1 /* 2 * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /* 25 * @test 26 * @bug 4826774 4926547 27 * @summary Tests for {Float, Double}.toHexString methods 28 * @library /lib/testlibrary 29 * @build jdk.testlibrary.DoubleUtils 30 * @run main ToHexString 31 * @author Joseph D. Darcy 32 */ 33 34 import java.util.regex.*; 35 import static jdk.testlibrary.DoubleUtils.*; 36 37 public class ToHexString { 38 private ToHexString() {} 39 40 /* 41 * Given a double value, create a hexadecimal floating-point 42 * string via an intermediate long hex string. 43 */ 44 static String doubleToHexString(double d) { 45 return hexLongStringtoHexDoubleString(Long.toHexString(Double.doubleToLongBits(d))); 46 } 47 48 /* 49 * Transform the hexadecimal long output into the equivalent 50 * hexadecimal double value. 51 */ 52 static String hexLongStringtoHexDoubleString(String transString) { 53 transString = transString.toLowerCase(); 54 55 String zeros = ""; 56 StringBuffer result = new StringBuffer(24); 57 58 for(int i = 0; i < (16 - transString.length()); i++, zeros += "0"); 59 transString = zeros + transString; 60 61 // assert transString.length == 16; 62 63 char topChar; 64 // Extract sign 65 if((topChar=transString.charAt(0)) >= '8' ) {// 8, 9, a, A, b, B, ... 66 result.append("-"); 67 // clear sign bit 68 transString = 69 Character.toString(Character.forDigit(Character.digit(topChar, 16) - 8, 16)) + 70 transString.substring(1,16); 71 } 72 73 // check for NaN and infinity 74 String signifString = transString.substring(3,16); 75 76 if( transString.substring(0,3).equals("7ff") ) { 77 if(signifString.equals("0000000000000")) { 78 result.append("Infinity"); 79 } 80 else 81 result.append("NaN"); 82 } 83 else { // finite value 84 // Extract exponent 85 int exponent = Integer.parseInt(transString.substring(0,3), 16) - 86 EXP_BIAS; 87 result.append("0x"); 88 89 if (exponent == Double.MIN_EXPONENT - 1) { // zero or subnormal 90 if(signifString.equals("0000000000000")) { 91 result.append("0.0p0"); 92 } 93 else { 94 result.append("0." + signifString.replaceFirst("0+$", "").replaceFirst("^$", "0") + 95 "p-1022"); 96 } 97 } 98 else { // normal value 99 result.append("1." + signifString.replaceFirst("0+$", "").replaceFirst("^$", "0") + 100 "p" + exponent); 101 } 102 } 103 return result.toString(); 104 } 105 106 public static int toHexStringTests() { 107 int failures = 0; 108 String [][] testCases1 = { 109 {"Infinity", "Infinity"}, 110 {"-Infinity", "-Infinity"}, 111 {"NaN", "NaN"}, 112 {"-NaN", "NaN"}, 113 {"0.0", "0x0.0p0"}, 114 {"-0.0", "-0x0.0p0"}, 115 {"1.0", "0x1.0p0"}, 116 {"-1.0", "-0x1.0p0"}, 117 {"2.0", "0x1.0p1"}, 118 {"3.0", "0x1.8p1"}, 119 {"0.5", "0x1.0p-1"}, 120 {"0.25", "0x1.0p-2"}, 121 {"1.7976931348623157e+308", "0x1.fffffffffffffp1023"}, // MAX_VALUE 122 {"2.2250738585072014E-308", "0x1.0p-1022"}, // MIN_NORMAL 123 {"2.225073858507201E-308", "0x0.fffffffffffffp-1022"}, // MAX_SUBNORMAL 124 {"4.9e-324", "0x0.0000000000001p-1022"} // MIN_VALUE 125 }; 126 127 // Compare decimal string -> double -> hex string to hex string 128 for (int i = 0; i < testCases1.length; i++) { 129 String result; 130 if(! (result=Double.toHexString(Double.parseDouble(testCases1[i][0]))). 131 equals(testCases1[i][1])) { 132 failures ++; 133 System.err.println("For floating-point string " + testCases1[i][0] + 134 ", expected hex output " + testCases1[i][1] + ", got " + result +"."); 135 } 136 } 137 138 139 // Except for float subnormals, the output for numerically 140 // equal float and double values should be the same. 141 // Therefore, we will explicitly test float subnormal values. 