public static boolean toBoolean(Object o) {
if (o == null) return false;
if (o instanceof Boolean) return ((Boolean)o).booleanValue();
- if (o instanceof Number) return o.equals(new Integer(0));
+ if (o instanceof Long) return ((Long)o).longValue() != 0;
+ if (o instanceof Integer) return ((Integer)o).intValue() != 0;
+ if (o instanceof Number) {
+ double d = ((Number) o).doubleValue();
+ // NOTE: d == d is a test for NaN. It should be faster than Double.isNaN()
+ return d != 0.0 && d == d;
+ }
+ if (o instanceof String) return ((String)o).length() != 0;
return true;
}
/** coerce an object to a Long */
public static long toLong(Object o) { return toNumber(o).longValue(); }
+ /** coerce an object to an Int */
+ public static int toInt(Object o) { return toNumber(o).intValue(); }
+
/** coerce an object to a Double */
public static double toDouble(Object o) { return toNumber(o).doubleValue(); }
public static Number toNumber(Object o) {
if (o == null) return new Long(0);
if (o instanceof Number) return ((Number)o);
- if (o instanceof String) try { return new Double((String)o); } catch (NumberFormatException e) { return new Double(0); }
+
+ // 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);
if (o instanceof JS) return ((JS)o).coerceToNumber();
- throw new Error("a " + o.getClass().getName() + " has no numeric value");
+ throw new Error("toNumber() got object of type " + o.getClass().getName() + " which we don't know how to handle");
}
-
-
+
+ /** coerce an object to a String */
+ public static String toString(Object o) {
+ if(o == null) return "null";
+ if(o instanceof String) return (String) o;
+ if(o instanceof Integer || o instanceof Long || o instanceof Boolean) return o.toString();
+ if(o instanceof JS) return ((JS)o).coerceToString();
+ if(o instanceof Double || o instanceof Float) {
+ double d = ((Number)o).doubleValue();
+ if((int)d == d) return Integer.toString((int)d);
+ return o.toString();
+ }
+ return o.toString();
+ }
+
// Instance Methods ////////////////////////////////////////////////////////////////////
public abstract Object get(Object key) throws JS.Exn;
public abstract void put(Object key, Object val) throws JS.Exn;
public abstract Object[] keys();
-
- public Number coerceToNumber() { throw new Error("you cannot coerce a " + this.getClass().getName() + " into a Number"); }
- public String coerceToString() { throw new Error("you cannot coerce a " + this.getClass().getName() + " into a String"); }
- public boolean coerceToBoolean() { throw new Error("you cannot coerce a " + this.getClass().getName() + " into a Boolean"); }
+ public Object callMethod(Object method, Array args, boolean checkOnly) throws JS.Exn {
+ if(checkOnly) return Boolean.FALSE;
+ Object o = get(method);
+ if(o instanceof JS.Callable) {
+ return ((JS.Callable)o).call(args);
+ } else if(o == null) {
+ throw new JS.Exn("Attempted to call non-existent method: " + method);
+ } else {
+ throw new JS.Exn("Attempted to call a non-method: " +method);
+ }
+ }
+
+ public Number coerceToNumber() { return new Integer(0); }
+ public String coerceToString() { throw new JS.Exn("tried to coerce a JavaScript object to a String"); }
+ public boolean coerceToBoolean() { return true; }
+
+ public String typeName() { return "object"; }
// Inner Classes /////////////////////////////////////////////////////////////////////////
/** A sensible implementation of the abstract methods in the JS class */
public static class Obj extends JS {
- private Hash entries = new Hash();
+ private Hash entries = null;
private boolean sealed = false;
public Obj() { this(false); }
public Obj(boolean sealed) { this.sealed = sealed; }
- /** a sealed object cannot have its properties modified */
- public void setSeal(boolean sealed) { this.sealed = sealed; }
- public Object get(Object key) { return entries.get(key); }
- public void put(Object key, Object val) { if (!sealed) entries.put(key, val); }
- public Object[] keys() { return(entries.keys()); }
+ public void setSeal(boolean sealed) { this.sealed = sealed; } ///< a sealed object cannot have its properties modified
+ public void put(Object key, Object val) { put(key, null, val); }
+ protected void put(Object key, Object key2, Object val) {
+ if (sealed) return;
+ if (entries == null) entries = new Hash();
+ entries.put(key, key2, val); }
+ public Object[] keys() { return entries == null ? new Object[0] : entries.keys(); }
+ public Object get(Object key) { return get(key, null); }
+ protected Object get(Object key, Object key2) {
+ if (entries == null) return null;
+ if(key2 == null && callMethod((String)key, null, true) == Boolean.TRUE)
+ return new Internal.CallableStub(this, key);
