emul/mini/src/main/java/java/lang/Math.java
author Jaroslav Tulach <jaroslav.tulach@apidesign.org>
Wed, 23 Jan 2013 20:39:23 +0100
branchemul
changeset 554 05224402145d
parent 551 emul/src/main/java/java/lang/Math.java@ca781bc82662
child 600 4ff4e27465e0
permissions -rw-r--r--
First attempt to separate 'mini' profile from the rest of JDK APIs
     1 /*
     2  * Copyright (c) 1994, 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.  Oracle designates this
     8  * particular file as subject to the "Classpath" exception as provided
     9  * by Oracle in the LICENSE file that accompanied this code.
    10  *
    11  * This code is distributed in the hope that it will be useful, but WITHOUT
    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    14  * version 2 for more details (a copy is included in the LICENSE file that
    15  * accompanied this code).
    16  *
    17  * You should have received a copy of the GNU General Public License version
    18  * 2 along with this work; if not, write to the Free Software Foundation,
    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    20  *
    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    22  * or visit www.oracle.com if you need additional information or have any
    23  * questions.
    24  */
    25 
    26 package java.lang;
    27 
    28 import org.apidesign.bck2brwsr.core.JavaScriptBody;
    29 
    30 
    31 /**
    32  * The class {@code Math} contains methods for performing basic
    33  * numeric operations such as the elementary exponential, logarithm,
    34  * square root, and trigonometric functions.
    35  *
    36  * <p>Unlike some of the numeric methods of class
    37  * {@code StrictMath}, all implementations of the equivalent
    38  * functions of class {@code Math} are not defined to return the
    39  * bit-for-bit same results.  This relaxation permits
    40  * better-performing implementations where strict reproducibility is
    41  * not required.
    42  *
    43  * <p>By default many of the {@code Math} methods simply call
    44  * the equivalent method in {@code StrictMath} for their
    45  * implementation.  Code generators are encouraged to use
    46  * platform-specific native libraries or microprocessor instructions,
    47  * where available, to provide higher-performance implementations of
    48  * {@code Math} methods.  Such higher-performance
    49  * implementations still must conform to the specification for
    50  * {@code Math}.
    51  *
    52  * <p>The quality of implementation specifications concern two
    53  * properties, accuracy of the returned result and monotonicity of the
    54  * method.  Accuracy of the floating-point {@code Math} methods
    55  * is measured in terms of <i>ulps</i>, units in the last place.  For
    56  * a given floating-point format, an ulp of a specific real number
    57  * value is the distance between the two floating-point values
    58  * bracketing that numerical value.  When discussing the accuracy of a
    59  * method as a whole rather than at a specific argument, the number of
    60  * ulps cited is for the worst-case error at any argument.  If a
    61  * method always has an error less than 0.5 ulps, the method always
    62  * returns the floating-point number nearest the exact result; such a
    63  * method is <i>correctly rounded</i>.  A correctly rounded method is
    64  * generally the best a floating-point approximation can be; however,
    65  * it is impractical for many floating-point methods to be correctly
    66  * rounded.  Instead, for the {@code Math} class, a larger error
    67  * bound of 1 or 2 ulps is allowed for certain methods.  Informally,
    68  * with a 1 ulp error bound, when the exact result is a representable
    69  * number, the exact result should be returned as the computed result;
    70  * otherwise, either of the two floating-point values which bracket
    71  * the exact result may be returned.  For exact results large in
    72  * magnitude, one of the endpoints of the bracket may be infinite.
    73  * Besides accuracy at individual arguments, maintaining proper
    74  * relations between the method at different arguments is also
    75  * important.  Therefore, most methods with more than 0.5 ulp errors
    76  * are required to be <i>semi-monotonic</i>: whenever the mathematical
    77  * function is non-decreasing, so is the floating-point approximation,
    78  * likewise, whenever the mathematical function is non-increasing, so
    79  * is the floating-point approximation.  Not all approximations that
    80  * have 1 ulp accuracy will automatically meet the monotonicity
    81  * requirements.
    82  *
    83  * @author  unascribed
    84  * @author  Joseph D. Darcy
    85  * @since   JDK1.0
    86  */
    87 
    88 public final class Math {
    89 
    90     /**
    91      * Don't let anyone instantiate this class.
    92      */
    93     private Math() {}
    94 
    95     /**
    96      * The {@code double} value that is closer than any other to
    97      * <i>e</i>, the base of the natural logarithms.
    98      */
    99     public static final double E = 2.7182818284590452354;
   100 
   101     /**
   102      * The {@code double} value that is closer than any other to
   103      * <i>pi</i>, the ratio of the circumference of a circle to its
   104      * diameter.
   105      */
   106     public static final double PI = 3.14159265358979323846;
   107 
   108     /**
   109      * Returns the trigonometric sine of an angle.  Special cases:
   110      * <ul><li>If the argument is NaN or an infinity, then the
   111      * result is NaN.
   112      * <li>If the argument is zero, then the result is a zero with the
   113      * same sign as the argument.</ul>
   114      *
   115      * <p>The computed result must be within 1 ulp of the exact result.
   116      * Results must be semi-monotonic.
   117      *
   118      * @param   a   an angle, in radians.
   119      * @return  the sine of the argument.
   120      */
   121     @JavaScriptBody(args="a", body="return Math.sin(a);")
   122     public static double sin(double a) {
   123         throw new UnsupportedOperationException();
   124     }
   125 
   126     /**
   127      * Returns the trigonometric cosine of an angle. Special cases:
   128      * <ul><li>If the argument is NaN or an infinity, then the
   129      * result is NaN.</ul>
   130      *
   131      * <p>The computed result must be within 1 ulp of the exact result.
   132      * Results must be semi-monotonic.
   133      *
   134      * @param   a   an angle, in radians.
   135      * @return  the cosine of the argument.
   136      */
   137     @JavaScriptBody(args="a", body="return Math.cos(a);")
   138     public static double cos(double a) {
   139         throw new UnsupportedOperationException();
   140     }
   141 
   142     /**
   143      * Returns the trigonometric tangent of an angle.  Special cases:
   144      * <ul><li>If the argument is NaN or an infinity, then the result
   145      * is NaN.
   146      * <li>If the argument is zero, then the result is a zero with the
   147      * same sign as the argument.</ul>
   148      *
   149      * <p>The computed result must be within 1 ulp of the exact result.
   150      * Results must be semi-monotonic.
   151      *
   152      * @param   a   an angle, in radians.