142 String [][] floatTestCases = { 143 {"Infinity", "Infinity"}, 144 {"-Infinity", "-Infinity"}, 145 {"NaN", "NaN"}, 146 {"-NaN", "NaN"}, 147 {"0.0", "0x0.0p0"}, 148 {"-0.0", "-0x0.0p0"}, 149 {"1.0", "0x1.0p0"}, 150 {"-1.0", "-0x1.0p0"}, 151 {"2.0", "0x1.0p1"}, 152 {"3.0", "0x1.8p1"}, 153 {"0.5", "0x1.0p-1"}, 154 {"0.25", "0x1.0p-2"}, 155 {"3.4028235e+38f", "0x1.fffffep127"}, // MAX_VALUE 156 {"1.17549435E-38f", "0x1.0p-126"}, // MIN_NORMAL 157 {"1.1754942E-38", "0x0.fffffep-126"}, // MAX_SUBNORMAL 158 {"1.4e-45f", "0x0.000002p-126"} // MIN_VALUE 159 }; 160 // Compare decimal string -> double -> hex string to hex string 161 for (int i = 0; i < floatTestCases.length; i++) { 162 String result; 163 if(! (result=Float.toHexString(Float.parseFloat(floatTestCases[i][0]))). 164 equals(floatTestCases[i][1])) { 165 failures++; 166 System.err.println("For floating-point string " + floatTestCases[i][0] + 167 ", expected hex output\n" + floatTestCases[i][1] + ", got\n" + result +"."); 168 } 169 } 170 171 // Particular floating-point values and hex equivalents, mostly 172 // taken from fdlibm source. 173 String [][] testCases2 = { 174 {"+0.0", "0000000000000000"}, 175 {"-0.0", "8000000000000000"}, 176 {"+4.9e-324", "0000000000000001"}, 177 {"-4.9e-324", "8000000000000001"}, 178 179 // fdlibm k_sin.c 180 {"+5.00000000000000000000e-01", "3FE0000000000000"}, 181 {"-1.66666666666666324348e-01", "BFC5555555555549"}, 182 {"+8.33333333332248946124e-03", "3F8111111110F8A6"}, 183 {"-1.98412698298579493134e-04", "BF2A01A019C161D5"}, 184 {"+2.75573137070700676789e-06", "3EC71DE357B1FE7D"}, 185 {"-2.50507602534068634195e-08", "BE5AE5E68A2B9CEB"}, 186 {"+1.58969099521155010221e-10", "3DE5D93A5ACFD57C"}, 187 188 // fdlibm k_cos.c 189 {"+4.16666666666666019037e-02", "3FA555555555554C"}, 190 {"-1.38888888888741095749e-03", "BF56C16C16C15177"}, 191 {"+2.48015872894767294178e-05", "3EFA01A019CB1590"}, 192 {"-2.75573143513906633035e-07", "BE927E4F809C52AD"}, 193 {"+2.08757232129817482790e-09", "3E21EE9EBDB4B1C4"}, 194 {"-1.13596475577881948265e-11", "BDA8FAE9BE8838D4"}, 195 196 // fdlibm e_rempio.c 197 {"1.67772160000000000000e+07", "4170000000000000"}, 198 {"6.36619772367581382433e-01", "3FE45F306DC9C883"}, 199 {"1.57079632673412561417e+00", "3FF921FB54400000"}, 200 {"6.07710050650619224932e-11", "3DD0B4611A626331"}, 201 {"6.07710050630396597660e-11", "3DD0B4611A600000"}, 202 {"2.02226624879595063154e-21", "3BA3198A2E037073"}, 203 {"2.02226624871116645580e-21", "3BA3198A2E000000"}, 204 {"8.47842766036889956997e-32", "397B839A252049C1"}, 205 206 207 // fdlibm s_cbrt.c 208 {"+5.42857142857142815906e-01", "3FE15F15F15F15F1"}, 209 {"-7.05306122448979611050e-01", "BFE691DE2532C834"}, 210 {"+1.41428571428571436819e+00", "3FF6A0EA0EA0EA0F"}, 211 {"+1.60714285714285720630e+00", "3FF9B6DB6DB6DB6E"}, 212 {"+3.57142857142857150787e-01", "3FD6DB6DB6DB6DB7"}, 213 }; 214 215 // Compare decimal string -> double -> hex string to 216 // long hex string -> double hex string 217 for (int i = 0; i < testCases2.length; i++) { 218 String result; 219 String expected; 220 if(! (result=Double.toHexString(Double.parseDouble(testCases2[i][0]))). 221 equals( expected=hexLongStringtoHexDoubleString(testCases2[i][1]) )) { 222 failures ++; 223 System.err.println("For floating-point string " + testCases2[i][0] + 224 ", expected hex output " + expected + ", got " + result +"."); 225 } 226 } 227 228 // Test random double values; 229 // compare double -> Double.toHexString with local doubleToHexString 230 java.util.Random rand = new java.util.Random(0); 231 for (int i = 0; i < 1000; i++) { 232 String result; 233 String expected; 234 double d = rand.nextDouble(); 235 if(! (expected=doubleToHexString(d)).equals(result=Double.toHexString(d)) ) { 236 failures ++; 237 System.err.println("For floating-point value " + d + 238 ", expected hex output " + expected + ", got " + result +"."); 239 } 240 } 241 242 return failures; 243 } 244 245 public static void main(String argv[]) { 246 int failures = 0; 247 248 failures = toHexStringTests(); 249 250 if (failures != 0) { 251 throw new RuntimeException("" + failures + " failures while testing Double.toHexString"); 252 } 253 } 254 }