic curve.
+     * @exception NullPointerException if {@code field},
+     * {@code a}, or {@code b} is null.
+     * @exception IllegalArgumentException if {@code a}
+     * or {@code b} is not null and not in {@code field}.
+     */
+    public EllipticCurve(ECField field, BigInteger a,
+                         BigInteger b) {
+        this(field, a, b, null);
+    }
+
+    /**
+     * Creates an elliptic curve with the specified elliptic field
+     * {@code field}, the coefficients {@code a} and
+     * {@code b}, and the {@code seed} used for curve generation.
+     * @param field the finite field that this elliptic curve is over.
+     * @param a the first coefficient of this elliptic curve.
+     * @param b the second coefficient of this elliptic curve.
+     * @param seed the bytes used during curve generation for later
+     * validation. Contents of this array are copied to protect against
+     * subsequent modification.
+     * @exception NullPointerException if {@code field},
+     * {@code a}, or {@code b} is null.
+     * @exception IllegalArgumentException if {@code a}
+     * or {@code b} is not null and not in {@code field}.
+     */
+    public EllipticCurve(ECField field, BigInteger a,
+                         BigInteger b, byte[] seed) {
+        if (field == null) {
+            throw new NullPointerException("field is null");
+        }
+        if (a == null) {
+            throw new NullPointerException("first coefficient is null");
+        }
+        if (b == null) {
+            throw new NullPointerException("second coefficient is null");
+        }
+        checkValidity(field, a, "first coefficient");
+        checkValidity(field, b, "second coefficient");
+        this.field = field;
+        this.a = a;
+        this.b = b;
+        if (seed != null) {
+            this.seed = seed.clone();
+        } else {
+            this.seed = null;
+        }
+    }
+
+    /**
+     * Returns the finite field {@code field} that this
+     * elliptic curve is over.
+     * @return the field {@code field} that this curve
+     * is over.
+     */
+    public ECField getField() {
+        return field;
+    }
+
+    /**
+     * Returns the first coefficient {@code a} of the
+     * elliptic curve.
+     * @return the first coefficient {@code a}.
+     */
+    public BigInteger getA() {
+        return a;
+    }
+
+    /**
+     * Returns the second coefficient {@code b} of the
+     * elliptic curve.
+     * @return the second coefficient {@code b}.
+     */
+    public BigInteger getB() {
+        return b;
+    }
+
+    /**
+     * Returns the seeding bytes {@code seed} used
+     * during curve generation. May be null if not specified.
+     * @return the seeding bytes {@code seed}. A new
+     * array is returned each time this method is called.
+     */
+    public byte[] getSeed() {
+        if (seed == null) return null;
+        else return seed.clone();
+    }
+
+    /**
+     * Compares this elliptic curve for equality with the
+     * specified object.
+     * @param obj the object to be compared.
+     * @return true if {@code obj} is an instance of
+     * EllipticCurve and the field, A, and B match, false otherwise.
+     */
+    public boolean equals(Object obj) {
+        if (this == obj) return true;
+        if (obj instanceof EllipticCurve) {
+            EllipticCurve curve = (EllipticCurve) obj;
+            if ((field.equals(curve.field)) &&
+                (a.equals(curve.a)) &&
+                (b.equals(curve.b))) {
+                    return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Returns a hash code value for this elliptic curve.
+     * @return a hash code value computed from the hash codes of the field, A,
+     * and B, as follows:
+     * <pre>{@code
+     *     (field.hashCode() << 6) + (a.hashCode() << 4) + (b.hashCode() << 2)
+     * }</pre>
+     */
+    public int hashCode() {
+        return (field.hashCode() << 6 +
+            (a.hashCode() << 4) +
+            (b.hashCode() << 2));
+    }
+}