   153      * @return  the tangent of the argument.
   154      */
   155     @JavaScriptBody(args="a", body="return Math.tan(a);")
   156     public static double tan(double a) {
   157         throw new UnsupportedOperationException();
   158     }
   159 
   160     /**
   161      * Returns the arc sine of a value; the returned angle is in the
   162      * range -<i>pi</i>/2 through <i>pi</i>/2.  Special cases:
   163      * <ul><li>If the argument is NaN or its absolute value is greater
   164      * than 1, then the result is NaN.
   165      * <li>If the argument is zero, then the result is a zero with the
   166      * same sign as the argument.</ul>
   167      *
   168      * <p>The computed result must be within 1 ulp of the exact result.
   169      * Results must be semi-monotonic.
   170      *
   171      * @param   a   the value whose arc sine is to be returned.
   172      * @return  the arc sine of the argument.
   173      */
   174     @JavaScriptBody(args="a", body="return Math.asin(a);")
   175     public static double asin(double a) {
   176         throw new UnsupportedOperationException();
   177     }
   178 
   179     /**
   180      * Returns the arc cosine of a value; the returned angle is in the
   181      * range 0.0 through <i>pi</i>.  Special case:
   182      * <ul><li>If the argument is NaN or its absolute value is greater
   183      * than 1, then the result is NaN.</ul>
   184      *
   185      * <p>The computed result must be within 1 ulp of the exact result.
   186      * Results must be semi-monotonic.
   187      *
   188      * @param   a   the value whose arc cosine is to be returned.
   189      * @return  the arc cosine of the argument.
   190      */
   191     @JavaScriptBody(args="a", body="return Math.acos(a);")
   192     public static double acos(double a) {
   193         throw new UnsupportedOperationException();
   194     }
   195 
   196     /**
   197      * Returns the arc tangent of a value; the returned angle is in the
   198      * range -<i>pi</i>/2 through <i>pi</i>/2.  Special cases:
   199      * <ul><li>If the argument is NaN, then the result is NaN.
   200      * <li>If the argument is zero, then the result is a zero with the
   201      * same sign as the argument.</ul>
   202      *
   203      * <p>The computed result must be within 1 ulp of the exact result.
   204      * Results must be semi-monotonic.
   205      *
   206      * @param   a   the value whose arc tangent is to be returned.
   207      * @return  the arc tangent of the argument.
   208      */
   209     @JavaScriptBody(args="a", body="return Math.atan(a);")
   210     public static double atan(double a) {
   211         throw new UnsupportedOperationException();
   212     }
   213 
   214     /**
   215      * Converts an angle measured in degrees to an approximately
   216      * equivalent angle measured in radians.  The conversion from
   217      * degrees to radians is generally inexact.
   218      *
   219      * @param   angdeg   an angle, in degrees
   220      * @return  the measurement of the angle {@code angdeg}
   221      *          in radians.
   222      * @since   1.2
   223      */
   224     public static double toRadians(double angdeg) {
   225         return angdeg / 180.0 * PI;
   226     }
   227 
   228     /**
   229      * Converts an angle measured in radians to an approximately
   230      * equivalent angle measured in degrees.  The conversion from
   231      * radians to degrees is generally inexact; users should
   232      * <i>not</i> expect {@code cos(toRadians(90.0))} to exactly
   233      * equal {@code 0.0}.
   234      *
   235      * @param   angrad   an angle, in radians
   236      * @return  the measurement of the angle {@code angrad}
   237      *          in degrees.
   238      * @since   1.2
   239      */
   240     public static double toDegrees(double angrad) {
   241         return angrad * 180.0 / PI;
   242     }
   243 
   244     /**
   245      * Returns Euler's number <i>e</i> raised to the power of a
   246      * {@code double} value.  Special cases:
   247      * <ul><li>If the argument is NaN, the result is NaN.
   248      * <li>If the argument is positive infinity, then the result is
   249      * positive infinity.
   250      * <li>If the argument is negative infinity, then the result is
   251      * positive zero.</ul>
   252      *
   253      * <p>The computed result must be within 1 ulp of the exact result.
   254      * Results must be semi-monotonic.
   255      *
   256      * @param   a   the exponent to raise <i>e</i> to.
   257      * @return  the value <i>e</i><sup>{@code a}</sup>,
   258      *          where <i>e</i> is the base of the natural logarithms.
   259      */
   260     @JavaScriptBody(args="a", body="return Math.exp(a);")
   261     public static double exp(double a) {
   262         throw new UnsupportedOperationException();
   263     }
   264 
   265     /**
   266      * Returns the natural logarithm (base <i>e</i>) of a {@code double}
   267      * value.  Special cases:
   268      * <ul><li>If the argument is NaN or less than zero, then the result
   269      * is NaN.
   270      * <li>If the argument is positive infinity, then the result is
   271      * positive infinity.
   272      * <li>If the argument is positive zero or negative zero, then the
   273      * result is negative infinity.</ul>
   274      *
   275      * <p>The computed result must be within 1 ulp of the exact result.
   276      * Results must be semi-monotonic.
   277      *
   278      * @param   a   a value
   279      * @return  the value ln&nbsp;{@code a}, the natural logarithm of
   280      *          {@code a}.
   281      */
   282     @JavaScriptBody(args="a", body="return Math.log(a);")
   283     public static double log(double a) {
   284         throw new UnsupportedOperationException();
   285     }
   286 
   287     /**
   288      * Returns the base 10 logarithm of a {@code double} value.
   289      * Special cases:
   290      *
   291      * <ul><li>If the argument is NaN or less than zero, then the result
   292      * is NaN.
   293      * <li>If the argument is positive infinity, then the result is
   294      * positive infinity.
   295      * <li>If the argument is positive zero or negative zero, then the
   296      * result is negative infinity.
   297      * <li> If the argument is equal to 10<sup><i>n</i></sup> for
   298      * integer <i>n</i>, then the result is <i>n</i>.
   299      * </ul>
   300      *
   301      * <p>The computed result must be within 1 ulp of the exact result.
   302      * Results must be semi-monotonic.
   303      *
   304      * @param   a   a value
   305      * @return  the base 10 logarithm of  {@code a}.
   306      * @since 1.5
   307      */
   308     @JavaScriptBody(args="a", body="return Math.log(a) / Math.LN10;")
   309     public static double log10(double a) {
   310         throw new UnsupportedOperationException();
   311     }
   312 
   313     /**
   314      * Returns the correctly rounded positive square root of a
   315      * {@code double} value.
