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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.
*/
/*
* @test
* @bug 4160406 4705734 4707389 6358355 7032154
* @summary Tests for Float.parseFloat method
*/
import java.math.BigDecimal;
import java.math.BigInteger;
public class ParseFloat {
private static final BigDecimal HALF = BigDecimal.valueOf(0.5);
private static void fail(String val, float n) {
throw new RuntimeException("Float.parseFloat failed. String:" +
val + " Result:" + n);
}
private static void check(String val) {
float n = Float.parseFloat(val);
boolean isNegativeN = n < 0 || n == 0 && 1/n < 0;
float na = Math.abs(n);
String s = val.trim().toLowerCase();
switch (s.charAt(s.length() - 1)) {
case 'd':
case 'f':
s = s.substring(0, s.length() - 1);
break;
}
boolean isNegative = false;
if (s.charAt(0) == '+') {
s = s.substring(1);
} else if (s.charAt(0) == '-') {
s = s.substring(1);
isNegative = true;
}
if (s.equals("nan")) {
if (!Float.isNaN(n)) {
fail(val, n);
}
return;
}
if (Float.isNaN(n)) {
fail(val, n);
}
if (isNegativeN != isNegative)
fail(val, n);
if (s.equals("infinity")) {
if (na != Float.POSITIVE_INFINITY) {
fail(val, n);
}
return;
}
BigDecimal bd;
if (s.startsWith("0x")) {
s = s.substring(2);
int indP = s.indexOf('p');
long exp = Long.parseLong(s.substring(indP + 1));
int indD = s.indexOf('.');
String significand;
if (indD >= 0) {
significand = s.substring(0, indD) + s.substring(indD + 1, indP);
exp -= 4*(indP - indD - 1);
} else {
significand = s.substring(0, indP);
}
bd = new BigDecimal(new BigInteger(significand, 16));
if (exp >= 0) {
bd = bd.multiply(BigDecimal.valueOf(2).pow((int)exp));
} else {
bd = bd.divide(BigDecimal.valueOf(2).pow((int)-exp));
}
} else {
bd = new BigDecimal(s);
}
BigDecimal l, u;
if (Float.isInfinite(na)) {
l = new BigDecimal(Float.MAX_VALUE).add(new BigDecimal(Math.ulp(Float.MAX_VALUE)).multiply(HALF));
u = null;
} else {
l = new BigDecimal(na).subtract(new BigDecimal(Math.ulp(-Math.nextUp(-na))).multiply(HALF));
u = new BigDecimal(na).add(new BigDecimal(Math.ulp(n)).multiply(HALF));
}
int cmpL = bd.compareTo(l);
int cmpU = u != null ? bd.compareTo(u) : -1;
if ((Float.floatToIntBits(n) & 1) != 0) {
if (cmpL <= 0 || cmpU >= 0) {
fail(val, n);
}
} else {
if (cmpL < 0 || cmpU > 0) {
fail(val, n);
}
}
}
private static void check(String val, float expected) {
float n = Float.parseFloat(val);
if (n != expected)
fail(val, n);
check(val);
}
private static void rudimentaryTest() {
check(new String(""+Float.MIN_VALUE), Float.MIN_VALUE);
check(new String(""+Float.MAX_VALUE), Float.MAX_VALUE);
check("10", (float) 10.0);
check("10.0", (float) 10.0);
check("10.01", (float) 10.01);
check("-10", (float) -10.0);
check("-10.00", (float) -10.0);
check("-10.01", (float) -10.01);
// bug 6358355
check("144115196665790480", 0x1.000002p57f);
check("144115196665790481", 0x1.000002p57f);
check("0.050000002607703203", 0.05f);
check("0.050000002607703204", 0.05f);
check("0.050000002607703205", 0.05f);
check("0.050000002607703206", 0.05f);
check("0.050000002607703207", 0.05f);
check("0.050000002607703208", 0.05f);
check("0.050000002607703209", 0.050000004f);
}
static String badStrings[] = {
"",
"+",
"-",
"+e",
"-e",
"+e170",
"-e170",
// Make sure intermediate white space is not deleted.
