1 // Copyright 2004 Adam Megacz, see the COPYING file for licensing [GPL]
4 import org.ibex.util.*;
8 /** The minimum set of functionality required for objects which are manipulated by JavaScript */
9 public abstract class JS {
11 public static boolean checkAssertions = false;
13 public static final JS METHOD = new JS() { };
14 public final JS unclone() { return _unclone(); }
15 public final JS jsclone() throws JSExn { return new Clone(this); }
17 // FEATURE: JSEnumeration
18 public Enumeration keys() throws JSExn { throw new JSExn("you can't enumerate the keys of this object (class=" + getClass().getName() +")"); }
19 public JS get(JS key) throws JSExn { return null; }
20 public void put(JS key, JS val) throws JSExn { throw new JSExn("" + key + " is read only (class=" + getClass().getName() +")"); }
22 public InputStream getInputStream() throws IOException {
23 throw new IOException("this object doesn't have a stream associated with it " + getClass().getName() + ")");
26 public final boolean hasTrap(JS key) { return getTrap(key) != null; }
28 public JS callMethod(JS method, JS a0, JS a1, JS a2, JS[] rest, int nargs) throws JSExn {
29 throw new JSExn("method not found (" + JS.debugToString(method) + ")");
32 // FIXME: JSArgs objects, pointers into stack frame
33 public JS call(JS a0, JS a1, JS a2, JS[] rest, int nargs) throws JSExn {
34 throw new JSExn("you cannot call this object (class=" + this.getClass().getName() +")");
37 public final boolean equals(Object o) { return this == o || ((o instanceof JS) && jsequals((JS)o)); }
39 // FIXME: Remove this, eventually
40 public final String toString() { throw new Error("you shouldn't use toString() on JS objects"); }
42 // These are only used internally by org.ibex.js
43 Trap getTrap(JS key) { return null; }
44 void putTrap(JS key, Trap value) throws JSExn { throw new JSExn("traps cannot be placed on this object (class=" + this.getClass().getName() +")"); }
45 String coerceToString() throws JSExn { throw new JSExn("can't coerce to a string (class=" + getClass().getName() +")"); }
46 boolean jsequals(JS o) { return this == o; }
48 public static class O extends JS {
51 public Enumeration keys() throws JSExn { return entries == null ? emptyEnumeration : entries.keys(); }
52 public JS get(JS key) throws JSExn { return entries == null ? null : (JS)entries.get(key, null); }
53 public void put(JS key, JS val) throws JSExn { (entries==null?entries=new Hash():entries).put(key,null,val); }
55 /** retrieve a trap from the entries hash */
56 final Trap getTrap(JS key) {
57 return entries == null ? null : (Trap)entries.get(key, Trap.class);
60 /** retrieve a trap from the entries hash */
61 final void putTrap(JS key, Trap value) {
62 if (entries == null) entries = new Hash();
63 entries.put(key, Trap.class, value);
67 public static class BT extends O {
68 private BalancedTree bt;
69 private final BalancedTree bt() { if(bt != null) return bt; return bt = new BalancedTree(); }
70 public final void insertNode(int index, Object o) { bt().insertNode(index,o); }
71 public final void clear() { bt().clear(); }
72 public final Object getNode(int i) { return bt().getNode(i); }
73 public final int treeSize() { return bt().treeSize(); }
74 public final Object deleteNode(int i) { return bt().deleteNode(i); }
75 public final void replaceNode(int index, Object o) { bt().replaceNode(index,o); }
76 public final int indexNode(Object o) { return bt().indexNode(o); }
79 // FEATURE: JS.StringKeys
80 /* public static StringKeys extends JS {
81 public JS get(JS key) { return JS.isString(key) ? get(JS.toString(key) : null; }
85 JS _unclone() { return this; }
87 public interface Cloneable { }
89 public static class Clone extends JS.O implements Cloneable {
90 protected final JS clonee;
91 JS _unclone() { return clonee.unclone(); }
92 public JS getClonee() { return clonee; }
93 public Clone(JS clonee) throws JSExn {
