1 /*
2 * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
28 import java.util.Arrays;
29
30 /**
31 * This immutable class defines an elliptic curve (EC) prime
32 * finite field.
33 *
34 * @see ECField
35 *
36 * @author Valerie Peng
37 *
38 * @since 1.5
39 */
40 public class ECFieldFp implements ECField {
41
42 private BigInteger p;
43
44 /**
45 * Creates an elliptic curve prime finite field
46 * with the specified prime {@code p}.
47 * @param p the prime.
48 * @exception NullPointerException if {@code p} is null.
49 * @exception IllegalArgumentException if {@code p}
50 * is not positive.
51 */
52 public ECFieldFp(BigInteger p) {
53 if (p.signum() != 1) {
54 throw new IllegalArgumentException("p is not positive");
55 }
56 this.p = p;
57 }
58
59 /**
60 * Returns the field size in bits which is size of prime p
61 * for this prime finite field.
62 * @return the field size in bits.
63 */
64 public int getFieldSize() {
65 return p.bitLength();
66 };
67
68 /**
69 * Returns the prime {@code p} of this prime finite field.
|
1 /*
2 * Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
28 import java.util.Arrays;
29
30 /**
31 * This immutable class defines an elliptic curve (EC) prime
32 * finite field.
33 *
34 * @see ECField
35 *
36 * @author Valerie Peng
37 *
38 * @since 1.5
39 */
40 public class ECFieldFp implements ECField {
41
42 private BigInteger p;
43
44 /**
45 * Creates an elliptic curve prime finite field
46 * with the specified prime {@code p}.
47 * @param p the prime.
48 * @throws NullPointerException if {@code p} is null.
49 * @throws IllegalArgumentException if {@code p}
50 * is not positive.
51 */
52 public ECFieldFp(BigInteger p) {
53 if (p.signum() != 1) {
54 throw new IllegalArgumentException("p is not positive");
55 }
56 this.p = p;
57 }
58
59 /**
60 * Returns the field size in bits which is size of prime p
61 * for this prime finite field.
62 * @return the field size in bits.
63 */
64 public int getFieldSize() {
65 return p.bitLength();
66 };
67
68 /**
69 * Returns the prime {@code p} of this prime finite field.
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