X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=src%2Forg%2Fxwt%2Fjs%2FJS.java;h=0191a59b8e5af97f7caad74deeb02c8abe8df400;hb=62b09c2447b9516863916b076fe64fe98ec1670f;hp=f1f67264141745d87602655c0cddc3e70015e66e;hpb=a76646eb76b01b5f1b5f0507b1c4bcd4202f1f11;p=org.ibex.core.git

diff --git a/src/org/xwt/js/JS.java b/src/org/xwt/js/JS.java
index f1f6726..0191a59 100644
--- a/src/org/xwt/js/JS.java
+++ b/src/org/xwt/js/JS.java
@@ -1,25 +1,55 @@
 // Copyright 2003 Adam Megacz, see the COPYING file for licensing [GPL] 
-
 package org.xwt.js; 
+
 import org.xwt.util.*; 
 import org.xwt.*; 
 import java.io.*;
 import java.util.*;
 
-/**
- *  The public API for the JS engine.  JS itself is actually a class
- *  implementing the absolute minimal amount of functionality for an
- *  Object which can be manipulated by JavaScript code.
- */
-public abstract class JS { 
+/** The minimum set of functionality required for objects which are manipulated by JavaScript */
+public class JS extends org.xwt.util.BalancedTree { 
+
+    // Static Interpreter Control Methods ///////////////////////////////////////////////////////////////
 
-    // Public Helper Methods //////////////////////////////////////////////////////////////////////
+    /** log a message with the current JavaScript sourceName/line */
+    public static void log(Object o, Object message) { logJS(message); }
+    public static void log(Object message) { Log.echo(JS.getSourceName() + ":" + JS.getLine(), message); }
 
-    /** parse and compile a function */
-    public static JSFunction parse(String sourceName, int firstLine, Reader sourceCode) throws IOException {
-        return new JSFunction(sourceName, firstLine, sourceCode, null);
+    public static int getLine() {
+        Interpreter c = Interpreter.current();
+        return c == null || c.f == null || c.pc < 0 || c.pc >= c.f.size ? -1 : c.f.line[c.pc];
+    }
+
+    public static String getSourceName() {
+        Interpreter c = Interpreter.current();
+        return c == null || c.f == null ? null : c.f.sourceName;
+    } 
+
+    public static class NotPauseableException extends Exception { NotPauseableException() { } }
+
+    /** returns a callback which will restart the context; expects a value to be pushed onto the stack when unpaused */
+    public static UnpauseCallback pause() throws NotPauseableException {
+        Interpreter i = Interpreter.current();
+        if (i.pausecount == -1) throw new NotPauseableException();
+        i.pausecount++;
+        return new JS.UnpauseCallback(i);
+    }
+
+    public static class UnpauseCallback implements Scheduler.Task {
+        Interpreter i;
+        UnpauseCallback(Interpreter i) { this.i = i; }
+        public void perform() throws JSExn { unpause(null); }
+        public void unpause(Object o) throws JSExn {
+            // FIXME: if o instanceof JSExn, throw it into the JSworld
+            i.stack.push(o);
+            i.resume();
+        }
     }
 
+
+
+    // Static Helper Methods ///////////////////////////////////////////////////////////////////////////////////
+
     /** coerce an object to a Boolean */
     public static boolean toBoolean(Object o) {
         if (o == null) return false;
@@ -46,14 +76,14 @@ public abstract class JS {
 
     /** coerce an object to a Number */
     public static Number toNumber(Object o) {
-        if (o == null) return new Long(0);
+        if (o == null) return ZERO;
         if (o instanceof Number) return ((Number)o);
 
         // NOTE: There are about 3 pages of rules in ecma262 about string to number conversions
         //       We aren't even close to following all those rules.  We probably never will be.
         if (o instanceof String)
-            try { return new Double((String)o); } catch (NumberFormatException e) { return new Double(Double.NaN); }
-        if (o instanceof Boolean) return ((Boolean)o).booleanValue() ? new Long(1) : new Long(0);
+            try { return N((String)o); } catch (NumberFormatException e) { return N(Double.NaN); }
+        if (o instanceof Boolean) return ((Boolean)o).booleanValue() ? N(1) : ZERO;
         if (o instanceof JS) return ((JS)o).coerceToNumber();
         throw new Error("toNumber() got object of type " + o.getClass().getName() + " which we don't know how to handle");
     }
@@ -71,82 +101,124 @@ public abstract class JS {
         }
         return o.toString();
     }
+
     