   316      * Special cases:
   317      * <ul><li>If the argument is NaN or less than zero, then the result
   318      * is NaN.
   319      * <li>If the argument is positive infinity, then the result is positive
   320      * infinity.
   321      * <li>If the argument is positive zero or negative zero, then the
   322      * result is the same as the argument.</ul>
   323      * Otherwise, the result is the {@code double} value closest to
   324      * the true mathematical square root of the argument value.
   325      *
   326      * @param   a   a value.
   327      * @return  the positive square root of {@code a}.
   328      *          If the argument is NaN or less than zero, the result is NaN.
   329      */
   330     @JavaScriptBody(args="a", body="return Math.sqrt(a);")
   331     public static double sqrt(double a) {
   332         throw new UnsupportedOperationException();
   333     }
   334 
   335     /**
   336      * Returns the smallest (closest to negative infinity)
   337      * {@code double} value that is greater than or equal to the
   338      * argument and is equal to a mathematical integer. Special cases:
   339      * <ul><li>If the argument value is already equal to a
   340      * mathematical integer, then the result is the same as the
   341      * argument.  <li>If the argument is NaN or an infinity or
   342      * positive zero or negative zero, then the result is the same as
   343      * the argument.  <li>If the argument value is less than zero but
   344      * greater than -1.0, then the result is negative zero.</ul> Note
   345      * that the value of {@code Math.ceil(x)} is exactly the
   346      * value of {@code -Math.floor(-x)}.
   347      *
   348      *
   349      * @param   a   a value.
   350      * @return  the smallest (closest to negative infinity)
   351      *          floating-point value that is greater than or equal to
   352      *          the argument and is equal to a mathematical integer.
   353      */
   354     @JavaScriptBody(args="a", body="return Math.ceil(a);")
   355     public static double ceil(double a) {
   356         throw new UnsupportedOperationException();
   357     }
   358 
   359     /**
   360      * Returns the largest (closest to positive infinity)
   361      * {@code double} value that is less than or equal to the
   362      * argument and is equal to a mathematical integer. Special cases:
   363      * <ul><li>If the argument value is already equal to a
   364      * mathematical integer, then the result is the same as the
   365      * argument.  <li>If the argument is NaN or an infinity or
   366      * positive zero or negative zero, then the result is the same as
   367      * the argument.</ul>
   368      *
   369      * @param   a   a value.
   370      * @return  the largest (closest to positive infinity)
   371      *          floating-point value that less than or equal to the argument
   372      *          and is equal to a mathematical integer.
   373      */
   374     @JavaScriptBody(args="a", body="return Math.floor(a);")
   375     public static double floor(double a) {
   376         throw new UnsupportedOperationException();
   377     }
   378 
   379     /**
   380      * Returns the angle <i>theta</i> from the conversion of rectangular
   381      * coordinates ({@code x},&nbsp;{@code y}) to polar
   382      * coordinates (r,&nbsp;<i>theta</i>).
   383      * This method computes the phase <i>theta</i> by computing an arc tangent
   384      * of {@code y/x} in the range of -<i>pi</i> to <i>pi</i>. Special
   385      * cases:
   386      * <ul><li>If either argument is NaN, then the result is NaN.
   387      * <li>If the first argument is positive zero and the second argument
   388      * is positive, or the first argument is positive and finite and the
   389      * second argument is positive infinity, then the result is positive
   390      * zero.
   391      * <li>If the first argument is negative zero and the second argument
   392      * is positive, or the first argument is negative and finite and the
   393      * second argument is positive infinity, then the result is negative zero.
   394      * <li>If the first argument is positive zero and the second argument
   395      * is negative, or the first argument is positive and finite and the
   396      * second argument is negative infinity, then the result is the
   397      * {@code double} value closest to <i>pi</i>.
   398      * <li>If the first argument is negative zero and the second argument
   399      * is negative, or the first argument is negative and finite and the
   400      * second argument is negative infinity, then the result is the
   401      * {@code double} value closest to -<i>pi</i>.
   402      * <li>If the first argument is positive and the second argument is
   403      * positive zero or negative zero, or the first argument is positive
   404      * infinity and the second argument is finite, then the result is the
   405      * {@code double} value closest to <i>pi</i>/2.
   406      * <li>If the first argument is negative and the second argument is
   407      * positive zero or negative zero, or the first argument is negative
   408      * infinity and the second argument is finite, then the result is the
   409      * {@code double} value closest to -<i>pi</i>/2.
   410      * <li>If both arguments are positive infinity, then the result is the
   411      * {@code double} value closest to <i>pi</i>/4.
   412      * <li>If the first argument is positive infinity and the second argument
   413      * is negative infinity, then the result is the {@code double}
   414      * value closest to 3*<i>pi</i>/4.
   415      * <li>If the first argument is negative infinity and the second argument
   416      * is positive infinity, then the result is the {@code double} value
   417      * closest to -<i>pi</i>/4.
   418      * <li>If both arguments are negative infinity, then the result is the
   419      * {@code double} value closest to -3*<i>pi</i>/4.</ul>
   420      *
   421      * <p>The computed result must be within 2 ulps of the exact result.
   422      * Results must be semi-monotonic.
   423      *
   424      * @param   y   the ordinate coordinate
   425      * @param   x   the abscissa coordinate
   426      * @return  the <i>theta</i> component of the point
   427      *          (<i>r</i>,&nbsp;<i>theta</i>)
   428      *          in polar coordinates that corresponds to the point
   429      *          (<i>x</i>,&nbsp;<i>y</i>) in Cartesian coordinates.
   430      */
   431     @JavaScriptBody(args={"y", "x"}, body="return Math.atan2(y, x);")
   432     public static double atan2(double y, double x) {
   433         throw new UnsupportedOperationException();
   434     }
   435 
   436     /**
   437      * Returns the value of the first argument raised to the power of the
   438      * second argument. Special cases:
   439      *
   440      * <ul><li>If the second argument is positive or negative zero, then the
   441      * result is 1.0.
   442      * <li>If the second argument is 1.0, then the result is the same as the
   443      * first argument.
   444      * <li>If the second argument is NaN, then the result is NaN.
   445      * <li>If the first argument is NaN and the second argument is nonzero,
   446      * then the result is NaN.
   447      *
   448      * <li>If
   449      * <ul>
   450      * <li>the absolute value of the first argument is greater than 1
   451      * and the second argument is positive infinity, or
   452      * <li>the absolute value of the first argument is less than 1 and
   453      * the second argument is negative infinity,
   454      * </ul>
   455      * then the result is positive infinity.
