/* * Copyright (c) 2016, 2017, 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. * * 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 test.java.lang.Math; import java.math.BigInteger; import org.testng.annotations.Test; import static org.testng.Assert.assertEquals; // Android-removed: Private constructor, main() method, randomness tests. public class MultiplicationTests { // Calculate high 64 bits of 128 product using BigInteger. private static long multiplyHighBigInt(long x, long y) { return BigInteger.valueOf(x).multiply(BigInteger.valueOf(y)) .shiftRight(64).longValue(); } @Test public void testMultiplyHigh() { // check some boundary cases long[][] v = new long[][]{ {0L, 0L}, {-1L, 0L}, {0L, -1L}, {1L, 0L}, {0L, 1L}, {-1L, -1L}, {-1L, 1L}, {1L, -1L}, {1L, 1L}, {Long.MAX_VALUE, Long.MAX_VALUE}, {Long.MAX_VALUE, -Long.MAX_VALUE}, {-Long.MAX_VALUE, Long.MAX_VALUE}, {-Long.MAX_VALUE, -Long.MAX_VALUE}, {Long.MAX_VALUE, Long.MIN_VALUE}, {Long.MIN_VALUE, Long.MAX_VALUE}, {Long.MIN_VALUE, Long.MIN_VALUE} }; for (long[] xy : v) { long x = xy[0]; long y = xy[1]; long p1 = multiplyHighBigInt(x, y); long p2 = Math.multiplyHigh(x, y); assertEquals(p1, p2); } } }