+ return entries.get(key, key2);
+ }
}
/** An exception which can be thrown and caught by JavaScript code */
public void declare(String s) { super.declare(s); }
}
+ /** the result of a graft */
+ public static class Graft extends JS {
+ private JS graftee;
+ private Object replaced_key;
+ private Object replaced_val;
+ public Graft(JS graftee, Object key, Object val) {
+ if (graftee instanceof Array) throw new JS.Exn("can't graft onto Arrays (yet)");
+ if (graftee instanceof Callable) throw new JS.Exn("can't graft onto Callables (yet)");
+ if (graftee instanceof Scope) throw new JS.Exn("can't graft onto Scopes (yet)");
+ this.graftee = 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 callMethod(Object method, Array args, boolean checkOnly) throws JS.Exn {
+ if (!replaced_key.equals(method)) return graftee.callMethod(method, args, checkOnly);
+ if (replaced_val instanceof Callable) return checkOnly ? Boolean.TRUE : ((Callable)replaced_val).call(args);
+ if (checkOnly) return Boolean.FALSE;
+ throw new JS.Exn("attempt to call non-function");
+ }
+ 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 Object[] keys() {
+ Object[] ret = graftee.keys();
+ for(int i=0; i<ret.length; i++) if (replaced_key.equals(ret[i])) return ret;
+ Object[] ret2 = new Object[ret.length + 1];
+ System.arraycopy(ret, 0, ret2, 0, ret.length);
+ ret2[ret2.length - 1] = replaced_key;
+ return ret2;
+ }
+ }
+
/** anything that is callable with the () operator */
public static abstract class Callable extends JS.Obj {
public abstract Object call(JS.Array args) throws JS.Exn;
/** a Callable which was compiled from JavaScript code */
public static class CompiledFunction extends CompiledFunctionImpl {
+ public int getNumFormalArgs() { return numFormalArgs; }
CompiledFunction(String sourceName, int firstLine, Reader sourceCode, Scope scope) throws IOException {
super(sourceName, firstLine, sourceCode, scope);
}
}
+
+ /** a scope that is populated with js objects and functions normally found in the global scope */
+ public static class GlobalScope extends GlobalScopeImpl {
+ public GlobalScope() { this(null); }
+ public GlobalScope(JS.Scope parent) { super(parent); }
+ }
public static final JS Math = new org.xwt.js.Math();
CompiledFunction currentCompiledFunction = null;
Vec stack = new Vec();
- int line = -1;
+ public Scope scope = null;
+ int pc = 0;
+ boolean paused = false;
+
+ CompiledFunction tailCallFunction = null;
+ JS.Array tailCallArgs = null;
+
+ public Thread(CompiledFunction function) {
+ this(function, new CompiledFunctionImpl.FunctionScope("unknown", function.parentScope));
+ }
+ public Thread(CompiledFunction function, Scope scope) {
+ stack.push(new CompiledFunctionImpl.CallMarker(this));
+ stack.push(new JS.Array());
+ this.currentCompiledFunction = function;
+ this.scope = scope;
+ }
- /** binds this thread to the current Java Thread */
- public void bindToCurrentJavaThread() { javaThreadToJSThread.put(java.lang.Thread.currentThread(), this); }
+ public void setTailCall(JS.CompiledFunction f, JS.Array args) { tailCallFunction = f; tailCallArgs = args; }
- /** returns the line of code that is currently executing */
- public int getLine() { return line; }
+ public static JS.Thread current() { return (JS.Thread)javaThreadToJSThread.get(java.lang.Thread.currentThread()); }
- /** returns the name of the source code file which declared the currently executing function */
+ public Object resume() { bind(); paused = false; Object ret = CompiledFunctionImpl.eval(this); unbind(); return ret; }
+ public void pause() { paused = true; unbind(); }
+ public void bind() { javaThreadToJSThread.put(java.lang.Thread.currentThread(), this); }
+ public void unbind() { if (current() == this) javaThreadToJSThread.remove(java.lang.Thread.currentThread()); }
+ public int getLine() { return currentCompiledFunction == null ? -1 : currentCompiledFunction.getLine(this); }
public String getSourceName() { return currentCompiledFunction == null ? null : currentCompiledFunction.getSourceName(); }
/** fetches the currently-executing javascript function */
public JS.CompiledFunction getCurrentCompiledFunction() { return currentCompiledFunction; }
-
-
- // Statics ///////////////////////////////////////////////////////////////////////
-
private static Hashtable javaThreadToJSThread = new Hashtable();
-
- /** returns the JS thread for a given Java thread, creating one if necessary */
- public static JS.Thread fromJavaThread(java.lang.Thread t) {
- JS.Thread ret = (JS.Thread)javaThreadToJSThread.get(t);
- if (ret == null) {
- ret = new JS.Thread();
- ret.bindToCurrentJavaThread();
- }
- return ret;
- }
-
}
}