1
2 package org.xwt.js;
3
4 import org.xwt.util.*;
5 import java.io.*;
6 import java.util.*;
7
8
9
10 public class JSScope extends JS {
11
12 private JSScope parentScope;
13
14 private static final Object NULL_PLACEHOLDER = new Object();
15
16 public JSScope(JSScope parentScope) { this.parentScope = parentScope; }
17 public void declare(String s) throws JSExn { super.put(s, NULL_PLACEHOLDER); }
18 public JSScope getParentScope() { return parentScope; }
19
20 public Object get(Object key) throws JSExn {
21 Object o = super.get(key);
22 if (o != null) return o == NULL_PLACEHOLDER ? null : o;
23 else return parentScope == null ? null : parentScope.get(key);
24 }
25
26 public boolean has(Object key) throws JSExn { return super.get(key) != null; }
27 public void put(Object key, Object val) throws JSExn {
28 if (parentScope != null && !has(key)) parentScope.put(key, val);
29 else super.put(key, val == null ? NULL_PLACEHOLDER : val);
30 }
31
32 public JSScope top() {
33 JSScope s = this;
34 while(s.parentScope != null) s = s.parentScope;
35 return s;
36 }
37
38 public static class Global extends JSScope {
39 private final static Double NaN = new Double(Double.NaN);
40 private final static Double POSITIVE_INFINITY = new Double(Double.POSITIVE_INFINITY);
41
42 public Global() { super(null); }
43 public Object get(Object key) throws JSExn {
44
45 case "NaN": return NaN;
46 case "Infinity": return POSITIVE_INFINITY;
47 case "undefined": return null;
48 case "stringFromCharCode": return METHOD;
49 case "parseInt": return METHOD;
50 case "isNaN": return METHOD;
51 case "isFinite": return METHOD;
52 case "decodeURI": return METHOD;
53 case "decodeURIComponent": return METHOD;
54 case "encodeURI": return METHOD;
55 case "encodeURIComponent": return METHOD;
56 case "escape": return METHOD;
57 case "unescape": return METHOD;
58 case "parseInt": return METHOD;
59 //#end
60 return super.get(key);
61 }
62
63 public Object callMethod(Object method, Object a0, Object a1, Object a2, Object[] rest, int nargs) throws JSExn {
64 switch(nargs) {
65 case 0: {
66 //#switch(method)
67 case "stringFromCharCode":
68 char buf[] = new char[nargs];
69 for(int i=0; i<nargs; i++) buf[i] = (char)(JS.toInt(i==0?a0:i==1?a1:i==2?a2:rest[i-3]) & 0xffff);
70 return new String(buf);
71 //#end
72 break;
73 }
74 case 1: {
75 //#switch(method)
76 case "parseInt": return parseInt(a0, N(0));
77 case "isNaN": { double d = toDouble(a0); return d == d ? F : T; }
78 case "isFinite": { double d = toDouble(a0); return (d == d && !Double.isInfinite(d)) ? T : F; }
79 case "decodeURI": throw new JSExn("unimplemented");
80 case "decodeURIComponent": throw new JSExn("unimplemented");
81 case "encodeURI": throw new JSExn("unimplemented");
82 case "encodeURIComponent": throw new JSExn("unimplemented");
83 case "escape": throw new JSExn("unimplemented");
84 case "unescape": throw new JSExn("unimplemented");
85 //#end
86 break;
87 }
88 case 2: {
89 //#switch(method)
90 case "parseInt": return parseInt(a0, a1);
91 //#end
92 break;
93 }
94 }
95 return super.callMethod(method, a0, a1, a2, rest, nargs);
96 }
97
98 private Object parseInt(Object arg, Object r) {
99 int radix = JS.toInt(r);
100 String s = (String)arg;
101 int start = 0;
102 int length = s.length();
103 int sign = 1;
104 long n = 0;
105 if(radix != 0 && (radix < 2 || radix > 36)) return NaN;
106 while(start < length && Character.isWhitespace(s.charAt(start))) start++;
107 if((length >= start+1) && (s.charAt(start) == '+' || s.charAt(start) == '-')) {
108 sign = s.charAt(start) == '+' ? 1 : -1;
109 start++;
110 }
111 if(radix == 0 && length >= start+1 && s.charAt(start) == '0') {
112 start++;
113 if(length >= start+1 && (s.charAt(start) == 'x' || s.charAt(start) == 'X')) {
114 start++;
115 radix = 16;
116 } else {
117 radix = 8;
118 if(length == start || Character.digit(s.charAt(start+1),8)==-1) return JS.ZERO;
119 }
120 }
121 if(radix == 0) radix = 10;
122 if(length == start || Character.digit(s.charAt(start),radix) == -1) return NaN;
123 // try the fast way first
124 try {
125 String s2 = start == 0 ? s : s.substring(start);
126 return JS.N(sign*Integer.parseInt(s2,radix));
127 } catch(NumberFormatException e) { }
128 // fall through to a slower but emca-compliant method
129 for(int i=start;i<length;i++) {
130 int digit = Character.digit(s.charAt(i),radix);
131 if(digit < 0) break;
132 n = n*radix + digit;
133 if(n < 0) return NaN; // overflow;
134 }
135 if(n <= Integer.MAX_VALUE) return JS.N(sign*(int)n);
136 return JS.N((long)sign*n);
137 }
138
139 private Object parseFloat(Object arg) {
140 String s = (String)arg;
141 int start = 0;
142 int length = s.length();
143 while(start < length && Character.isWhitespace(s.charAt(0))) start++;
144 int end = length;
145 // as long as the string has no trailing garbage,this is fast, its slow with
146 // trailing garbage
147 while(start < end) {
148 try {
149 return JS.N(s.substring(start,length));
150 } catch(NumberFormatException e) { }
151 end--;
152 }
153 return NaN;
154 }
155 }
156 }
157
158