   456      *
   457      * <li>If
   458      * <ul>
   459      * <li>the absolute value of the first argument is greater than 1 and
   460      * the second argument is negative infinity, or
   461      * <li>the absolute value of the
   462      * first argument is less than 1 and the second argument is positive
   463      * infinity,
   464      * </ul>
   465      * then the result is positive zero.
   466      *
   467      * <li>If the absolute value of the first argument equals 1 and the
   468      * second argument is infinite, then the result is NaN.
   469      *
   470      * <li>If
   471      * <ul>
   472      * <li>the first argument is positive zero and the second argument
   473      * is greater than zero, or
   474      * <li>the first argument is positive infinity and the second
   475      * argument is less than zero,
   476      * </ul>
   477      * then the result is positive zero.
   478      *
   479      * <li>If
   480      * <ul>
   481      * <li>the first argument is positive zero and the second argument
   482      * is less than zero, or
   483      * <li>the first argument is positive infinity and the second
   484      * argument is greater than zero,
   485      * </ul>
   486      * then the result is positive infinity.
   487      *
   488      * <li>If
   489      * <ul>
   490      * <li>the first argument is negative zero and the second argument
   491      * is greater than zero but not a finite odd integer, or
   492      * <li>the first argument is negative infinity and the second
   493      * argument is less than zero but not a finite odd integer,
   494      * </ul>
   495      * then the result is positive zero.
   496      *
   497      * <li>If
   498      * <ul>
   499      * <li>the first argument is negative zero and the second argument
   500      * is a positive finite odd integer, or
   501      * <li>the first argument is negative infinity and the second
   502      * argument is a negative finite odd integer,
   503      * </ul>
   504      * then the result is negative zero.
   505      *
   506      * <li>If
   507      * <ul>
   508      * <li>the first argument is negative zero and the second argument
   509      * is less than zero but not a finite odd integer, or
   510      * <li>the first argument is negative infinity and the second
   511      * argument is greater than zero but not a finite odd integer,
   512      * </ul>
   513      * then the result is positive infinity.
   514      *
   515      * <li>If
   516      * <ul>
   517      * <li>the first argument is negative zero and the second argument
   518      * is a negative finite odd integer, or
   519      * <li>the first argument is negative infinity and the second
   520      * argument is a positive finite odd integer,
   521      * </ul>
   522      * then the result is negative infinity.
   523      *
   524      * <li>If the first argument is finite and less than zero
   525      * <ul>
   526      * <li> if the second argument is a finite even integer, the
   527      * result is equal to the result of raising the absolute value of
   528      * the first argument to the power of the second argument
   529      *
   530      * <li>if the second argument is a finite odd integer, the result
   531      * is equal to the negative of the result of raising the absolute
   532      * value of the first argument to the power of the second
   533      * argument
   534      *
   535      * <li>if the second argument is finite and not an integer, then
   536      * the result is NaN.
   537      * </ul>
   538      *
   539      * <li>If both arguments are integers, then the result is exactly equal
   540      * to the mathematical result of raising the first argument to the power
   541      * of the second argument if that result can in fact be represented
   542      * exactly as a {@code double} value.</ul>
   543      *
   544      * <p>(In the foregoing descriptions, a floating-point value is
   545      * considered to be an integer if and only if it is finite and a
   546      * fixed point of the method {@link #ceil ceil} or,
   547      * equivalently, a fixed point of the method {@link #floor
   548      * floor}. A value is a fixed point of a one-argument
   549      * method if and only if the result of applying the method to the
   550      * value is equal to the value.)
   551      *
   552      * <p>The computed result must be within 1 ulp of the exact result.
   553      * Results must be semi-monotonic.
   554      *
   555      * @param   a   the base.
   556      * @param   b   the exponent.
   557      * @return  the value {@code a}<sup>{@code b}</sup>.
   558      */
   559     @JavaScriptBody(args={"a", "b"}, body="return Math.pow(a, b);")
   560     public static double pow(double a, double b) {
   561         throw new UnsupportedOperationException();
   562     }
   563 
   564     /**
   565      * Returns the closest {@code int} to the argument, with ties
   566      * rounding up.
   567      *
   568      * <p>
   569      * Special cases:
   570      * <ul><li>If the argument is NaN, the result is 0.
   571      * <li>If the argument is negative infinity or any value less than or
   572      * equal to the value of {@code Integer.MIN_VALUE}, the result is
   573      * equal to the value of {@code Integer.MIN_VALUE}.
   574      * <li>If the argument is positive infinity or any value greater than or
   575      * equal to the value of {@code Integer.MAX_VALUE}, the result is
   576      * equal to the value of {@code Integer.MAX_VALUE}.</ul>
   577      *
   578      * @param   a   a floating-point value to be rounded to an integer.
   579      * @return  the value of the argument rounded to the nearest
   580      *          {@code int} value.
   581      * @see     java.lang.Integer#MAX_VALUE
   582      * @see     java.lang.Integer#MIN_VALUE
   583      */
   584     @JavaScriptBody(args="a", body="return Math.round(a);")
   585     public static int round(float a) {
   586         throw new UnsupportedOperationException();
   587     }
   588 
   589     /**
   590      * Returns the closest {@code long} to the argument, with ties
   591      * rounding up.
   592      *
   593      * <p>Special cases:
   594      * <ul><li>If the argument is NaN, the result is 0.
   595      * <li>If the argument is negative infinity or any value less than or
   596      * equal to the value of {@code Long.MIN_VALUE}, the result is
   597      * equal to the value of {@code Long.MIN_VALUE}.
   598      * <li>If the argument is positive infinity or any value greater than or
   599      * equal to the value of {@code Long.MAX_VALUE}, the result is
   600      * equal to the value of {@code Long.MAX_VALUE}.</ul>
   601      *
   602      * @param   a   a floating-point value to be rounded to a
   603      *          {@code long}.
   604      * @return  the value of the argument rounded to the nearest
   605      *          {@code long} value.
   606      * @see     java.lang.Long#MAX_VALUE
   607      * @see     java.lang.Long#MIN_VALUE
   608      */
   609     @JavaScriptBody(args="a", body="return Math.round(a);")
   610     public static long round(double a) {
   611         throw new UnsupportedOperationException();
   612     }
   613 
   614 //    private static Random randomNumberGenerator;
   615 //
   616 //    private static synchronized Random initRNG() {
   617 //        Random rnd = randomNumberGenerator;
   618 //        return (rnd == null) ? (randomNumberGenerator = new Random()) : rnd;
   619 //    }
   620 
   621     /**
   622      * Returns a {@code double} value with a positive sign, greater
   623      * than or equal to {@code 0.0} and less than {@code 1.0}.