     // Instance Methods ////////////////////////////////////////////////////////////////////
+
+    public static final Integer ZERO = new Integer(0);
  
-    public abstract Object get(Object key) throws JS.Exn; 
-    public void put(Object key, Object val) throws JS.Exn { throw new JS.Exn("you cannot put to this object"); }
+    // this gets around a wierd fluke in the Java type checking rules for ?..:
+    public static final Object T = Boolean.TRUE;
+    public static final Object F = Boolean.FALSE;
+
+    public static final Boolean B(boolean b) { return b ? Boolean.TRUE : Boolean.FALSE; }
+    public static final Boolean B(int i) { return i==0 ? Boolean.FALSE : Boolean.TRUE; }
+    public static final Number N(String s) { return s.indexOf('.') == -1 ? N(Integer.parseInt(s)) : new Double(s); }
+    public static final Number N(double d) { return (int)d == d ? N((int)d) : new Double(d); }
+    public static final Number N(long l) { return N((int)l); }
+
+    private static final Integer[] smallIntCache = new Integer[65535 / 4];
+    private static final Integer[] largeIntCache = new Integer[65535 / 4];
+    public static final Number N(int i) {
+        Integer ret = null;
+        int idx = i + smallIntCache.length / 2;
+        if (idx < smallIntCache.length && idx > 0) {
+            ret = smallIntCache[idx];
+            if (ret != null) return ret;
+        }
+        else ret = largeIntCache[Math.abs(idx % largeIntCache.length)];
+        if (ret == null || ret.intValue() != i) {
+            ret = new Integer(i);
+            if (idx < smallIntCache.length && idx > 0) smallIntCache[idx] = ret;
+            else largeIntCache[Math.abs(idx % largeIntCache.length)] = ret;
+        }
+        return ret;
+    }
+    
+    private static Enumeration emptyEnumeration = new Enumeration() {
+            public boolean hasMoreElements() { return false; }
+            public Object nextElement() { throw new NoSuchElementException(); }
+        };
+    
+    private Hash entries = null;
+    public Enumeration keys() throws JSExn {
+        return entries == null ? emptyEnumeration : entries.keys();
+    }
+    public Object get(Object key) throws JSExn { return entries == null ? null : entries.get(key, null); }
+    public void put(Object key, Object val) throws JSExn {
+        if (entries == null) entries = new Hash();
+        entries.put(key, null, val);
+    }
 
-    public Enumeration keys() { throw new Error("you cannot apply for..in to a " + this.getClass().getName()); }
 
-    public Number coerceToNumber() { throw new JS.Exn("tried to coerce a JavaScript object to a Number"); }
-    public String coerceToString() { throw new JS.Exn("tried to coerce a JavaScript object to a String"); }
-    public boolean coerceToBoolean() { throw new JS.Exn("tried to coerce a JavaScript object to a Boolean"); }
+    // Trap support //////////////////////////////////////////////////////////////////////////////
 
-    public String typeName() { return "object"; }
+    /** override and return true to allow placing traps on this object.
+	 *  if isRead true, this is a read trap, otherwise write trap
+	 **/
+    protected boolean isTrappable(Object name, boolean isRead) { return false; }
 
+    /** performs a put, triggering traps if present; traps are run in an unpauseable interpreter */
+    public void putAndTriggerTraps(Object key, Object value) throws JSExn {
+        Trap t = getTrap(key);
+        if (t != null) t.invoke(value);
+        else put(key, value);
+    }
 
-    // Inner Classes /////////////////////////////////////////////////////////////////////////
+    /** performs a get, triggering traps if present; traps are run in an unpauseable interpreter */
+    public Object getAndTriggerTraps(Object key) throws JSExn {
+        Trap t = getTrap(key);
+        if (t != null) return t.invoke();
+        else return get(key);
+    }
 
-    /** An exception which can be thrown and caught by JavaScript code */
-    public static class Exn extends RuntimeException { 
-        private Object js = null; 
-        public Exn(Object js) { this.js = js; } 
-        public String toString() { return "JS.Exn: " + js; }
-        public String getMessage() { return toString(); }
-        public Object getObject() { return js; } 
-    } 
+    /** retrieve a trap from the entries hash */
+    protected final Trap getTrap(Object key) {
+        return entries == null ? null : (Trap)entries.get(key, Trap.class);
+    }
 
