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1
28
29 package com.caucho.es;
30
31 import java.util.Random  ;
32
33
36 class NativeMath extends Native {
37 static final int ABS = 1;
38 static final int ACOS = 2;
39 static final int ASIN = 3;
40 static final int ATAN = 4;
41 static final int ATAN2 = 5;
42 static final int CEIL = 6;
43 static final int COS = 7;
44 static final int EXP = 8;
45 static final int FLOOR = 9;
46 static final int LOG = 10;
47 static final int MAX = 11;
48 static final int MIN = 12;
49 static final int POW = 13;
50 static final int RANDOM = 14;
51 static final int ROUND = 15;
52 static final int SET_SEED = 16;
53 static final int SIN = 17;
54 static final int SQRT = 18;
55 static final int TAN = 19;
56
57 Random random;
59
62 private NativeMath(String name, int n, int len)
63 {
64 super(name, len);
65
66 this.n = n;
67 }
68
69
72 static ESObject create(Global resin)
73 {
74 ESObject math = new ESObject("Math", null);
75
76 put(math, "abs", ABS, 1);
77 put(math, "asin", ASIN, 1);
78 put(math, "acos", ACOS, 1);
79 put(math, "atan", ATAN, 1);
80 put(math, "atan2", ATAN2, 2);
81 put(math, "ceil", CEIL, 1);
82 put(math, "cos", COS, 1);
83 put(math, "exp", EXP, 1);
84 put(math, "floor", FLOOR, 1);
85 put(math, "log", LOG, 1);
86 put(math, "max", MAX, 2);
87 put(math, "min", MIN, 2);
88 put(math, "pow", POW, 2);
89 put(math, "round", ROUND, 1);
90 put(math, "sin", SIN, 1);
91 put(math, "sqrt", SQRT, 1);
92 put(math, "tan", TAN, 1);
93 put(math, "random", RANDOM, 0);
94 put(math, "setSeed", SET_SEED, 1);
95
96 int flags = DONT_ENUM|DONT_DELETE|READ_ONLY;
97 math.put("E", ESNumber.create(Math.E), flags);
98 math.put("LN10", ESNumber.create(Math.log(10.0)), flags);
99 math.put("LN2", ESNumber.create(Math.log(2.0)), flags);
100 math.put("LOG2E", ESNumber.create(1.0 / Math.log(2.0)), flags);
101 math.put("LOG10E", ESNumber.create(1.0 / Math.log(10.0)), flags);
102 math.put("PI", ESNumber.create(Math.PI), flags);
103 math.put("SQRT1_2", ESNumber.create(Math.sqrt(0.5)), flags);
104 math.put("SQRT2", ESNumber.create(Math.sqrt(2.0)), flags);
105 Random random = new Random ();
107 try {
108 ((NativeMath) math.getProperty("random")).random = random;
109 ((NativeMath) math.getProperty("setSeed")).random = random;
110 } catch (Throwable e) {
111 }
112
113 math.setClean();
114
115 return math;
116 }
117
118 private static void put(ESObject obj, String name, int n, int length)
119 {
120 obj.put(name, new NativeMath(name, n, length), DONT_ENUM);
121 }
122
123 public ESBase call(Call eval, int length) throws Throwable
124 {
125 double arg;
126 double value;
127
128 switch (n) {
129 case ABS:
130 if (length == 0)
131 return esUndefined;
132 arg = eval.getArg(0).toNum();
133 return ESNumber.create(arg == 0 ? 0 : (arg < 0 ? -arg : arg));
134
135 case ACOS:
136 if (length == 0)
137 return esUndefined;
138 return ESNumber.create(Math.acos(eval.getArg(0).toNum()));
139
140 case ASIN:
141 if (length == 0)
142 return esUndefined;
143 return ESNumber.create(Math.asin(eval.getArg(0).toNum()));
144
145 case ATAN:
146 if (length == 0)
147 return esUndefined;
148 return ESNumber.create(Math.atan(eval.getArg(0).toNum()));
149
150 case ATAN2:
151 if (length < 2)
152 return esUndefined;
153 return ESNumber.create(Math.atan2(eval.getArg(0).toNum(),
154 eval.getArg(1).toNum()));
155
156 case CEIL:
157 if (length == 0)
158 return esUndefined;
159 return ESNumber.create(Math.ceil(eval.getArg(0).toNum()));
160
161 case COS:
162 if (length == 0)
163 return esUndefined;
164 return ESNumber.create(Math.cos(eval.getArg(0).toNum()));
165
166 case EXP:
167 if (length == 0)
168 return esUndefined;
169 return ESNumber.create(Math.exp(eval.getArg(0).toNum()));
170
171 case FLOOR:
172 if (length == 0)
173 return esUndefined;
174 return ESNumber.create(Math.floor(eval.getArg(0).toNum()));
175
176 case LOG:
177 if (length == 0)
178 return esUndefined;
179 return ESNumber.create(Math.log(eval.getArg(0).toNum()));
180
181 case MAX:
182 arg = -1.0/0.0;
183 for (int i = 0; i < length; i++) {
184 double v = eval.getArg(i).toNum();
185
186 arg = Math.max(v, arg);
187 }
188 return ESNumber.create(arg);
189
190 case MIN:
191 arg = 1.0/0.0;
192 for (int i = 0; i < length; i++) {
193 double v = eval.getArg(i).toNum();
194
195 arg = Math.min(v, arg);
196 }
197 return ESNumber.create(arg);
198
199 case POW:
200 if (length < 2)
201 return esUndefined;
202 return ESNumber.create(Math.pow(eval.getArg(0).toNum(),
203 eval.getArg(1).toNum()));
204
205 case RANDOM:
206 {
207 if (length > 1) {
208 int n = eval.getArg(0).toInt32();
209 if (n > 0)
210 return ESNumber.create((int) (random.nextDouble() * n));
211 } else {
212 return ESNumber.create(random.nextDouble());
213 }
214 }
215
216 case ROUND:
217 if (length == 0)
218 return esUndefined;
219
220 arg = eval.getArg(0).toNum();
221 if (arg >= -0.5 && arg < 0.5)
222 return ESNumber.create(Math.rint(arg));
223 else
224 return ESNumber.create(Math.floor(arg + 0.5));
225
226 case SET_SEED:
227 if (length != 0)
228 random.setSeed((long) eval.getArg(0).toNum());
229 return esUndefined;
230
231 case SIN:
232 if (length == 0)
233 return esUndefined;
234 return ESNumber.create(Math.sin(eval.getArg(0).toNum()));
235
236 case SQRT:
237 if (length == 0)
238 return esUndefined;
239 return ESNumber.create(Math.sqrt(eval.getArg(0).toNum()));
240
241 case TAN:
242 if (length == 0)
243 return esUndefined;
244 return ESNumber.create(Math.tan(eval.getArg(0).toNum()));
245
246 default:
247 throw new ESException("Undefined math function");
248 }
249 }
250 }
251 |
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