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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

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 * 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.

 *

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 */

/*

 * @test

 * @bug 4826774 4926547

 * @summary Tests for {Float, Double}.toHexString methods

 * @library ../Math

 * @build DoubleConsts

 * @run main ToHexString

 * @author Joseph D. Darcy

 */

import java.util.regex.*;

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 == Double.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");

        }

    }

}