/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Rhino code, released
* May 6, 1999.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1997-1999
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Norris Boyd
* Igor Bukanov
*
* Alternatively, the contents of this file may be used under the terms of
* the GNU General Public License Version 2 or later (the "GPL"), in which
* case the provisions of the GPL are applicable instead of those above. If
* you wish to allow use of your version of this file only under the terms of
* the GPL and not to allow others to use your version of this file under the
* MPL, indicate your decision by deleting the provisions above and replacing
* them with the notice and other provisions required by the GPL. If you do
* not delete the provisions above, a recipient may use your version of this
* file under either the MPL or the GPL.
*
* ***** END LICENSE BLOCK ***** */
package org.mozilla.javascript;
/**
* This class implements the "arguments" object.
*
* See ECMA 10.1.8
*
* @see org.mozilla.javascript.NativeCall
* @author Norris Boyd
*/
final class Arguments extends IdScriptableObject
{
static final long serialVersionUID = 4275508002492040609L;
public Arguments(NativeCall activation)
{
this.activation = activation;
Scriptable parent = activation.getParentScope();
setParentScope(parent);
setPrototype(ScriptableObject.getObjectPrototype(parent));
args = activation.originalArgs;
lengthObj = new Integer(args.length);
NativeFunction f = activation.function;
calleeObj = f;
int version = f.getLanguageVersion();
if (version <= Context.VERSION_1_3
&& version != Context.VERSION_DEFAULT)
{
callerObj = null;
} else {
callerObj = NOT_FOUND;
}
}
public String getClassName()
{
return "Object";
}
public boolean has(int index, Scriptable start)
{
if (0 <= index && index < args.length) {
if (args[index] != NOT_FOUND) {
return true;
}
}
return super.has(index, start);
}
public Object get(int index, Scriptable start)
{
if (0 <= index && index < args.length) {
Object value = args[index];
if (value != NOT_FOUND) {
if (sharedWithActivation(index)) {
NativeFunction f = activation.function;
String argName = f.getParamOrVarName(index);
value = activation.get(argName, activation);
if (value == NOT_FOUND) Kit.codeBug();
}
return value;
}
}
return super.get(index, start);
}
private boolean sharedWithActivation(int index)
{
NativeFunction f = activation.function;
int definedCount = f.getParamCount();
if (index < definedCount) {
// Check if argument is not hidden by later argument with the same
// name as hidden arguments are not shared with activation
if (index < definedCount - 1) {
String argName = f.getParamOrVarName(index);
for (int i = index + 1; i < definedCount; i++) {
if (argName.equals(f.getParamOrVarName(i))) {
return false;
}
}
}
return true;
}
return false;
}
public void put(int index, Scriptable start, Object value)
{
if (0 <= index && index < args.length) {
if (args[index] != NOT_FOUND) {
if (sharedWithActivation(index)) {
String argName;
argName = activation.function.getParamOrVarName(index);
activation.put(argName, activation, value);
return;
}
synchronized (this) {
if (args[index] != NOT_FOUND) {
if (args == activation.originalArgs) {
args = args.clone();
}
args[index] = value;
return;
}
}
}
}
super.put(index, start, value);
}
public void delete(int index)
{
if (0 <= index && index < args.length) {
synchronized (this) {
if (args[index] != NOT_FOUND) {
if (args == activation.originalArgs) {
args = args.clone();
}
args[index] = NOT_FOUND;
return;
}
}
}
super.delete(index);
}
// #string_id_map#
private static final int
Id_callee = 1,
Id_length = 2,
Id_caller = 3,
MAX_INSTANCE_ID = 3;
protected int getMaxInstanceId()
{
return MAX_INSTANCE_ID;
}
protected int findInstanceIdInfo(String s)
{
int id;
// #generated# Last update: 2007-05-09 08:15:04 EDT
L0: { id = 0; String X = null; int c;
if (s.length()==6) {
c=s.charAt(5);
if (c=='e') { X="callee";id=Id_callee; }
else if (c=='h') { X="length";id=Id_length; }
else if (c=='r') { X="caller";id=Id_caller; }
}
if (X!=null && X!=s && !X.equals(s)) id = 0;
break L0;
}
// #/generated#
if (id == 0) return super.findInstanceIdInfo(s);
int attr;
switch (id) {
case Id_callee:
case Id_caller:
case Id_length:
attr = DONTENUM;
break;
default: throw new IllegalStateException();
}
return instanceIdInfo(attr, id);
}
// #/string_id_map#
protected String getInstanceIdName(int id)
{
switch (id) {
case Id_callee: return "callee";
case Id_length: return "length";
case Id_caller: return "caller";
}
return null;
}
protected Object getInstanceIdValue(int id)
{
switch (id) {
case Id_callee: return calleeObj;
case Id_length: return lengthObj;
case Id_caller: {
Object value = callerObj;
if (value == UniqueTag.NULL_VALUE) { value = null; }
else if (value == null) {
NativeCall caller = activation.parentActivationCall;
if (caller != null) {
value = caller.get("arguments", caller);
}
}
return value;
}
}
return super.getInstanceIdValue(id);
}
protected void setInstanceIdValue(int id, Object value)
{
switch (id) {
case Id_callee: calleeObj = value; return;
case Id_length: lengthObj = value; return;
case Id_caller:
callerObj = (value != null) ? value : UniqueTag.NULL_VALUE;
return;
}
super.setInstanceIdValue(id, value);
}
Object[] getIds(boolean getAll)
{
Object[] ids = super.getIds(getAll);
if (getAll && args.length != 0) {
boolean[] present = null;
int extraCount = args.length;
for (int i = 0; i != ids.length; ++i) {
Object id = ids[i];
if (id instanceof Integer) {
int index = ((Integer)id).intValue();
if (0 <= index && index < args.length) {
if (present == null) {
present = new boolean[args.length];
}
if (!present[index]) {
present[index] = true;
extraCount--;
}
}
}
}
if (extraCount != 0) {
Object[] tmp = new Object[extraCount + ids.length];
System.arraycopy(ids, 0, tmp, extraCount, ids.length);
ids = tmp;
int offset = 0;
for (int i = 0; i != args.length; ++i) {
if (present == null || !present[i]) {
ids[offset] = new Integer(i);
++offset;
}
}
if (offset != extraCount) Kit.codeBug();
}
}
return ids;
}
// Fields to hold caller, callee and length properties,
// where NOT_FOUND value tags deleted properties.
// In addition if callerObj == NULL_VALUE, it tags null for scripts, as
// initial callerObj == null means access to caller arguments available
// only in JS <= 1.3 scripts
private Object callerObj;
private Object calleeObj;
private Object lengthObj;
private NativeCall activation;
// Initially args holds activation.getOriginalArgs(), but any modification
// of its elements triggers creation of a copy. If its element holds NOT_FOUND,
// it indicates deleted index, in which case super class is queried.
private Object[] args;
}
