/* * Copyright 2009 Google Inc. * * Licensed 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. */ /* * 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. * * INCLUDES MODIFICATIONS BY GOOGLE. */ /** * author Elena Semukhina */ package com.google.gwt.emultest.java.math; import com.google.gwt.emultest.java.util.EmulTestBase; import java.math.BigInteger; /** * Class: java.math.BigInteger Methods: modPow, modInverse, and gcd. */ public class BigIntegerModPowTest extends EmulTestBase { /** * gcd: both numbers are zeros. */ public void testGcdBothZeros() { byte rBytes[] = {0}; BigInteger aNumber = new BigInteger("0"); BigInteger bNumber = BigInteger.valueOf(0L); BigInteger result = aNumber.gcd(bNumber); byte resBytes[] = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 0, result.signum()); } /** * gcd: the first number is longer. */ public void testGcdFirstLonger() { byte aBytes[] = { -15, 24, 123, 56, -11, -112, -34, -98, 8, 10, 12, 14, 25, 125, -15, 28, -127}; byte bBytes[] = {-12, 1, 0, 0, 0, 23, 44, 55, 66}; int aSign = 1; int bSign = 1; byte rBytes[] = {7}; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger bNumber = new BigInteger(bSign, bBytes); BigInteger result = aNumber.gcd(bNumber); byte resBytes[] = new byte[rBytes.length]; resBytes = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 1, result.signum()); } /** * gcd: the first number is zero. */ public void testGcdFirstZero() { byte aBytes[] = {0}; byte bBytes[] = {15, 24, 123, 57, -15, 24, 123, 57, -15, 24, 123, 57}; int aSign = 1; int bSign = 1; byte rBytes[] = {15, 24, 123, 57, -15, 24, 123, 57, -15, 24, 123, 57}; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger bNumber = new BigInteger(bSign, bBytes); BigInteger result = aNumber.gcd(bNumber); byte resBytes[] = new byte[rBytes.length]; resBytes = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 1, result.signum()); } /** * gcd: the first number is ZERO. */ public void testGcdFirstZERO() { byte bBytes[] = {15, 24, 123, 57, -15, 24, 123, 57, -15, 24, 123, 57}; int bSign = 1; byte rBytes[] = {15, 24, 123, 57, -15, 24, 123, 57, -15, 24, 123, 57}; BigInteger aNumber = BigInteger.ZERO; BigInteger bNumber = new BigInteger(bSign, bBytes); BigInteger result = aNumber.gcd(bNumber); byte resBytes[] = new byte[rBytes.length]; resBytes = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 1, result.signum()); } /** * gcd: the second number is longer. */ public void testGcdSecondLonger() { byte aBytes[] = {-12, 1, 0, 0, 0, 23, 44, 55, 66}; byte bBytes[] = { -15, 24, 123, 56, -11, -112, -34, -98, 8, 10, 12, 14, 25, 125, -15, 28, -127}; int aSign = 1; int bSign = 1; byte rBytes[] = {7}; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger bNumber = new BigInteger(bSign, bBytes); BigInteger result = aNumber.gcd(bNumber); byte resBytes[] = new byte[rBytes.length]; resBytes = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 1, result.signum()); } /** * gcd: the second number is zero. */ public void testGcdSecondZero() { byte aBytes[] = {15, 24, 123, 57, -15, 24, 123, 57, -15, 24, 123, 57}; byte bBytes[] = {0}; int aSign = 1; int bSign = 1; byte rBytes[] = {15, 24, 123, 57, -15, 24, 123, 57, -15, 24, 123, 57}; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger bNumber = new BigInteger(bSign, bBytes); BigInteger result = aNumber.gcd(bNumber); byte resBytes[] = new byte[rBytes.length]; resBytes = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 1, result.signum()); } /** * modInverse: non-positive modulus. */ public void testmodInverseException() { byte aBytes[] = {1, 2, 3, 4, 5, 6, 7}; byte mBytes[] = {1, 2, 3}; int aSign = 1; int mSign = -1; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger modulus = new BigInteger(mSign, mBytes); try { aNumber.modInverse(modulus); fail("ArithmeticException has not been caught"); } catch (ArithmeticException e) { assertEquals("Improper exception message", "BigInteger: modulus not positive", e.getMessage()); } } /** * modInverse: negative number. */ public void testmodInverseNeg1() { byte aBytes[] = { 15, 24, 123, 56, -11, -112, -34, -98, 8, 10, 12, 14, 25, 125, -15, 28, -127}; byte mBytes[] = {2, 122, 45, 36, 100}; int aSign = -1; int mSign = 1; byte rBytes[] = {0, -41, 4, -91, 27}; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger modulus = new BigInteger(mSign, mBytes); BigInteger