/*
* 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.
*/
/**
* @author Elena Semukhina
*/
package org.apache.harmony.tests.java.math;
import junit.framework.TestCase;
import java.math.BigInteger;
/**
* Class: java.math.BigInteger
* Method: multiply
*/
public class BigIntegerMultiplyTest extends TestCase {
/**
* Multiply two negative numbers of the same length
*/
public void testCase1() {
byte aBytes[] = {1, 2, 3, 4, 5, 6, 7, 1, 2, 3};
byte bBytes[] = {10, 20, 30, 40, 50, 60, 70, 10, 20, 30};
int aSign = -1;
int bSign = -1;
byte rBytes[] = {10, 40, 100, -55, 96, 51, 76, 40, -45, 85, 105, 4, 28, -86, -117, -52, 100, 120, 90};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = new BigInteger(bSign, bBytes);
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", 1, result.signum());
}
/**
* Multiply two numbers of the same length and different signs.
* The first is negative.
*/
public void testCase2() {
byte aBytes[] = {1, 2, 3, 4, 5, 6, 7, 1, 2, 3};
byte bBytes[] = {10, 20, 30, 40, 50, 60, 70, 10, 20, 30};
int aSign = -1;
int bSign = 1;
byte rBytes[] = {-11, -41, -101, 54, -97, -52, -77, -41, 44, -86, -106, -5, -29, 85, 116, 51, -101, -121, -90};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = new BigInteger(bSign, bBytes);
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", -1, result.signum());
}
/**
* Multiply two positive numbers of different length.
* The first is longer.
*/
public void testCase3() {
byte aBytes[] = {1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 1, 2, 3, 4, 5};
byte bBytes[] = {10, 20, 30, 40, 50, 60, 70, 10, 20, 30};
int aSign = 1;
int bSign = 1;
byte rBytes[] = {10, 40, 100, -55, 96, 51, 76, 40, -45, 85, 115, 44, -127,
115, -21, -62, -15, 85, 64, -87, -2, -36, -36, -106};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = new BigInteger(bSign, bBytes);
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", 1, result.signum());
}
/**
* Multiply two positive numbers of different length.
* The second is longer.
*/
public void testCase4() {
byte aBytes[] = {10, 20, 30, 40, 50, 60, 70, 10, 20, 30};
byte bBytes[] = {1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 1, 2, 3, 4, 5};
int aSign = 1;
int bSign = 1;
byte rBytes[] = {10, 40, 100, -55, 96, 51, 76, 40, -45, 85, 115, 44, -127,
115, -21, -62, -15, 85, 64, -87, -2, -36, -36, -106};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = new BigInteger(bSign, bBytes);
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", 1, result.signum());
}
/**
* Multiply two numbers of different length and different signs.
* The first is positive.
* The first is longer.
*/
public void testCase5() {
byte aBytes[] = {1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 1, 2, 3, 4, 5};
byte bBytes[] = {10, 20, 30, 40, 50, 60, 70, 10, 20, 30};
int aSign = 1;
int bSign = -1;
byte rBytes[] = {-11, -41, -101, 54, -97, -52, -77, -41, 44, -86, -116, -45, 126,
-116, 20, 61, 14, -86, -65, 86, 1, 35, 35, 106};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = new BigInteger(bSign, bBytes);
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", -1, result.signum());
}
/**
* Multiply two numbers of different length and different signs.
* The first is positive.
* The second is longer.
*/
public void testCase6() {
byte aBytes[] = {10, 20, 30, 40, 50, 60, 70, 10, 20, 30};
byte bBytes[] = {1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 1, 2, 3, 4, 5};
int aSign = 1;
int bSign = -1;
byte rBytes[] = {-11, -41, -101, 54, -97, -52, -77, -41, 44, -86, -116, -45, 126,
-116, 20, 61, 14, -86, -65, 86, 1, 35, 35, 106};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = new BigInteger(bSign, bBytes);
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", -1, result.signum());
}
/**
* Multiply a number by zero.
*/
public void testCase7() {
byte aBytes[] = {1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 1, 2, 3, 4, 5};
byte bBytes[] = {0};
int aSign = 1;
int bSign = 0;
byte rBytes[] = {0};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = new BigInteger(bSign, bBytes);
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", 0, result.signum());
}
/**
* Multiply a number by ZERO.
*/
public void testCase8() {
byte aBytes[] = {1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 1, 2, 3, 4, 5};
int aSign = 1;
byte rBytes[] = {0};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = BigInteger.ZERO;
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", 0, result.signum());
}
/**
* Multiply a positive number by ONE.
*/
public void testCase9() {
byte aBytes[] = {1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 1, 2, 3, 4, 5};
int aSign = 1;
byte rBytes[] = {1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 1, 2, 3, 4, 5};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = BigInteger.ONE;
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", 1, result.signum());
}
/**
* Multiply a negative number by ONE.
