Java ScriptRuntime.UNDEFINED属性代码示例

/**
 * ECMA 15.4.4.5 Array.prototype.join (separator)
 *
 * @param self      self reference
 * @param separator element separator
 * @return string representation after join
 */
@Function(attributes = Attribute.NOT_ENUMERABLE)
public static String join(final Object self, final Object separator) {
    final StringBuilder    sb   = new StringBuilder();
    final Iterator<Object> iter = arrayLikeIterator(self, true);
    final String           sep  = separator == ScriptRuntime.UNDEFINED ? "," : JSType.toString(separator);

    while (iter.hasNext()) {
        final Object obj = iter.next();

        if (obj != null && obj != ScriptRuntime.UNDEFINED) {
            sb.append(JSType.toString(obj));
        }

        if (iter.hasNext()) {
            sb.append(sep);
        }
    }

    return sb.toString();
}
 

@Override
public Object fastPopObject() {
    if (length() == 0) {
        return ScriptRuntime.UNDEFINED;
    }
    final int newLength = (int)decreaseLength();
    final Object elem = array[newLength];
    array[newLength] = ScriptRuntime.EMPTY;
    return elem;
}
 

/**
 * Returns if the given object is a "callable"
 * @param obj object to be checked for callability
 * @return true if the obj is callable
 */
public static boolean isCallable(final Object obj) {
    if (obj == ScriptRuntime.UNDEFINED || obj == null) {
        return false;
    }

    return obj instanceof ScriptFunction ||
        isJSObjectFunction(obj) ||
        BeansLinker.isDynamicMethod(obj) ||
        obj instanceof BoundCallable ||
        isFunctionalInterfaceObject(obj) ||
        obj instanceof StaticClass;
}
 

/**
 * ECMA 15.4.4.6 Array.prototype.pop ()
 *
 * @param self self reference
 * @return array after pop
 */
@Function(attributes = Attribute.NOT_ENUMERABLE)
public static Object pop(final Object self) {
    try {
        final ScriptObject sobj = (ScriptObject)self;

        if (bulkable(sobj)) {
            return sobj.getArray().pop();
        }

        final long len = JSType.toUint32(sobj.getLength());

        if (len == 0) {
            sobj.set("length", 0, CALLSITE_STRICT);
            return ScriptRuntime.UNDEFINED;
        }

        final long   index   = len - 1;
        final Object element = sobj.get(index);

        sobj.delete(index, true);
        sobj.set("length", index, CALLSITE_STRICT);

        return element;
    } catch (final ClassCastException | NullPointerException e) {
        throw typeError("not.an.object", ScriptRuntime.safeToString(self));
    }
}
 

@Override
public ArrayData set(final int index, final Object value, final boolean strict) {
    if (JSType.isRepresentableAsInt(value)) {
        return set(index, JSType.toInt32(value), strict);
    } else if (value == ScriptRuntime.UNDEFINED) {
        return new UndefinedArrayFilter(this).set(index, value, strict);
    }

    final ArrayData newData = convert(value == null ? Object.class : value.getClass());
    return newData.set(index, value, strict);
}
 

@Override
public Object pop() {
    final int index = (int)length() - 1;
    if (super.has(index)) {
        final boolean isDeleted = isDeleted(index);
        final Object value      = super.pop();

        lo = Math.min(index + 1, lo);
        hi = Math.min(index, hi);
        return isDeleted ? ScriptRuntime.UNDEFINED : value;
    }

    return super.pop();
}
 

private static ScriptFunction compareFunction(final Object comparefn) {
    if (comparefn == ScriptRuntime.UNDEFINED) {
        return null;
    }

    if (! (comparefn instanceof ScriptFunction)) {
        throw typeError("not.a.function", ScriptRuntime.safeToString(comparefn));
    }

    return (ScriptFunction)comparefn;
}
 

private static Object[] sort(final Object[] array, final Object comparefn) {
    final ScriptFunction cmp = compareFunction(comparefn);

    final List<Object> list = Arrays.asList(array);
    final Object cmpThis = cmp == null || cmp.isStrict() ? ScriptRuntime.UNDEFINED : Global.instance();