   624      * Returned values are chosen pseudorandomly with (approximately)
   625      * uniform distribution from that range.
   626      *
   627      * <p>When this method is first called, it creates a single new
   628      * pseudorandom-number generator, exactly as if by the expression
   629      *
   630      * <blockquote>{@code new java.util.Random()}</blockquote>
   631      *
   632      * This new pseudorandom-number generator is used thereafter for
   633      * all calls to this method and is used nowhere else.
   634      *
   635      * <p>This method is properly synchronized to allow correct use by
   636      * more than one thread. However, if many threads need to generate
   637      * pseudorandom numbers at a great rate, it may reduce contention
   638      * for each thread to have its own pseudorandom-number generator.
   639      *
   640      * @return  a pseudorandom {@code double} greater than or equal
   641      * to {@code 0.0} and less than {@code 1.0}.
   642      * @see Random#nextDouble()
   643      */
   644     @JavaScriptBody(args={}, body="return Math.random();")
   645     public static double random() {
   646         throw new UnsupportedOperationException();
   647     }
   648 
   649     /**
   650      * Returns the absolute value of an {@code int} value.
   651      * If the argument is not negative, the argument is returned.
   652      * If the argument is negative, the negation of the argument is returned.
   653      *
   654      * <p>Note that if the argument is equal to the value of
   655      * {@link Integer#MIN_VALUE}, the most negative representable
   656      * {@code int} value, the result is that same value, which is
   657      * negative.
   658      *
   659      * @param   a   the argument whose absolute value is to be determined
   660      * @return  the absolute value of the argument.
   661      */
   662     public static int abs(int a) {
   663         return (a < 0) ? -a : a;
   664     }
   665 
   666     /**
   667      * Returns the absolute value of a {@code long} value.
   668      * If the argument is not negative, the argument is returned.
   669      * If the argument is negative, the negation of the argument is returned.
   670      *
   671      * <p>Note that if the argument is equal to the value of
   672      * {@link Long#MIN_VALUE}, the most negative representable
   673      * {@code long} value, the result is that same value, which
   674      * is negative.
   675      *
   676      * @param   a   the argument whose absolute value is to be determined
   677      * @return  the absolute value of the argument.
   678      */
   679     public static long abs(long a) {
   680         return (a < 0) ? -a : a;
   681     }
   682 
   683     /**
   684      * Returns the absolute value of a {@code float} value.
   685      * If the argument is not negative, the argument is returned.
   686      * If the argument is negative, the negation of the argument is returned.
   687      * Special cases:
   688      * <ul><li>If the argument is positive zero or negative zero, the
   689      * result is positive zero.
   690      * <li>If the argument is infinite, the result is positive infinity.
   691      * <li>If the argument is NaN, the result is NaN.</ul>
   692      * In other words, the result is the same as the value of the expression:
   693      * <p>{@code Float.intBitsToFloat(0x7fffffff & Float.floatToIntBits(a))}
   694      *
   695      * @param   a   the argument whose absolute value is to be determined
   696      * @return  the absolute value of the argument.
   697      */
   698     public static float abs(float a) {
   699         return (a <= 0.0F) ? 0.0F - a : a;
   700     }
   701 
   702     /**
   703      * Returns the absolute value of a {@code double} value.
   704      * If the argument is not negative, the argument is returned.
   705      * If the argument is negative, the negation of the argument is returned.
   706      * Special cases:
   707      * <ul><li>If the argument is positive zero or negative zero, the result
   708      * is positive zero.
   709      * <li>If the argument is infinite, the result is positive infinity.
   710      * <li>If the argument is NaN, the result is NaN.</ul>
   711      * In other words, the result is the same as the value of the expression:
   712      * <p>{@code Double.longBitsToDouble((Double.doubleToLongBits(a)<<1)>>>1)}
   713      *
   714      * @param   a   the argument whose absolute value is to be determined
   715      * @return  the absolute value of the argument.
   716      */
   717     public static double abs(double a) {
   718         return (a <= 0.0D) ? 0.0D - a : a;
   719     }
   720 
   721     /**
   722      * Returns the greater of two {@code int} values. That is, the
   723      * result is the argument closer to the value of
   724      * {@link Integer#MAX_VALUE}. If the arguments have the same value,
   725      * the result is that same value.
   726      *
   727      * @param   a   an argument.
   728      * @param   b   another argument.
   729      * @return  the larger of {@code a} and {@code b}.
   730      */
   731     public static int max(int a, int b) {
   732         return (a >= b) ? a : b;
   733     }
   734 
   735     /**
   736      * Returns the greater of two {@code long} values. That is, the
   737      * result is the argument closer to the value of
   738      * {@link Long#MAX_VALUE}. If the arguments have the same value,
   739      * the result is that same value.
   740      *
   741      * @param   a   an argument.
   742      * @param   b   another argument.
   743      * @return  the larger of {@code a} and {@code b}.
   744      */
   745     public static long max(long a, long b) {
   746         return (a >= b) ? a : b;
   747     }
   748 
   749     /**
   750      * Returns the greater of two {@code float} values.  That is,
   751      * the result is the argument closer to positive infinity. If the
   752      * arguments have the same value, the result is that same
   753      * value. If either value is NaN, then the result is NaN.  Unlike
   754      * the numerical comparison operators, this method considers
   755      * negative zero to be strictly smaller than positive zero. If one
   756      * argument is positive zero and the other negative zero, the
   757      * result is positive zero.
   758      *
   759      * @param   a   an argument.
   760      * @param   b   another argument.
   761      * @return  the larger of {@code a} and {@code b}.
   762      */
   763     @JavaScriptBody(args={"a", "b"},
   764         body="return Math.max(a,b);"
   765     )
   766     public static float max(float a, float b) {
   767         throw new UnsupportedOperationException();
   768     }
   769 
   770     /**
   771      * Returns the greater of two {@code double} values.  That
   772      * is, the result is the argument closer to positive infinity. If
   773      * the arguments have the same value, the result is that same
   774      * value. If either value is NaN, then the result is NaN.  Unlike
   775      * the numerical comparison operators, this method considers
   776      * negative zero to be strictly smaller than positive zero. If one
   777      * argument is positive zero and the other negative zero, the
   778      * result is positive zero.