"1234 e10",
"-1234 e10",
// Control characters in the interior of a string are not legal
"1\u0007e1",
"1e\u00071",
// NaN and infinity can't have trailing type suffices or exponents
"NaNf",
"NaNF",
"NaNd",
"NaND",
"-NaNf",
"-NaNF",
"-NaNd",
"-NaND",
"+NaNf",
"+NaNF",
"+NaNd",
"+NaND",
"Infinityf",
"InfinityF",
"Infinityd",
"InfinityD",
"-Infinityf",
"-InfinityF",
"-Infinityd",
"-InfinityD",
"+Infinityf",
"+InfinityF",
"+Infinityd",
"+InfinityD",
"NaNe10",
"-NaNe10",
"+NaNe10",
"Infinitye10",
"-Infinitye10",
"+Infinitye10",
// Non-ASCII digits are not recognized
"\u0661e\u0661", // 1e1 in Arabic-Indic digits
"\u06F1e\u06F1", // 1e1 in Extended Arabic-Indic digits
"\u0967e\u0967" // 1e1 in Devanagari digits
};
static String goodStrings[] = {
"NaN",
"+NaN",
"-NaN",
"Infinity",
"+Infinity",
"-Infinity",
"1.1e-23f",
".1e-23f",
"1e-23",
"1f",
"1",
"2",
"1234",
"-1234",
"+1234",
"2147483647", // Integer.MAX_VALUE
"2147483648",
"-2147483648", // Integer.MIN_VALUE
"-2147483649",
"16777215",
"16777216", // 2^24
"16777217",
"-16777215",
"-16777216", // -2^24
"-16777217",
"9007199254740991",
"9007199254740992", // 2^53
"9007199254740993",
"-9007199254740991",
"-9007199254740992", // -2^53
"-9007199254740993",
"9223372036854775807",
"9223372036854775808", // Long.MAX_VALUE
"9223372036854775809",
"-9223372036854775808",
"-9223372036854775809", // Long.MIN_VALUE
"-9223372036854775810"
};
static String paddedBadStrings[];
static String paddedGoodStrings[];
static {
String pad = " \t\n\r\f\u0001\u000b\u001f";
paddedBadStrings = new String[badStrings.length];
for(int i = 0 ; i < badStrings.length; i++)
paddedBadStrings[i] = pad + badStrings[i] + pad;
paddedGoodStrings = new String[goodStrings.length];
for(int i = 0 ; i < goodStrings.length; i++)
paddedGoodStrings[i] = pad + goodStrings[i] + pad;
}
/*
* Throws an exception if <code>Input</code> is
* <code>exceptionalInput</code> and {@link Float.parseFloat
* parseFloat} does <em>not</em> throw an exception or if
* <code>Input</code> is not <code>exceptionalInput</code> and
* <code>parseFloat</code> throws an exception. This method does
* not attempt to test whether the string is converted to the
* proper value; just whether the input is accepted appropriately
* or not.
*/
private static void testParsing(String [] input,
boolean exceptionalInput) {
for(int i = 0; i < input.length; i++) {
double d;
try {
d = Float.parseFloat(input[i]);
check(input[i]);
}
catch (NumberFormatException e) {
if (! exceptionalInput) {
throw new RuntimeException("Float.parseFloat rejected " +
"good string `" + input[i] +
"'.");
}
break;
}
if (exceptionalInput) {
throw new RuntimeException("Float.parseFloat accepted " +
"bad string `" + input[i] +
"'.");
}
}
}
/**
* For each power of two, test at boundaries of
* region that should convert to that value.
*/
private static void testPowers() {
for(int i = -149; i <= +127; i++) {
float f = Math.scalb(1.0f, i);
BigDecimal f_BD = new BigDecimal(f);
BigDecimal lowerBound = f_BD.subtract(new BigDecimal(Math.ulp(-Math.nextUp(-f))).multiply(HALF));
BigDecimal upperBound = f_BD.add(new BigDecimal(Math.ulp(f)).multiply(HALF));
check(lowerBound.toString());
check(upperBound.toString());
}
check(new BigDecimal(Float.MAX_VALUE).add(new BigDecimal(Math.ulp(Float.MAX_VALUE)).multiply(HALF)).toString());
}
public static void main(String[] args) throws Exception {
rudimentaryTest();
testParsing(goodStrings, false);
testParsing(paddedGoodStrings, false);
testParsing(badStrings, true);
testParsing(paddedBadStrings, true);
testPowers();
}
}
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