result = aNumber.modInverse(modulus); byte resBytes[] = new byte[rBytes.length]; resBytes = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 1, result.signum()); } /** * modInverse: negative number (another case: x < 0). */ public void testmodInverseNeg2() { byte aBytes[] = {-15, 24, 123, 57, -15, 24, 123, 57, -15, 24, 123, 57}; byte mBytes[] = {122, 2, 4, 122, 2, 4}; byte rBytes[] = {85, 47, 127, 4, -128, 45}; BigInteger aNumber = new BigInteger(aBytes); BigInteger modulus = new BigInteger(mBytes); BigInteger result = aNumber.modInverse(modulus); byte resBytes[] = new byte[rBytes.length]; resBytes = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 1, result.signum()); } /** * modInverse: non-invertible number. */ public void testmodInverseNonInvertible() { byte aBytes[] = { -15, 24, 123, 56, -11, -112, -34, -98, 8, 10, 12, 14, 25, 125, -15, 28, -127}; byte mBytes[] = {-12, 1, 0, 0, 0, 23, 44, 55, 66}; int aSign = 1; int mSign = 1; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger modulus = new BigInteger(mSign, mBytes); try { aNumber.modInverse(modulus); fail("ArithmeticException has not been caught"); } catch (ArithmeticException e) { assertEquals("Improper exception message", "BigInteger not invertible.", e.getMessage()); } } /** * modInverse: positive number. */ public void testmodInversePos1() { byte aBytes[] = { 24, 123, 56, -11, -112, -34, -98, 8, 10, 12, 14, 25, 125, -15, 28, -127}; byte mBytes[] = {122, 45, 36, 100, 122, 45}; int aSign = 1; int mSign = 1; byte rBytes[] = {47, 3, 96, 62, 87, 19}; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger modulus = new BigInteger(mSign, mBytes); BigInteger result = aNumber.modInverse(modulus); byte resBytes[] = new byte[rBytes.length]; resBytes = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 1, result.signum()); } /** * modInverse: positive number (another case: a < 0). */ public void testmodInversePos2() { byte aBytes[] = { 15, 24, 123, 56, -11, -112, -34, -98, 8, 10, 12, 14, 25, 125, -15, 28, -127}; byte mBytes[] = {2, 122, 45, 36, 100}; int aSign = 1; int mSign = 1; byte rBytes[] = {1, -93, 40, 127, 73}; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger modulus = new BigInteger(mSign, mBytes); BigInteger result = aNumber.modInverse(modulus); byte resBytes[] = new byte[rBytes.length]; resBytes = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 1, result.signum()); } /** * modPow: non-positive modulus. */ public void testModPowException() { byte aBytes[] = {1, 2, 3, 4, 5, 6, 7}; byte eBytes[] = {1, 2, 3, 4, 5}; byte mBytes[] = {1, 2, 3}; int aSign = 1; int eSign = 1; int mSign = -1; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger exp = new BigInteger(eSign, eBytes); BigInteger modulus = new BigInteger(mSign, mBytes); try { aNumber.modPow(exp, modulus); fail("ArithmeticException has not been caught"); } catch (ArithmeticException e) { assertEquals("Improper exception message", "BigInteger: modulus not positive", e.getMessage()); } } /** * modPow: negative exponent. */ public void testModPowNegExp() { byte aBytes[] = {-127, 100, 56, 7, 98, -1, 39, -128, 127, 75, 48, -7}; byte eBytes[] = {27, -15, 65, 39}; byte mBytes[] = {-128, 2, 3, 4, 5}; int aSign = 1; int eSign = -1; int mSign = 1; byte rBytes[] = {12, 118, 46, 86, 92}; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger exp = new BigInteger(eSign, eBytes); BigInteger modulus = new BigInteger(mSign, mBytes); BigInteger result = aNumber.modPow(exp, modulus); byte resBytes[] = new byte[rBytes.length]; resBytes = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 1, result.signum()); } /** * modPow: positive exponent. */ public void testModPowPosExp() { byte aBytes[] = {-127, 100, 56, 7, 98, -1, 39, -128, 127, 75, 48, -7}; byte eBytes[] = {27, -15, 65, 39}; byte mBytes[] = {-128, 2, 3, 4, 5}; int aSign = 1; int eSign = 1; int mSign = 1; byte rBytes[] = {113, 100, -84, -28, -85}; BigInteger aNumber = new BigInteger(aSign, aBytes); BigInteger exp = new BigInteger(eSign, eBytes); BigInteger modulus = new BigInteger(mSign, mBytes); BigInteger result = aNumber.modPow(exp, modulus); byte resBytes[] = new byte[rBytes.length]; resBytes = result.toByteArray(); for (int i = 0; i < resBytes.length; i++) { assertEquals("Byte " + i, rBytes[i], resBytes[i]); } assertEquals("incorrect sign", 1, result.signum()); } }