   779      *
   780      * @param   a   an argument.
   781      * @param   b   another argument.
   782      * @return  the larger of {@code a} and {@code b}.
   783      */
   784     @JavaScriptBody(args={"a", "b"},
   785         body="return Math.max(a,b);"
   786     )
   787     public static double max(double a, double b) {
   788         throw new UnsupportedOperationException();
   789     }
   790 
   791     /**
   792      * Returns the smaller of two {@code int} values. That is,
   793      * the result the argument closer to the value of
   794      * {@link Integer#MIN_VALUE}.  If the arguments have the same
   795      * value, the result is that same value.
   796      *
   797      * @param   a   an argument.
   798      * @param   b   another argument.
   799      * @return  the smaller of {@code a} and {@code b}.
   800      */
   801     public static int min(int a, int b) {
   802         return (a <= b) ? a : b;
   803     }
   804 
   805     /**
   806      * Returns the smaller of two {@code long} values. That is,
   807      * the result is the argument closer to the value of
   808      * {@link Long#MIN_VALUE}. If the arguments have the same
   809      * value, the result is that same value.
   810      *
   811      * @param   a   an argument.
   812      * @param   b   another argument.
   813      * @return  the smaller of {@code a} and {@code b}.
   814      */
   815     public static long min(long a, long b) {
   816         return (a <= b) ? a : b;
   817     }
   818 
   819     /**
   820      * Returns the smaller of two {@code float} values.  That is,
   821      * the result is the value closer to negative infinity. If the
   822      * arguments have the same value, the result is that same
   823      * value. If either value is NaN, then the result is NaN.  Unlike
   824      * the numerical comparison operators, this method considers
   825      * negative zero to be strictly smaller than positive zero.  If
   826      * one argument is positive zero and the other is negative zero,
   827      * the result is negative zero.
   828      *
   829      * @param   a   an argument.
   830      * @param   b   another argument.
   831      * @return  the smaller of {@code a} and {@code b}.
   832      */
   833     @JavaScriptBody(args={"a", "b"},
   834         body="return Math.min(a,b);"
   835     )
   836     public static float min(float a, float b) {
   837         throw new UnsupportedOperationException();
   838     }
   839 
   840     /**
   841      * Returns the smaller of two {@code double} values.  That
   842      * is, the result is the value closer to negative infinity. If the
   843      * arguments have the same value, the result is that same
   844      * value. If either value is NaN, then the result is NaN.  Unlike
   845      * the numerical comparison operators, this method considers
   846      * negative zero to be strictly smaller than positive zero. If one
   847      * argument is positive zero and the other is negative zero, the
   848      * result is negative zero.
   849      *
   850      * @param   a   an argument.
   851      * @param   b   another argument.
   852      * @return  the smaller of {@code a} and {@code b}.
   853      */
   854     @JavaScriptBody(args={"a", "b"},
   855         body="return Math.min(a,b);"
   856     )
   857     public static double min(double a, double b) {
   858         throw new UnsupportedOperationException();
   859     }
   860 
   861     /**
   862      * Returns the size of an ulp of the argument.  An ulp of a
   863      * {@code double} value is the positive distance between this
   864      * floating-point value and the {@code double} value next
   865      * larger in magnitude.  Note that for non-NaN <i>x</i>,
   866      * <code>ulp(-<i>x</i>) == ulp(<i>x</i>)</code>.
   867      *
   868      * <p>Special Cases:
   869      * <ul>
   870      * <li> If the argument is NaN, then the result is NaN.
   871      * <li> If the argument is positive or negative infinity, then the
   872      * result is positive infinity.
   873      * <li> If the argument is positive or negative zero, then the result is
   874      * {@code Double.MIN_VALUE}.
   875      * <li> If the argument is &plusmn;{@code Double.MAX_VALUE}, then
   876      * the result is equal to 2<sup>971</sup>.
   877      * </ul>
   878      *
   879      * @param d the floating-point value whose ulp is to be returned
   880      * @return the size of an ulp of the argument
   881      * @author Joseph D. Darcy
   882      * @since 1.5
   883      */
   884 //    public static double ulp(double d) {
   885 //        return sun.misc.FpUtils.ulp(d);
   886 //    }
   887 
   888     /**
   889      * Returns the size of an ulp of the argument.  An ulp of a
   890      * {@code float} value is the positive distance between this
   891      * floating-point value and the {@code float} value next
   892      * larger in magnitude.  Note that for non-NaN <i>x</i>,
   893      * <code>ulp(-<i>x</i>) == ulp(<i>x</i>)</code>.
   894      *
   895      * <p>Special Cases:
   896      * <ul>
   897      * <li> If the argument is NaN, then the result is NaN.
   898      * <li> If the argument is positive or negative infinity, then the
   899      * result is positive infinity.
   900      * <li> If the argument is positive or negative zero, then the result is
   901      * {@code Float.MIN_VALUE}.
   902      * <li> If the argument is &plusmn;{@code Float.MAX_VALUE}, then
   903      * the result is equal to 2<sup>104</sup>.
   904      * </ul>
   905      *
   906      * @param f the floating-point value whose ulp is to be returned
   907      * @return the size of an ulp of the argument
   908      * @author Joseph D. Darcy
   909      * @since 1.5
   910      */
   911 //    public static float ulp(float f) {
   912 //        return sun.misc.FpUtils.ulp(f);
   913 //    }
   914 
   915     /**
   916      * Returns the signum function of the argument; zero if the argument
   917      * is zero, 1.0 if the argument is greater than zero, -1.0 if the
   918      * argument is less than zero.
   919      *
   920      * <p>Special Cases:
   921      * <ul>
   922      * <li> If the argument is NaN, then the result is NaN.
   923      * <li> If the argument is positive zero or negative zero, then the
   924      *      result is the same as the argument.
   925      * </ul>
   926      *
   927      * @param d the floating-point value whose signum is to be returned
   928      * @return the signum function of the argument
   929      * @author Joseph D. Darcy
   930      * @since 1.5
   931      */
   932 //    public static double signum(double d) {
   933 //        return sun.misc.FpUtils.signum(d);
   934 //    }
   935 
   936     /**
   937      * Returns the signum function of the argument; zero if the argument
   938      * is zero, 1.0f if the argument is greater than zero, -1.0f if the
   939      * argument is less than zero.
   940      *
   941      * <p>Special Cases:
   942      * <ul>
   943      * <li> If the argument is NaN, then the result is NaN.
