1 /*
   2  * Copyright 2001 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  */
  23 
  24 /*
  25  * @test
  26  * @bug 4428772
  27  * @summary Testing recognition of "NaN" and "Infinity" strings
  28  * @author Joseph D. Darcy
  29  */
  30 
  31 
  32 public class NaNInfinityParsing {
  33     /*
  34      * Regression tests for:
  35      * 4428772 -- Establish invariant for Float & Double classes and
  36      * their string representations
  37      *
  38      * Added capability for parse{Float, Double} and related methods
  39      * to recognize "NaN" and "Infinity" strings so that
  40      * parseDouble(toString(d)) will always return the original
  41      * floating-point value.
  42      */
  43 
  44     static String NaNStrings[] = {
  45         "NaN",
  46         "+NaN",
  47         "-NaN"
  48     };
  49 
  50     static String infinityStrings[] = {
  51         "Infinity",
  52         "+Infinity",
  53         "-Infinity",
  54     };
  55 
  56     static String invalidStrings[] = {
  57         "+",
  58         "-",
  59         "@",
  60         "N",
  61         "Na",
  62         "Nan",
  63         "NaNf",
  64         "NaNd",
  65         "NaNF",
  66         "NaND",
  67         "+N",
  68         "+Na",
  69         "+Nan",
  70         "+NaNf",
  71         "+NaNd",
  72         "+NaNF",
  73         "+NaND",
  74         "-N",
  75         "-Na",
  76         "-Nan",
  77         "-NaNf",
  78         "-NaNd",
  79         "-NaNF",
  80         "-NaND",
  81         "I",
  82         "In",
  83         "Inf",
  84         "Infi",
  85         "Infin",
  86         "Infini",
  87         "Infinit",
  88         "InfinitY",
  89         "Infinityf",
  90         "InfinityF",
  91         "Infinityd",
  92         "InfinityD",
  93         "+I",
  94         "+In",
  95         "+Inf",
  96         "+Infi",
  97         "+Infin",
  98         "+Infini",
  99         "+Infinit",
 100         "+InfinitY",
 101         "+Infinityf",
 102         "+InfinityF",
 103         "+Infinityd",
 104         "+InfinityD",
 105         "-I",
 106         "-In",
 107         "-Inf",
 108         "-Infi",
 109         "-Infin",
 110         "-Infini",
 111         "-Infinit",
 112         "-InfinitY",
 113         "-Infinityf",
 114         "-InfinityF",
 115         "-Infinityd",
 116         "-InfinityD",
 117         "NaNInfinity",
 118         "InfinityNaN",
 119         "nan",
 120         "infinity"
 121     };
 122 
 123     public static void main(String [] argv) throws Exception {
 124         int i;
 125         double d;
 126 
 127         // Test valid NaN strings
 128         for(i = 0; i < NaNStrings.length; i++) {
 129             if(!Double.isNaN(d=Double.parseDouble(NaNStrings[i]))) {
 130                 throw new RuntimeException("NaN string ``" + NaNStrings[i]
 131                                            + "'' did not parse as a NaN; returned " +
 132                                            d + " instead.");
 133             }
 134         }
 135 
 136         // Test valid Infinity strings
 137         for(i = 0; i < infinityStrings.length; i++) {
 138             if(!Double.isInfinite(d=Double.parseDouble(infinityStrings[i]))) {
 139                 throw new RuntimeException("Infinity string ``" +
 140                                            infinityStrings[i] +
 141                                            "'' did not parse as infinity; returned " +
 142                                            d + "instead.");
 143             }
 144             // check sign of result
 145 
 146             boolean negative = (infinityStrings[i].charAt(0) == '-');
 147             if(d != (negative?Double.NEGATIVE_INFINITY:
 148                           Double.POSITIVE_INFINITY))
 149                 throw new RuntimeException("Infinity has wrong sign;" +
 150                                            (negative?"positive instead of negative.":
 151                                             "negative instead of positive."));
 152         }
 153 
 154         // Test almost valid strings
 155         for(i = 0; i < invalidStrings.length; i++) {
 156             try {
 157                 double result;
 158                 d = Double.parseDouble(invalidStrings[i]);
 159                 throw new RuntimeException("Invalid string ``" +
 160                                            invalidStrings[i]
 161                                            +"'' parsed as " + d + ".");
 162             }
 163             catch(NumberFormatException e) {
 164                 // expected
 165             }
 166         }
 167 
 168     }
 169 }