- 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"); }
-
-
- // 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 boolean sealed = false;
- public Obj() { this(false); }
- public Obj(boolean sealed) { this.sealed = sealed; }
- 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()); }
+ // 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 Number N(int i) { return new Integer(i); }
+ public static final Number N(long l) { return new Long(l); }
+ public static final Number N(double d) { return new Double(d); }
+ public static final Number N(String s) { return new Double(s); }
+ 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; }
+
+ private static Enumeration emptyEnumeration = new Enumeration() {
+ public boolean hasMoreElements() { return false; }
+ public Object nextElement() { throw new NoSuchElementException(); }
+ };
+
+ private Hash entries = null;
+ public Enumeration keys() { return entries == null ? emptyEnumeration : entries.keys(); }
+ public Object get(Object key) { return entries == null ? null : entries.get(key, null); }
+ public void put(Object key, Object val) { if (entries == null) entries = new Hash(); entries.put(key, null, val); }
+
+
+ // Trap support //////////////////////////////////////////////////////////////////////////////
+
+ /** override and return true to allow placing traps on this object */
+ protected boolean isTrappable() { return false; }
+
+ /** performs a put, triggering traps if present; traps are run in an unpauseable interpreter */
+ public final void putAndTriggerTraps(Object key, Object value) {
+ Trap t = getTrap(key);
+ if (t != null) t.invoke(key, value);
+ else put(key, value);