*/
public void testCase10() {
byte aBytes[] = {1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 1, 2, 3, 4, 5};
int aSign = -1;
byte rBytes[] = {-2, -3, -4, -5, -6, -7, -8, -2, -3, -4, -2, -3, -4, -5, -5};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = BigInteger.ONE;
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", -1, result.signum());
}
/**
* Multiply two numbers of 4 bytes length.
*/
public void testIntbyInt1() {
byte aBytes[] = {10, 20, 30, 40};
byte bBytes[] = {1, 2, 3, 4};
int aSign = 1;
int bSign = -1;
byte rBytes[] = {-11, -41, -101, 55, 5, 15, 96};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = new BigInteger(bSign, bBytes);
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", -1, result.signum());
}
/**
* Multiply two numbers of 4 bytes length.
*/
public void testIntbyInt2() {
byte aBytes[] = {-1, -1, -1, -1};
byte bBytes[] = {-1, -1, -1, -1};
int aSign = 1;
int bSign = 1;
byte rBytes[] = {0, -1, -1, -1, -2, 0, 0, 0, 1};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger bNumber = new BigInteger(bSign, bBytes);
BigInteger result = aNumber.multiply(bNumber);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", 1, result.signum());
}
/**
* Negative exponent.
*/
public void testPowException() {
byte aBytes[] = {1, 2, 3, 4, 5, 6, 7};
int aSign = 1;
int exp = -5;
BigInteger aNumber = new BigInteger(aSign, aBytes);
try {
aNumber.pow(exp);
fail("ArithmeticException has not been caught");
} catch (ArithmeticException e) {
assertEquals("Improper exception message", "Negative exponent", e.getMessage());
}
}
/**
* Exponentiation of a negative number to an odd exponent.
*/
public void testPowNegativeNumToOddExp() {
byte aBytes[] = {50, -26, 90, 69, 120, 32, 63, -103, -14, 35};
int aSign = -1;
int exp = 5;
byte rBytes[] = {-21, -94, -42, -15, -127, 113, -50, -88, 115, -35, 3,
59, -92, 111, -75, 103, -42, 41, 34, -114, 99, -32, 105, -59, 127,
45, 108, 74, -93, 105, 33, 12, -5, -20, 17, -21, -119, -127, -115,
27, -122, 26, -67, 109, -125, 16, 91, -70, 109};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger result = aNumber.pow(exp);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", -1, result.signum());
}
/**
* Exponentiation of a negative number to an even exponent.
*/
public void testPowNegativeNumToEvenExp() {
byte aBytes[] = {50, -26, 90, 69, 120, 32, 63, -103, -14, 35};
int aSign = -1;
int exp = 4;
byte rBytes[] = {102, 107, -122, -43, -52, -20, -27, 25, -9, 88, -13,
75, 78, 81, -33, -77, 39, 27, -37, 106, 121, -73, 108, -47, -101,
80, -25, 71, 13, 94, -7, -33, 1, -17, -65, -70, -61, -3, -47};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger result = aNumber.pow(exp);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", 1, result.signum());
}
/**
* Exponentiation of a negative number to zero exponent.
*/
public void testPowNegativeNumToZeroExp() {
byte aBytes[] = {50, -26, 90, 69, 120, 32, 63, -103, -14, 35};
int aSign = -1;
int exp = 0;
byte rBytes[] = {1};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger result = aNumber.pow(exp);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", 1, result.signum());
}
/**
* Exponentiation of a positive number.
*/
public void testPowPositiveNum() {
byte aBytes[] = {50, -26, 90, 69, 120, 32, 63, -103, -14, 35};
int aSign = 1;
int exp = 5;
byte rBytes[] = {20, 93, 41, 14, 126, -114, 49, 87, -116, 34, -4, -60,
91, -112, 74, -104, 41, -42, -35, 113, -100, 31, -106, 58, -128,
-46, -109, -75, 92, -106, -34, -13, 4, 19, -18, 20, 118, 126, 114,
-28, 121, -27, 66, -110, 124, -17, -92, 69, -109};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger result = aNumber.pow(exp);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", 1, result.signum());
}
/**
* Exponentiation of a negative number to zero exponent.
*/
public void testPowPositiveNumToZeroExp() {
byte aBytes[] = {50, -26, 90, 69, 120, 32, 63, -103, -14, 35};
int aSign = 1;
int exp = 0;
byte rBytes[] = {1};
BigInteger aNumber = new BigInteger(aSign, aBytes);
BigInteger result = aNumber.pow(exp);
byte resBytes[] = new byte[rBytes.length];
resBytes = result.toByteArray();
for(int i = 0; i < resBytes.length; i++) {
assertTrue(resBytes[i] == rBytes[i]);
}
assertEquals("incorrect sign", 1, result.signum());
}
}