   944      * <li> If the argument is positive zero or negative zero, then the
   945      *      result is the same as the argument.
   946      * </ul>
   947      *
   948      * @param f the floating-point value whose signum is to be returned
   949      * @return the signum function of the argument
   950      * @author Joseph D. Darcy
   951      * @since 1.5
   952      */
   953 //    public static float signum(float f) {
   954 //        return sun.misc.FpUtils.signum(f);
   955 //    }
   956 
   957     /**
   958      * Returns the first floating-point argument with the sign of the
   959      * second floating-point argument.  Note that unlike the {@link
   960      * StrictMath#copySign(double, double) StrictMath.copySign}
   961      * method, this method does not require NaN {@code sign}
   962      * arguments to be treated as positive values; implementations are
   963      * permitted to treat some NaN arguments as positive and other NaN
   964      * arguments as negative to allow greater performance.
   965      *
   966      * @param magnitude  the parameter providing the magnitude of the result
   967      * @param sign   the parameter providing the sign of the result
   968      * @return a value with the magnitude of {@code magnitude}
   969      * and the sign of {@code sign}.
   970      * @since 1.6
   971      */
   972 //    public static double copySign(double magnitude, double sign) {
   973 //        return sun.misc.FpUtils.rawCopySign(magnitude, sign);
   974 //    }
   975 
   976     /**
   977      * Returns the first floating-point argument with the sign of the
   978      * second floating-point argument.  Note that unlike the {@link
   979      * StrictMath#copySign(float, float) StrictMath.copySign}
   980      * method, this method does not require NaN {@code sign}
   981      * arguments to be treated as positive values; implementations are
   982      * permitted to treat some NaN arguments as positive and other NaN
   983      * arguments as negative to allow greater performance.
   984      *
   985      * @param magnitude  the parameter providing the magnitude of the result
   986      * @param sign   the parameter providing the sign of the result
   987      * @return a value with the magnitude of {@code magnitude}
   988      * and the sign of {@code sign}.
   989      * @since 1.6
   990      */
   991 //    public static float copySign(float magnitude, float sign) {
   992 //        return sun.misc.FpUtils.rawCopySign(magnitude, sign);
   993 //    }
   994 
   995     /**
   996      * Returns the unbiased exponent used in the representation of a
   997      * {@code float}.  Special cases:
   998      *
   999      * <ul>
  1000      * <li>If the argument is NaN or infinite, then the result is
  1001      * {@link Float#MAX_EXPONENT} + 1.
  1002      * <li>If the argument is zero or subnormal, then the result is
  1003      * {@link Float#MIN_EXPONENT} -1.
  1004      * </ul>
  1005      * @param f a {@code float} value
  1006      * @return the unbiased exponent of the argument
  1007      * @since 1.6
  1008      */
  1009 //    public static int getExponent(float f) {
  1010 //        return sun.misc.FpUtils.getExponent(f);
  1011 //    }
  1012 
  1013     /**
  1014      * Returns the unbiased exponent used in the representation of a
  1015      * {@code double}.  Special cases:
  1016      *
  1017      * <ul>
  1018      * <li>If the argument is NaN or infinite, then the result is
  1019      * {@link Double#MAX_EXPONENT} + 1.
  1020      * <li>If the argument is zero or subnormal, then the result is
  1021      * {@link Double#MIN_EXPONENT} -1.
  1022      * </ul>
  1023      * @param d a {@code double} value
  1024      * @return the unbiased exponent of the argument
  1025      * @since 1.6
  1026      */
  1027 //    public static int getExponent(double d) {
  1028 //        return sun.misc.FpUtils.getExponent(d);
  1029 //    }
  1030 
  1031     /**
  1032      * Returns the floating-point number adjacent to the first
  1033      * argument in the direction of the second argument.  If both
  1034      * arguments compare as equal the second argument is returned.
  1035      *
  1036      * <p>
  1037      * Special cases:
  1038      * <ul>
  1039      * <li> If either argument is a NaN, then NaN is returned.
  1040      *
  1041      * <li> If both arguments are signed zeros, {@code direction}
  1042      * is returned unchanged (as implied by the requirement of
  1043      * returning the second argument if the arguments compare as
  1044      * equal).
  1045      *
  1046      * <li> If {@code start} is
  1047      * &plusmn;{@link Double#MIN_VALUE} and {@code direction}
  1048      * has a value such that the result should have a smaller
  1049      * magnitude, then a zero with the same sign as {@code start}
  1050      * is returned.
  1051      *
  1052      * <li> If {@code start} is infinite and
  1053      * {@code direction} has a value such that the result should
  1054      * have a smaller magnitude, {@link Double#MAX_VALUE} with the
  1055      * same sign as {@code start} is returned.
  1056      *
  1057      * <li> If {@code start} is equal to &plusmn;
  1058      * {@link Double#MAX_VALUE} and {@code direction} has a
  1059      * value such that the result should have a larger magnitude, an
  1060      * infinity with same sign as {@code start} is returned.
  1061      * </ul>
  1062      *
  1063      * @param start  starting floating-point value
  1064      * @param direction value indicating which of
  1065      * {@code start}'s neighbors or {@code start} should
  1066      * be returned
  1067      * @return The floating-point number adjacent to {@code start} in the
  1068      * direction of {@code direction}.
  1069      * @since 1.6
  1070      */
  1071 //    public static double nextAfter(double start, double direction) {
  1072 //        return sun.misc.FpUtils.nextAfter(start, direction);
  1073 //    }
  1074 
  1075     /**
  1076      * Returns the floating-point number adjacent to the first
  1077      * argument in the direction of the second argument.  If both
  1078      * arguments compare as equal a value equivalent to the second argument
  1079      * is returned.
  1080      *
  1081      * <p>
  1082      * Special cases:
  1083      * <ul>
  1084      * <li> If either argument is a NaN, then NaN is returned.
  1085      *
  1086      * <li> If both arguments are signed zeros, a value equivalent
  1087      * to {@code direction} is returned.
  1088      *
  1089      * <li> If {@code start} is
  1090      * &plusmn;{@link Float#MIN_VALUE} and {@code direction}
  1091      * has a value such that the result should have a smaller
  1092      * magnitude, then a zero with the same sign as {@code start}
  1093      * is returned.
  1094      *
  1095      * <li> If {@code start} is infinite and
  1096      * {@code direction} has a value such that the result should
  1097      * have a smaller magnitude, {@link Float#MAX_VALUE} with the
  1098      * same sign as {@code start} is returned.
