| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.hadoop.examples.pi.math; |
| |
| import java.math.BigInteger; |
| import java.util.Random; |
| |
| public class TestLongLong extends junit.framework.TestCase { |
| static final Random RAN = new Random(); |
| static final long MASK = (1L << (LongLong.SIZE >> 1)) - 1; |
| |
| static long nextPositiveLong() { |
| return RAN.nextLong() & MASK; |
| } |
| |
| static void verifyMultiplication(long a, long b) { |
| final LongLong ll = LongLong.multiplication(new LongLong(), a, b); |
| final BigInteger bi = BigInteger.valueOf(a).multiply(BigInteger.valueOf(b)); |
| |
| final String s = String.format("\na = %x\nb = %x\nll= " + ll + "\nbi= " + bi.toString(16) + "\n", a, b); |
| //System.out.println(s); |
| assertEquals(s, bi, ll.toBigInteger()); |
| } |
| |
| public void testMultiplication() { |
| for(int i = 0; i < 100; i++) { |
| final long a = nextPositiveLong(); |
| final long b = nextPositiveLong(); |
| verifyMultiplication(a, b); |
| } |
| final long max = Long.MAX_VALUE & MASK; |
| verifyMultiplication(max, max); |
| } |
| |
| static void verifyRightShift(long a, long b) { |
| final LongLong ll = new LongLong().set(a, b); |
| final BigInteger bi = ll.toBigInteger(); |
| |
| for(int i = 0; i < LongLong.SIZE >> 1; i++) { |
| final long result = ll.shiftRight(i) & MASK; |
| final long expected = bi.shiftRight(i).longValue() & MASK; |
| final String s = String.format("\na = %x\nb = %x\nll= " + ll + "\nbi= " + bi.toString(16) + "\n", a, b); |
| assertEquals(s, expected, result); |
| } |
| |
| final String s = String.format("\na = %x\nb = %x\nll= " + ll + "\nbi= " + bi.toString(16) + "\n", a, b); |
| //System.out.println(s); |
| assertEquals(s, bi, ll.toBigInteger()); |
| } |
| |
| public void testRightShift() { |
| for(int i = 0; i < 1000; i++) { |
| final long a = nextPositiveLong(); |
| final long b = nextPositiveLong(); |
| verifyMultiplication(a, b); |
| } |
| } |
| } |