/* -*- Mode: java; tab-width: 4; indent-tabs-mode: 1; c-basic-offset: 4 -*- * * The contents of this file are subject to the Netscape Public * License Version 1.1 (the "License"); you may not use this file * except in compliance with the License. You may obtain a copy of * the License at http://www.mozilla.org/NPL/ * * Software distributed under the License is distributed on an "AS * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or * implied. See the License for the specific language governing * rights and limitations under the License. * * The Original Code is Rhino code, released * May 6, 1999. * * The Initial Developer of the Original Code is Netscape * Communications Corporation.  Portions created by Netscape are * Copyright (C) 1997-1999 Netscape Communications Corporation. All * Rights Reserved. * * Contributor(s): * Norris Boyd * Igor Bukanov * * Alternatively, the contents of this file may be used under the * terms of the GNU Public License (the "GPL"), in which case the * provisions of the GPL are applicable instead of those above. * If you wish to allow use of your version of this file only * under the terms of the GPL and not to allow others to use your * version of this file under the NPL, indicate your decision by * deleting the provisions above and replace them with the notice * and other provisions required by the GPL.  If you do not delete * the provisions above, a recipient may use your version of this * file under either the NPL or the GPL. */package org.mozilla.javascript;/** * This class implements the Math native object. * See ECMA 15.8. * @author Norris Boyd */final class NativeMath extends IdScriptableObject{    static final long serialVersionUID = -8838847185801131569L;    private static final Object MATH_TAG = new Object();    static void init(Scriptable scope, boolean sealed)    {        NativeMath obj = new NativeMath();        obj.activatePrototypeMap(MAX_ID);        obj.setPrototype(getObjectPrototype(scope));        obj.setParentScope(scope);        if (sealed) { obj.sealObject(); }        ScriptableObject.defineProperty(scope, "Math", obj,                                        ScriptableObject.DONTENUM);    }    private NativeMath()    {    }    public String getClassName() { return "Math"; }    protected void initPrototypeId(int id)    {        if (id <= LAST_METHOD_ID) {            String name;            int arity;            switch (id) {              case Id_toSource: arity = 0; name = "toSource"; break;              case Id_abs:      arity = 1; name = "abs";      break;              case Id_acos:     arity = 1; name = "acos";     break;              case Id_asin:     arity = 1; name = "asin";     break;              case Id_atan:     arity = 1; name = "atan";     break;              case Id_atan2:    arity = 2; name = "atan2";    break;              case Id_ceil:     arity = 1; name = "ceil";     break;              case Id_cos:      arity = 1; name = "cos";      break;              case Id_exp:      arity = 1; name = "exp";      break;              case Id_floor:    arity = 1; name = "floor";    break;              case Id_log:      arity = 1; name = "log";      break;              case Id_max:      arity = 2; name = "max";      break;              case Id_min:      arity = 2; name = "min";      break;              case Id_pow:      arity = 2; name = "pow";      break;              case Id_random:   arity = 0; name = "random";   break;              case Id_round:    arity = 1; name = "round";    break;              case Id_sin:      arity = 1; name = "sin";      break;              case Id_sqrt:     arity = 1; name = "sqrt";     break;              case Id_tan:      arity = 1; name = "tan";      break;              default: throw new IllegalStateException(String.valueOf(id));            }            initPrototypeMethod(MATH_TAG, id, name, arity);        } else {            String name;            double x;            switch (id) {              case Id_E:       x = Math.E;             name = "E";       break;              case Id_PI:      x = Math.PI;            name = "PI";      break;              case Id_LN10:    x = 2.302585092994046;  name = "LN10";    break;              case Id_LN2:     x = 0.6931471805599453; name = "LN2";     break;              case Id_LOG2E:   x = 1.4426950408889634; name = "LOG2E";   break;              case Id_LOG10E:  x = 0.4342944819032518; name = "LOG10E";  break;              case Id_SQRT1_2: x = 0.7071067811865476; name = "SQRT1_2"; break;              case Id_SQRT2:   x = 1.4142135623730951; name = "SQRT2";   break;              default: throw new IllegalStateException(String.valueOf(id));            }            initPrototypeValue(id, name, ScriptRuntime.wrapNumber(x),                               DONTENUM | READONLY | PERMANENT);        }    }    public Object execIdCall(IdFunctionObject f, Context cx, Scriptable scope,                             Scriptable thisObj, Object[] args)    {        if (!f.hasTag(MATH_TAG)) {            return super.execIdCall(f, cx, scope, thisObj, args);        }        double x;        int methodId = f.methodId();        switch (methodId) {            case Id_toSource:                return "Math";            case Id_abs:                x = ScriptRuntime.toNumber(args, 0);                // abs(-0.0) should be 0.0, but -0.0 < 0.0 == false                x = (x == 0.0) ? 0.0 : (x < 0.0) ? -x : x;                break;            case Id_acos:            case Id_asin:                x = ScriptRuntime.toNumber(args, 0);                if (x == x && -1.0 <= x && x <= 1.0) {                    x = (methodId == Id_acos) ? Math.acos(x) : Math.asin(x);                } else {                    x = Double.NaN;                }                break;            case Id_atan:                x = ScriptRuntime.toNumber(args, 0);                x = Math.atan(x);                break;            case Id_atan2:                x = ScriptRuntime.toNumber(args, 0);                x = Math.atan2(x, ScriptRuntime.toNumber(args, 1));                break;            case Id_ceil:                x = ScriptRuntime.toNumber(args, 0);                x = Math.ceil(x);                break;            case Id_cos:                x = ScriptRuntime.toNumber(args, 0);                x = (x == Double.POSITIVE_INFINITY                     || x == Double.NEGATIVE_INFINITY)                    ? Double.NaN : Math.cos(x);                break;            case Id_exp:                x = ScriptRuntime.toNumber(args, 0);                x = (x == Double.POSITIVE_INFINITY) ? x                    : (x == Double.NEGATIVE_INFINITY) ? 0.0                    : Math.exp(x);                break;            case Id_floor:                x = ScriptRuntime.toNumber(args, 0);                x = Math.floor(x);                break;            case Id_log:                x = ScriptRuntime.toNumber(args, 0);                // Java's log(<0) = -Infinity; we need NaN                x = (x < 0) ? Double.NaN : Math.log(x);                break;            case Id_max:            case Id_min:                x = (methodId == Id_max)                    ? Double.NEGATIVE_INFINITY : Double.POSITIVE_INFINITY;                for (int i = 0; i != args.length; ++i) {                    double d = ScriptRuntime.toNumber(args[i]);                    if (d != d) {                        x = d; // NaN                        break;                    }                    if (methodId == Id_max) {                        // if (x < d) x = d; does not work due to -0.0 >= +0.0                        x = Math.max(x, d);                    } else {                        x = Math.min(x, d);                    }                }