    Collections.sort(list, new Comparator<Object>() {
        private final MethodHandle call_cmp = getCALL_CMP();
        @Override
        public int compare(final Object x, final Object y) {
            if (x == ScriptRuntime.UNDEFINED && y == ScriptRuntime.UNDEFINED) {
                return 0;
            } else if (x == ScriptRuntime.UNDEFINED) {
                return 1;
            } else if (y == ScriptRuntime.UNDEFINED) {
                return -1;
            }

            if (cmp != null) {
                try {
                    return (int)Math.signum((double)call_cmp.invokeExact(cmp, cmpThis, x, y));
                } catch (final RuntimeException | Error e) {
                    throw e;
                } catch (final Throwable t) {
                    throw new RuntimeException(t);
                }
            }

            return JSType.toString(x).compareTo(JSType.toString(y));
        }
    });

    return list.toArray(new Object[array.length]);
}
 

private static Type getPropertyType(final ScriptObject sobj, final String name) {
    final FindProperty find = sobj.findProperty(name, true);
    if (find == null) {
        return null;
    }

    final Property property      = find.getProperty();
    final Class<?> propertyClass = property.getType();
    if (propertyClass == null) {
        // propertyClass == null means its value is Undefined. It is probably not initialized yet, so we won't make
        // a type assumption yet.
        return null;
    } else if (propertyClass.isPrimitive()) {
        return Type.typeFor(propertyClass);
    }

    final ScriptObject owner = find.getOwner();
    if (property.hasGetterFunction(owner)) {
        // Can have side effects, so we can't safely evaluate it; since !propertyClass.isPrimitive(), it's Object.
        return Type.OBJECT;
    }

    // Safely evaluate the property, and return the narrowest type for the actual value (e.g. Type.INT for a boxed
    // integer).
    final Object value = property.needsDeclaration() ? ScriptRuntime.UNDEFINED : property.getObjectValue(owner, owner);
    if (value == ScriptRuntime.UNDEFINED) {
        return null;
    }
    return Type.typeFor(JSType.unboxedFieldType(value));
}
 

private static Object reduceInner(final ArrayLikeIterator<Object> iter, final Object self, final Object... args) {
    final Object  callbackfn          = args.length > 0 ? args[0] : ScriptRuntime.UNDEFINED;
    final boolean initialValuePresent = args.length > 1;

    Object initialValue = initialValuePresent ? args[1] : ScriptRuntime.UNDEFINED;

    if (callbackfn == ScriptRuntime.UNDEFINED) {
        throw typeError("not.a.function", "undefined");
    }

    if (!initialValuePresent) {
        if (iter.hasNext()) {
            initialValue = iter.next();
        } else {
            throw typeError("array.reduce.invalid.init");
        }
    }

    //if initial value is ScriptRuntime.UNDEFINED - step forward once.
    return new IteratorAction<Object>(Global.toObject(self), callbackfn, ScriptRuntime.UNDEFINED, initialValue, iter) {
        private final MethodHandle reduceInvoker = getREDUCE_CALLBACK_INVOKER();

        @Override
        protected boolean forEach(final Object val, final long i) throws Throwable {
            // TODO: why can't I declare the second arg as Undefined.class?
            result = reduceInvoker.invokeExact(callbackfn, ScriptRuntime.UNDEFINED, result, val, i, self);
            return true;
        }
    }.apply();
}
 

@Override
public Object[] asObjectArray() {
    final Object[] value = super.asObjectArray();

    if (lo < Integer.MAX_VALUE) {
        final int end = (int)Math.min(hi + 1, Integer.MAX_VALUE);
        for (int i = (int)lo; i < end; i++) {
            value[i] = ScriptRuntime.UNDEFINED;
        }
    }

    return value;
}
 

private Object get(final long index) {
    final Object obj = extraElements.get(index);
    if (obj == null) {
        return ScriptRuntime.UNDEFINED;
    }
    return obj;
}
 

/**
 * Return the ArrayData for this ScriptObject
 * @param self self
 * @param obj script object to check
 * @return ArrayData, ArrayDatas have toString methods, return Undefined if data missing
 */
@Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR)
public static Object getArrayData(final Object self, final Object obj) {
    try {
        return ((ScriptObject)obj).getArray();
    } catch (final ClassCastException e) {
        return ScriptRuntime.UNDEFINED;
    }
}
 

static Object translateUndefined(final Object obj) {
    return (obj == ScriptRuntime.UNDEFINED)? null : obj;
}
 

@Override
public Object pop() {
    return ScriptRuntime.UNDEFINED;
}