/* * Copyright (c) 2003, 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 4826774 4926547 * @summary Tests for {Float, Double}.toHexString methods * @author Joseph D. Darcy */ import java.util.regex.*; import sun.misc.DoubleConsts; public class ToHexString { private ToHexString() {} /* * Given a double value, create a hexadecimal floating-point * string via an intermediate long hex string. */ static String doubleToHexString(double d) { return hexLongStringtoHexDoubleString(Long.toHexString(Double.doubleToLongBits(d))); } /* * Transform the hexadecimal long output into the equivalent * hexadecimal double value. */ static String hexLongStringtoHexDoubleString(String transString) { transString = transString.toLowerCase(); String zeros = ""; StringBuffer result = new StringBuffer(24); for(int i = 0; i < (16 - transString.length()); i++, zeros += "0"); transString = zeros + transString; // assert transString.length == 16; char topChar; // Extract sign if((topChar=transString.charAt(0)) >= '8' ) {// 8, 9, a, A, b, B, ... result.append("-"); // clear sign bit transString = Character.toString(Character.forDigit(Character.digit(topChar, 16) - 8, 16)) + transString.substring(1,16); } // check for NaN and infinity String signifString = transString.substring(3,16); if( transString.substring(0,3).equals("7ff") ) { if(signifString.equals("0000000000000")) { result.append("Infinity"); } else result.append("NaN"); } else { // finite value // Extract exponent int exponent = Integer.parseInt(transString.substring(0,3), 16) - DoubleConsts.EXP_BIAS; result.append("0x"); if (exponent == DoubleConsts.MIN_EXPONENT - 1) { // zero or subnormal if(signifString.equals("0000000000000")) { result.append("0.0p0"); } else { result.append("0." + signifString.replaceFirst("0+$", "").replaceFirst("^$", "0") + "p-1022"); } } else { // normal value result.append("1." + signifString.replaceFirst("0+$", "").replaceFirst("^$", "0") + "p" + exponent); } } return result.toString(); } public static int toHexStringTests() { int failures = 0; String [][] testCases1 = { {"Infinity", "Infinity"}, {"-Infinity", "-Infinity"}, {"NaN", "NaN"}, {"-NaN", "NaN"}, {"0.0", "0x0.0p0"}, {"-0.0", "-0x0.0p0"}, {"1.0", "0x1.0p0"}, {"-1.0", "-0x1.0p0"}, {"2.0", "0x1.0p1"}, {"3.0", "0x1.8p1"}, {"0.5", "0x1.0p-1"}, {"0.25", "0x1.0p-2"}, {"1.7976931348623157e+308", "0x1.fffffffffffffp1023"}, // MAX_VALUE {"2.2250738585072014E-308", "0x1.0p-1022"}, // MIN_NORMAL {"2.225073858507201E-308", "0x0.fffffffffffffp-1022"}, // MAX_SUBNORMAL {"4.9e-324", "0x0.0000000000001p-1022"} // MIN_VALUE }; // Compare decimal string -> double -> hex string to hex string for (int i = 0; i < testCases1.length; i++) { String result; if(! (result=Double.toHexString(Double.parseDouble(testCases1[i][0]))). equals(testCases1[i][1])) { failures ++; System.err.println("For floating-point string " + testCases1[i][0] + ", expected hex output " + testCases1[i][1] + ", got " + result +"."); } } // Except for float subnormals, the output for numerically // equal float and double values should be the same. // Therefore, we will explicitly test float subnormal values. String [][] floatTestCases = { {"Infinity", "Infinity"}, {"-Infinity", "-Infinity"}, {"NaN", "NaN"}, {"-NaN", "NaN"}, {"0.0", "0x0.0p0"}, {"-0.0", "-0x0.0p0"}, {"1.0", "0x1.0p0"}, {"-1.0", "-0x1.0p0"}, {"2.0", "0x1.0p1"}, {"3.0", "0x1.8p1"}, {"0.5", "0x1.0p-1"}, {"0.25", "0x1.0p-2"}, {"3.4028235e+38f", "0x1.fffffep127"}, // MAX_VALUE {"1.17549435E-38f", "0x1.0p-126"}, // MIN_NORMAL {"1.1754942E-38", "0x0.fffffep-126"}, // MAX_SUBNORMAL {"1.4e-45f", "0x0.000002p-126"} // MIN_VALUE }; // Compare decimal string -> double -> hex string to hex string for (int i = 0; i < floatTestCases.length; i++) { String result; if(! (result=Float.toHexString(Float.parseFloat(floatTestCases[i][0]))). equals(floatTestCases[i][1])) { failures++; System.err.println("For floating-point string " + floatTestCases[i][0] + ", expected hex output\n" + floatTestCases[i][1] + ", got\n" + result +"."); } } // Particular floating-point values and hex equivalents, mostly // taken from fdlibm source. String [][] testCases2 = { {"+0.0", "0000000000000000"}, {"-0.0", "8000000000000000"}, {"+4.9e-324", "0000000000000001"}, {"-4.9e-324", "8000000000000001"}, // fdlibm k_sin.c {"+5.00000000000000000000e-01", "3FE0000000000000"}, {"-1.66666666666666324348e-01", "BFC5555555555549"}, {"+8.33333333332248946124e-03", "3F8111111110F8A6"}, {"-1.98412698298579493134e-04", "BF2A01A019C161D5"}, {"+2.75573137070700676789e-06", "3EC71DE357B1FE7D"}, {"-2.50507602534068634195e-08", "BE5AE5E68A2B9CEB"}, {"+1.58969099521155010221e-10", "3DE5D93A5ACFD57C"}, // fdlibm k_cos.c {"+4.16666666666666019037e-02", "3FA555555555554C"}, {"-1.38888888888741095749e-03", "BF56C16C16C15177"}, {"+2.48015872894767294178e-05", "3EFA01A019CB1590"}, {"-2.75573143513906633035e-07", "BE927E4F809C52AD"}, {"+2.08757232129817482790e-09", "3E21EE9EBDB4B1C4"}, {"-1.13596475577881948265e-11", "BDA8FAE9BE8838D4"}, // fdlibm e_rempio.c {"1.67772160000000000000e+07", "4170000000000000"}, {"6.36619772367581382433e-01", "3FE45F306DC9C883"}, {"1.57079632673412561417e+00", "3FF921FB54400000"}, {"6.07710050650619224932e-11", "3DD0B4611A626331"}, {"6.07710050630396597660e-11", "3DD0B4611A600000"}, {"2.02226624879595063154e-21", "3BA3198A2E037073"}, {"2.02226624871116645580e-21", "3BA3198A2E000000"}, {"8.47842766036889956997e-32", "397B839A252049C1"}, // fdlibm s_cbrt.c {"+5.42857142857142815906e-01", "3FE15F15F15F15F1"}, {"-7.05306122448979611050e-01", "BFE691DE2532C834"}, {"+1.41428571428571436819e+00", "3FF6A0EA0EA0EA0F"}, {"+1.60714285714285720630e+00", "3FF9B6DB6DB6DB6E"}, {"+3.57142857142857150787e-01", "3FD6DB6DB6DB6DB7"}, }; // Compare decimal string -> double -> hex string to // long hex string -> double hex string for (int i = 0; i < testCases2.length; i++) { String result; String expected; if(! (result=Double.toHexString(Double.parseDouble(testCases2[i][0]))). equals( expected=hexLongStringtoHexDoubleString(testCases2[i][1]) )) { failures ++; System.err.println("For floating-point string " + testCases2[i][0] + ", expected hex output " + expected + ", got " + result +"."); } } // Test random double values; // compare double -> Double.toHexString with local doubleToHexString java.util.Random rand = new java.util.Random(0); for (int i = 0; i < 1000; i++) { String result; String expected; double d = rand.nextDouble(); if(! (expected=doubleToHexString(d)).equals(result=Double.toHexString(d)) ) { failures ++; System.err.println("For floating-point value " + d + ", expected hex output " + expected + ", got " + result +"."); } } return failures; } public static void main(String argv[]) { int failures = 0; failures = toHexStringTests(); if (failures != 0) { throw new RuntimeException("" + failures + " failures while testing Double.toHexString"); } } }