94 if(!(clonee instanceof Cloneable)) throw new JSExn("" + clonee.getClass().getName() + " isn't cloneable");
97 public boolean jsequals(JS o) { return unclone().jsequals(o.unclone()); }
98 public Enumeration keys() throws JSExn { return clonee.keys(); }
99 public JS get(JS key) throws JSExn { return clonee.get(key); }
100 public void put(JS key, JS val) throws JSExn { clonee.put(key, val); }
101 public JS callMethod(JS method, JS a0, JS a1, JS a2, JS[] rest, int nargs) throws JSExn {
102 return clonee.callMethod(method, a0, a1, a2, rest, nargs);
104 public JS call(JS a0, JS a1, JS a2, JS[] rest, int nargs) throws JSExn {
105 return clonee.call(a0, a1, a2, rest, nargs);
107 public InputStream getInputStream() throws IOException { return clonee.getInputStream(); }
110 // Static Interpreter Control Methods ///////////////////////////////////////////////////////////////
112 /** log a message with the current JavaScript sourceName/line */
113 public static void log(Object message) { info(message); }
114 public static void debug(Object message) { Log.debug(Interpreter.getSourceName() + ":" + Interpreter.getLine(), message); }
115 public static void info(Object message) { Log.info(Interpreter.getSourceName() + ":" + Interpreter.getLine(), message); }
116 public static void warn(Object message) { Log.warn(Interpreter.getSourceName() + ":" + Interpreter.getLine(), message); }
117 public static void error(Object message) { Log.error(Interpreter.getSourceName() + ":" + Interpreter.getLine(), message); }
119 public static class NotPauseableException extends Exception { NotPauseableException() { } }
121 /** returns a callback which will restart the context; expects a value to be pushed onto the stack when unpaused */
122 public static UnpauseCallback pause() throws NotPauseableException {
123 Interpreter i = Interpreter.current();
124 if (i.pausecount == -1) throw new NotPauseableException();
126 switch(i.f.op[i.pc]) {
127 case Tokens.RETURN: case ByteCodes.PUT: get = false; break;
128 case ByteCodes.GET: get = true; break;
129 default: throw new Error("should never happen");
132 return new JS.UnpauseCallback(i,get);
135 public static class UnpauseCallback implements Task {
136 private Interpreter i;
138 UnpauseCallback(Interpreter i, boolean get) { this.i = i; this.get = get; }
139 public void perform() throws JSExn { unpause(); }
140 public JS unpause() throws JSExn { return unpause((JS)null); }
141 public JS unpause(JS o) throws JSExn {
142 if (o == JS.METHOD) throw new JSExn("can't return a method to a paused context");
143 if(get) i.stack.push(o);
146 public JS unpause(JSExn e) throws JSExn {
154 // Static Helper Methods ///////////////////////////////////////////////////////////////////////////////////
156 /** coerce an object to a Boolean */
157 public static boolean toBoolean(JS o) {
158 if(o == null) return false;
159 if(o instanceof JSNumber) return ((JSNumber)o).toBoolean();
160 if(o instanceof JSString) return ((JSString)o).length() != 0;
163 //#repeat long/int/double/float toLong/toInt/toDouble/toFloat Long/Integer/Double/Float parseLong/parseInt/parseDouble/parseFloat
164 /** coerce an object to a Number */
165 public static long toLong(JS o) throws JSExn {
166 if(o == null) return 0;
167 if(o instanceof JSNumber) return ((JSNumber)o).toLong();
168 if(o instanceof JSString) return Long.parseLong(o.coerceToString());
169 throw new JSExn("can't coerce a " + o.getClass().getName() + " to a number");
173 public static String toString(JS o) throws JSExn {
174 if(o == null) return "null";
175 return o.coerceToString();
178 public static String debugToString(JS o) {
179 try { return toString(o); }
180 catch(JSExn e) { return "[class=" + o.getClass().getName() + "]"; }
183 public static boolean isInt(JS o) {
184 if(o == null) return true;
185 if(o instanceof JSNumber.I) return true;
186 if(o instanceof JSNumber.B) return false;
187 if(o instanceof JSNumber) {
188 JSNumber n = (JSNumber) o;
189 return n.toInt() == n.toDouble();