  1099      *
  1100      * <li> If {@code start} is equal to &plusmn;
  1101      * {@link Float#MAX_VALUE} and {@code direction} has a
  1102      * value such that the result should have a larger magnitude, an
  1103      * infinity with same sign as {@code start} is returned.
  1104      * </ul>
  1105      *
  1106      * @param start  starting floating-point value
  1107      * @param direction value indicating which of
  1108      * {@code start}'s neighbors or {@code start} should
  1109      * be returned
  1110      * @return The floating-point number adjacent to {@code start} in the
  1111      * direction of {@code direction}.
  1112      * @since 1.6
  1113      */
  1114 //    public static float nextAfter(float start, double direction) {
  1115 //        return sun.misc.FpUtils.nextAfter(start, direction);
  1116 //    }
  1117 
  1118     /**
  1119      * Returns the floating-point value adjacent to {@code d} in
  1120      * the direction of positive infinity.  This method is
  1121      * semantically equivalent to {@code nextAfter(d,
  1122      * Double.POSITIVE_INFINITY)}; however, a {@code nextUp}
  1123      * implementation may run faster than its equivalent
  1124      * {@code nextAfter} call.
  1125      *
  1126      * <p>Special Cases:
  1127      * <ul>
  1128      * <li> If the argument is NaN, the result is NaN.
  1129      *
  1130      * <li> If the argument is positive infinity, the result is
  1131      * positive infinity.
  1132      *
  1133      * <li> If the argument is zero, the result is
  1134      * {@link Double#MIN_VALUE}
  1135      *
  1136      * </ul>
  1137      *
  1138      * @param d starting floating-point value
  1139      * @return The adjacent floating-point value closer to positive
  1140      * infinity.
  1141      * @since 1.6
  1142      */
  1143 //    public static double nextUp(double d) {
  1144 //        return sun.misc.FpUtils.nextUp(d);
  1145 //    }
  1146 
  1147     /**
  1148      * Returns the floating-point value adjacent to {@code f} in
  1149      * the direction of positive infinity.  This method is
  1150      * semantically equivalent to {@code nextAfter(f,
  1151      * Float.POSITIVE_INFINITY)}; however, a {@code nextUp}
  1152      * implementation may run faster than its equivalent
  1153      * {@code nextAfter} call.
  1154      *
  1155      * <p>Special Cases:
  1156      * <ul>
  1157      * <li> If the argument is NaN, the result is NaN.
  1158      *
  1159      * <li> If the argument is positive infinity, the result is
  1160      * positive infinity.
  1161      *
  1162      * <li> If the argument is zero, the result is
  1163      * {@link Float#MIN_VALUE}
  1164      *
  1165      * </ul>
  1166      *
  1167      * @param f starting floating-point value
  1168      * @return The adjacent floating-point value closer to positive
  1169      * infinity.
  1170      * @since 1.6
  1171      */
  1172 //    public static float nextUp(float f) {
  1173 //        return sun.misc.FpUtils.nextUp(f);
  1174 //    }
  1175 
  1176 
  1177     /**
  1178      * Return {@code d} &times;
  1179      * 2<sup>{@code scaleFactor}</sup> rounded as if performed
  1180      * by a single correctly rounded floating-point multiply to a
  1181      * member of the double value set.  See the Java
  1182      * Language Specification for a discussion of floating-point
  1183      * value sets.  If the exponent of the result is between {@link
  1184      * Double#MIN_EXPONENT} and {@link Double#MAX_EXPONENT}, the
  1185      * answer is calculated exactly.  If the exponent of the result
  1186      * would be larger than {@code Double.MAX_EXPONENT}, an
  1187      * infinity is returned.  Note that if the result is subnormal,
  1188      * precision may be lost; that is, when {@code scalb(x, n)}
  1189      * is subnormal, {@code scalb(scalb(x, n), -n)} may not equal
  1190      * <i>x</i>.  When the result is non-NaN, the result has the same
  1191      * sign as {@code d}.
  1192      *
  1193      * <p>Special cases:
  1194      * <ul>
  1195      * <li> If the first argument is NaN, NaN is returned.
  1196      * <li> If the first argument is infinite, then an infinity of the
  1197      * same sign is returned.
  1198      * <li> If the first argument is zero, then a zero of the same
  1199      * sign is returned.
  1200      * </ul>
  1201      *
  1202      * @param d number to be scaled by a power of two.
  1203      * @param scaleFactor power of 2 used to scale {@code d}
  1204      * @return {@code d} &times; 2<sup>{@code scaleFactor}</sup>
  1205      * @since 1.6
  1206      */
  1207 //    public static double scalb(double d, int scaleFactor) {
  1208 //        return sun.misc.FpUtils.scalb(d, scaleFactor);
  1209 //    }
  1210 
  1211     /**
  1212      * Return {@code f} &times;
  1213      * 2<sup>{@code scaleFactor}</sup> rounded as if performed
  1214      * by a single correctly rounded floating-point multiply to a
  1215      * member of the float value set.  See the Java
  1216      * Language Specification for a discussion of floating-point
  1217      * value sets.  If the exponent of the result is between {@link
  1218      * Float#MIN_EXPONENT} and {@link Float#MAX_EXPONENT}, the
  1219      * answer is calculated exactly.  If the exponent of the result
  1220      * would be larger than {@code Float.MAX_EXPONENT}, an
  1221      * infinity is returned.  Note that if the result is subnormal,
  1222      * precision may be lost; that is, when {@code scalb(x, n)}
  1223      * is subnormal, {@code scalb(scalb(x, n), -n)} may not equal
  1224      * <i>x</i>.  When the result is non-NaN, the result has the same
  1225      * sign as {@code f}.
  1226      *
  1227      * <p>Special cases:
  1228      * <ul>
  1229      * <li> If the first argument is NaN, NaN is returned.
  1230      * <li> If the first argument is infinite, then an infinity of the
  1231      * same sign is returned.
  1232      * <li> If the first argument is zero, then a zero of the same
  1233      * sign is returned.
  1234      * </ul>
  1235      *
  1236      * @param f number to be scaled by a power of two.
  1237      * @param scaleFactor power of 2 used to scale {@code f}
  1238      * @return {@code f} &times; 2<sup>{@code scaleFactor}</sup>
  1239      * @since 1.6
  1240      */
  1241 //    public static float scalb(float f, int scaleFactor) {
  1242 //        return sun.misc.FpUtils.scalb(f, scaleFactor);
  1243 //    }
  1244 }