| /* |
| * 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 defines an elliptic curve (EC) prime |
| * finite field. |
| * |
| * @see ECField |
| * |
| * @author Valerie Peng |
| * |
| * @since 1.5 |
| */ |
| public class ECFieldFp implements ECField { |
| |
| private BigInteger p; |
| |
| /** |
| * Creates an elliptic curve prime finite field |
| * with the specified prime {@code p}. |
| * @param p the prime. |
| * @exception NullPointerException if {@code p} is null. |
| * @exception IllegalArgumentException if {@code p} |
| * is not positive. |
| */ |
| public ECFieldFp(BigInteger p) { |
| if (p.signum() != 1) { |
| throw new IllegalArgumentException("p is not positive"); |
| } |
| this.p = p; |
| } |
| |
| /** |
| * Returns the field size in bits which is size of prime p |
| * for this prime finite field. |
| * @return the field size in bits. |
| */ |
| public int getFieldSize() { |
| return p.bitLength(); |
| }; |
| |
| /** |
| * Returns the prime {@code p} of this prime finite field. |
| * @return the prime. |
| */ |
| public BigInteger getP() { |
| return p; |
| } |
| |
| /** |
| * Compares this prime finite field for equality with the |
| * specified object. |
| * @param obj the object to be compared. |
| * @return true if {@code obj} is an instance |
| * of ECFieldFp and the prime value match, false otherwise. |
| */ |
| public boolean equals(Object obj) { |
| if (this == obj) return true; |
| if (obj instanceof ECFieldFp) { |
| return (p.equals(((ECFieldFp)obj).p)); |
| } |
| return false; |
| } |
| |
| /** |
| * Returns a hash code value for this prime finite field. |
| * @return a hash code value. |
| */ |
| public int hashCode() { |
| return p.hashCode(); |
| } |
| } |