191 if(o instanceof JSString) {
192 String s = ((JSString)o).s;
193 for(int i=0;i<s.length();i++)
194 if(s.charAt(i) < '0' || s.charAt(i) > '9') return false;
200 public static boolean isString(JS o) {
201 if(o instanceof JSString) return true;
205 // Instance Methods ////////////////////////////////////////////////////////////////////
207 public final static JS NaN = new JSNumber.D(Double.NaN);
208 public final static JS ZERO = new JSNumber.I(0);
209 public final static JS ONE = new JSNumber.I(1);
211 public static final JS T = new JSNumber.B(true);
212 public static final JS F = new JSNumber.B(false);
214 public static final JS B(boolean b) { return b ? T : F; }
215 public static final JS B(int i) { return i==0 ? F : T; }
217 private static final int CACHE_SIZE = 65536 / 4; // must be a power of two
218 private static final JSString[] stringCache = new JSString[CACHE_SIZE];
219 public static final JS S(String s) {
220 if(s == null) return null;
221 int slot = s.hashCode()&(CACHE_SIZE-1);
222 JSString ret = stringCache[slot];
223 if(ret == null || !ret.s.equals(s)) stringCache[slot] = ret = new JSString(s);
227 public static final JS N(double d) { return new JSNumber.D(d); }
228 public static final JS N(long l) { return new JSNumber.L(l); }
230 public static final JS N(Number n) {
231 if(n instanceof Integer) return N(n.intValue());
232 if(n instanceof Long) return N(n.longValue());
233 return N(n.doubleValue());
236 private static final JSNumber.I[] smallIntCache = new JSNumber.I[CACHE_SIZE];
237 private static final JSNumber.I[] largeIntCache = new JSNumber.I[CACHE_SIZE];
238 public static final JS N(int i) {
239 JSNumber.I ret = null;
240 int idx = i + smallIntCache.length / 2;
241 if (idx < CACHE_SIZE && idx > 0) {
242 ret = smallIntCache[idx];
243 if (ret != null) return ret;
245 else ret = largeIntCache[Math.abs(idx % CACHE_SIZE)];
246 if (ret == null || ret.i != i) {
247 ret = new JSNumber.I(i);
248 if (idx < smallIntCache.length && idx > 0) smallIntCache[idx] = ret;
249 else largeIntCache[Math.abs(idx % CACHE_SIZE)] = ret;
254 private static Enumeration emptyEnumeration = new Enumeration() {
255 public boolean hasMoreElements() { return false; }
256 public Object nextElement() { throw new NoSuchElementException(); }
259 public static JS fromReader(String sourceName, int firstLine, Reader sourceCode) throws IOException {
260 return JSFunction._fromReader(sourceName, firstLine, sourceCode);
263 // HACK: caller can't know if the argument is a JSFunction or not...
264 public static JS cloneWithNewParentScope(JS j, JSScope s) {
265 return ((JSFunction)j)._cloneWithNewParentScope(s);
269 // Trap support //////////////////////////////////////////////////////////////////////////////
271 /** performs a put, triggering traps if present; traps are run in an unpauseable interpreter */
272 public void putAndTriggerTraps(JS key, JS value) throws JSExn {
273 Trap t = getTrap(key);
274 if (t != null) t.invoke(value);
275 else put(key, value);
278 /** performs a get, triggering traps if present; traps are run in an unpauseable interpreter */
279 public JS getAndTriggerTraps(JS key) throws JSExn {
280 Trap t = getTrap(key);
281 if (t != null) return t.invoke();
282 else return get(key);
285 /** adds a trap, avoiding duplicates */
286 final void addTrap(JS key, JSFunction f) throws JSExn {
287 if (f.numFormalArgs > 1) throw new JSExn("traps must take either one argument (write) or no arguments (read)");
288 boolean isRead = f.numFormalArgs == 0;
289 for(Trap t = getTrap(key); t != null; t = t.next) if (t.f == f) return;
290 putTrap(key, new Trap(this, key, f, (Trap)getTrap(key)));
293 /** deletes a trap, if present */
294 final void delTrap(JS key, JSFunction f) throws JSExn {
295 Trap t = (Trap)getTrap(key);
296 if (t == null) return;
297 if (t.f == f) { putTrap(t.name, t.next); return; }
298 for(; t.next != null; t = t.next) if (t.next.f == f) { t.next = t.next.next; return; }