-    /** the result of a graft */
-    public static class Graft extends JSCallable {
-        private JS graftee;
-        private Object replaced_key;
-        private Object replaced_val;
-        public Graft(Object graftee, Object key, Object val) {
-            if (graftee instanceof JSArray) throw new JS.Exn("can't graft onto JSArrays (yet)");
-            if (graftee instanceof JSCallable) throw new JS.Exn("can't graft onto JSCallables (yet)");
-            if (graftee instanceof JSScope) throw new JS.Exn("can't graft onto JSScopes (yet)");
-            this.graftee = (JS)graftee;
-            replaced_key = key;
-            replaced_val = val;
-        }
-        public boolean equals(Object o) { return (this == o || graftee.equals(o)); }
-        public int hashCode() { return graftee.hashCode(); }
-        public Object get(Object key) { return replaced_key.equals(key) ? replaced_val : graftee.get(key); }
-        public void put(Object key, Object val) { graftee.put(key, val); }
-        public Object call(Object method, JSArray args) {
-            if (replaced_key.equals(method)) return ((JSCallable)replaced_val).call(null, args);
-            else if (graftee instanceof JSCallable) return ((JSCallable)graftee).call(method, args);
-            else throw new JS.Exn("cannot call this value");
-        }
-        public Number coerceToNumber() { return graftee.coerceToNumber(); }
-        public String coerceToString() { return graftee.coerceToString(); }
-        public boolean coerceToBoolean() { return graftee.coerceToBoolean(); }
-        public String typeName() { return graftee.typeName(); }
-        public Enumeration keys() {
-            return new Enumeration() {
-                    Enumeration graftee_enumeration = graftee.keys();
-                    boolean returned_replaced = false;
-                    public boolean hasMoreElements() {
-                        if (graftee_enumeration.hasMoreElements()) return true;
-                        return !returned_replaced;
-                    }
-                    public Object nextElement() {
-                        if (!graftee_enumeration.hasMoreElements()) {
-                            if (returned_replaced) throw new NoSuchElementException();
-                            returned_replaced = true;
-                            return replaced_key;
-                        } else {
-                            Object ret = graftee_enumeration.nextElement();
-                            if (!returned_replaced && ret.equals(replaced_key)) returned_replaced = true;
-                            return ret;
-                        }
-                    }
-                };
-        }
+    /** retrieve a trap from the entries hash */
+    protected final void putTrap(Object key, Trap value) {
+        if (entries == null) entries = new Hash();
+        entries.put(key, Trap.class, value);
     }
-} 
 
+    /** adds a trap, avoiding duplicates */
+    protected final void addTrap(Object name, JSFunction f) throws JSExn {
+        if (f.numFormalArgs > 1) throw new JSExn("traps must take either one argument (write) or no arguments (read)");
+        boolean isRead = f.numFormalArgs == 0;
+        if (!isTrappable(name, isRead)) throw new JSExn("not allowed "+(isRead?"read":"write")+" trap on property: "+name);
+        for(Trap t = getTrap(name); t != null; t = t.next) if (t.f == f) return;
+        putTrap(name, new Trap(this, name.toString(), f, (Trap)getTrap(name)));
+    }
 
+    /** deletes a trap, if present */
+    protected final void delTrap(Object name, JSFunction f) {
+        Trap t = (Trap)getTrap(name);
+        if (t == null) return;
+        if (t.f == f) { putTrap(t.name, t.next); return; }
+        for(; t.next != null; t = t.next) if (t.next.f == f) { t.next = t.next.next; return; }
+    }
+
+
+    // Call Support //////////////////////////////////////////////////////////////////////////////
+
+    // return this from get() if the key was actually a method.
+    public static final Object METHOD = new Object();
+    public Object callMethod(Object method, Object a0, Object a1, Object a2, Object[] rest, int nargs) throws JSExn {
+        throw new JSExn("attempted to call the null value (method "+method+")");
+    }    
+    public Object call(Object a0, Object a1, Object a2, Object[] rest, int nargs) throws JSExn {
+        throw new JSExn("you cannot call this object (class=" + this.getClass().getName() +")");
+    }
 
 
+    // Typing Support //////////////////////////////////////////////////////////////////////////////
+
+    public Number coerceToNumber() { throw new JSRuntimeExn("tried to coerce a JavaScript object to a Number"); }
+    public String coerceToString() { throw new JSRuntimeExn("tried to coerce a JavaScript object to a String"); }
+    public boolean coerceToBoolean() { throw new JSRuntimeExn("tried to coerce a JavaScript object to a Boolean"); }
+
+    public String typeName() { return "object"; }
+
+}