Showing the changes to java/pkg/java/security/spec/ECPoint.java (1 of 18352 files). Show all
Unified · Split
| @@ -0,0 +1,114 @@ | |||
| 1 | /* | ||
| 2 | * Copyright (c) 2003, 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 | ||
| 23 | * questions. | ||
| 24 | */ | ||
| 25 | package java.security.spec; | ||
| 26 | |||
| 27 | import java.math.BigInteger; | ||
| 28 | |||
| 29 | /** | ||
| 30 | * This immutable class represents a point on an elliptic curve (EC) | ||
| 31 | * in affine coordinates. Other coordinate systems can | ||
| 32 | * extend this class to represent this point in other | ||
| 33 | * coordinates. | ||
| 34 | * | ||
| 35 | * @author Valerie Peng | ||
| 36 | * | ||
| 37 | * @since 1.5 | ||
| 38 | */ | ||
| 39 | public class ECPoint { | ||
| 40 | |||
| 41 | private final BigInteger x; | ||
| 42 | private final BigInteger y; | ||
| 43 | |||
| 44 | /** | ||
| 45 | * This defines the point at infinity. | ||
| 46 | */ | ||
| 47 | public static final ECPoint POINT_INFINITY = new ECPoint(); | ||
| 48 | |||
| 49 | // private constructor for constructing point at infinity | ||
| 50 | private ECPoint() { | ||
| 51 | this.x = null; | ||
| 52 | this.y = null; | ||
| 53 | } | ||
| 54 | |||
| 55 | /** | ||
| 56 | * Creates an ECPoint from the specified affine x-coordinate | ||
| 57 | * <code>x</code> and affine y-coordinate <code>y</code>. | ||
| 58 | * @param x the affine x-coordinate. | ||
| 59 | * @param y the affine y-coordinate. | ||
| 60 | * @exception NullPointerException if <code>x</code> or | ||
| 61 | * <code>y</code> is null. | ||
| 62 | */ | ||
| 63 | public ECPoint(BigInteger x, BigInteger y) { | ||
| 64 | if ((x==null) || (y==null)) { | ||
| 65 | throw new NullPointerException("affine coordinate x or y is null"); | ||
| 66 | } | ||
| 67 | this.x = x; | ||
| 68 | this.y = y; | ||
| 69 | } | ||
| 70 | |||
| 71 | /** | ||
| 72 | * Returns the affine x-coordinate <code>x</code>. | ||
| 73 | * Note: POINT_INFINITY has a null affine x-coordinate. | ||
| 74 | * @return the affine x-coordinate. | ||
| 75 | */ | ||
| 76 | public BigInteger getAffineX() { | ||
| 77 | return x; | ||
| 78 | } | ||
| 79 | |||
| 80 | /** | ||
| 81 | * Returns the affine y-coordinate <code>y</code>. | ||
| 82 | * Note: POINT_INFINITY has a null affine y-coordinate. | ||
| 83 | * @return the affine y-coordinate. | ||
| 84 | */ | ||
| 85 | public BigInteger getAffineY() { | ||
| 86 | return y; | ||
| 87 | } | ||
| 88 | |||
| 89 | /** | ||
| 90 | * Compares this elliptic curve point for equality with | ||
| 91 | * the specified object. | ||
| 92 | * @param obj the object to be compared. | ||
| 93 | * @return true if <code>obj</code> is an instance of | ||
| 94 | * ECPoint and the affine coordinates match, false otherwise. | ||
| 95 | */ | ||
| 96 | public boolean equals(Object obj) { | ||
| 97 | if (this == obj) return true; | ||
| 98 | if (this == POINT_INFINITY) return false; | ||
| 99 | if (obj instanceof ECPoint) { | ||
| 100 | return ((x.equals(((ECPoint)obj).x)) && | ||
| 101 | (y.equals(((ECPoint)obj).y))); | ||
| 102 | } | ||
| 103 | return false; | ||
| 104 | } | ||
| 105 | |||
| 106 | /** | ||
| 107 | * Returns a hash code value for this elliptic curve point. | ||
| 108 | * @return a hash code value. | ||
| 109 | */ | ||
| 110 | public int hashCode() { | ||
| 111 | if (this == POINT_INFINITY) return 0; | ||
| 112 | return x.hashCode() << 5 + y.hashCode(); | ||
| 113 | } | ||
| 114 | } | ||