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/*
* Copyright (c) 1998, 2013, 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.
*/
import static java.math.BigInteger.ONE;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Random;
/**
* @test
* @bug 7131192
* @summary This test ensures that BigInteger.floatValue() and
* BigInteger.doubleValue() behave correctly.
* @author Louis Wasserman
*/
public class PrimitiveConversionTests {
static final List<BigInteger> ALL_BIGINTEGER_CANDIDATES;
static {
List<BigInteger> samples = new ArrayList<>();
// Now add values near 2^N for lots of values of N.
for (int exponent : Arrays.asList(0, 1, 2, 3, 4, 5, 6, 7, 31, 32, 33,
34, 62, 63, 64, 65, 71, 72, 73, 79, 80, 81, 255, 256, 257, 511,
512, 513, Double.MAX_EXPONENT - 1, Double.MAX_EXPONENT,
Double.MAX_EXPONENT + 1, 2000, 2001, 2002)) {
BigInteger x = ONE.shiftLeft(exponent);
for (BigInteger y : Arrays.asList(x, x.add(ONE), x.subtract(ONE))) {
samples.add(y);
samples.add(y.negate());
}
}
Random rng = new Random(1234567);
for (int i = 0; i < 2000; i++) {
samples.add(new BigInteger(rng.nextInt(2000), rng));
}
ALL_BIGINTEGER_CANDIDATES = Collections.unmodifiableList(samples);
}
public static int testDoubleValue() {
int failures = 0;
for (BigInteger big : ALL_BIGINTEGER_CANDIDATES) {
double expected = Double.parseDouble(big.toString());
double actual = big.doubleValue();
// should be bitwise identical
if (Double.doubleToRawLongBits(expected) != Double
.doubleToRawLongBits(actual)) {
System.out.println(big);
failures++;
}
}
return failures;
}
public static int testFloatValue() {
int failures = 0;
for (BigInteger big : ALL_BIGINTEGER_CANDIDATES) {
float expected = Float.parseFloat(big.toString());
float actual = big.floatValue();
// should be bitwise identical
if (Float.floatToRawIntBits(expected) != Float
.floatToRawIntBits(actual)) {
System.out.println(big + " " + expected + " " + actual);
failures++;
}
}
return failures;
}
public static void main(String[] args) {
int failures = testDoubleValue();
failures += testFloatValue();
if (failures > 0) {
throw new RuntimeException("Incurred " + failures
+ " failures while testing primitive conversions.");
}
}
}
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