org.mozilla.javascript.ScriptableObject Maven / Gradle / Ivy
/* -*- 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
* Bob Jervis
* Roger Lawrence
* Steve Weiss
*
* 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 ***** */
// API class
package org.mozilla.javascript;
import java.lang.reflect.*;
import java.util.Hashtable;
import java.io.*;
import org.mozilla.javascript.debug.DebuggableObject;
/**
* This is the default implementation of the Scriptable interface. This
* class provides convenient default behavior that makes it easier to
* define host objects.
*
* Various properties and methods of JavaScript objects can be conveniently
* defined using methods of ScriptableObject.
*
* Classes extending ScriptableObject must define the getClassName method.
*
* @see org.mozilla.javascript.Scriptable
* @author Norris Boyd
*/
public abstract class ScriptableObject implements Scriptable, Serializable,
DebuggableObject,
ConstProperties
{
/**
* The empty property attribute.
*
* Used by getAttributes() and setAttributes().
*
* @see org.mozilla.javascript.ScriptableObject#getAttributes(String)
* @see org.mozilla.javascript.ScriptableObject#setAttributes(String, int)
*/
public static final int EMPTY = 0x00;
/**
* Property attribute indicating assignment to this property is ignored.
*
* @see org.mozilla.javascript.ScriptableObject
* #put(String, Scriptable, Object)
* @see org.mozilla.javascript.ScriptableObject#getAttributes(String)
* @see org.mozilla.javascript.ScriptableObject#setAttributes(String, int)
*/
public static final int READONLY = 0x01;
/**
* Property attribute indicating property is not enumerated.
*
* Only enumerated properties will be returned by getIds().
*
* @see org.mozilla.javascript.ScriptableObject#getIds()
* @see org.mozilla.javascript.ScriptableObject#getAttributes(String)
* @see org.mozilla.javascript.ScriptableObject#setAttributes(String, int)
*/
public static final int DONTENUM = 0x02;
/**
* Property attribute indicating property cannot be deleted.
*
* @see org.mozilla.javascript.ScriptableObject#delete(String)
* @see org.mozilla.javascript.ScriptableObject#getAttributes(String)
* @see org.mozilla.javascript.ScriptableObject#setAttributes(String, int)
*/
public static final int PERMANENT = 0x04;
/**
* Property attribute indicating that this is a const property that has not
* been assigned yet. The first 'const' assignment to the property will
* clear this bit.
*/
public static final int UNINITIALIZED_CONST = 0x08;
public static final int CONST = PERMANENT|READONLY|UNINITIALIZED_CONST;
/**
* The prototype of this object.
*/
private Scriptable prototypeObject;
/**
* The parent scope of this object.
*/
private Scriptable parentScopeObject;
private static final Slot REMOVED = new Slot(null, 0, READONLY);
static {
REMOVED.wasDeleted = 1;
}
private transient Slot[] slots;
// If count >= 0, it gives number of keys or if count < 0,
// it indicates sealed object where ~count gives number of keys
private int count;
// cache; may be removed for smaller memory footprint
private transient Slot lastAccess = REMOVED;
// associated values are not serialized
private transient volatile Hashtable associatedValues;
private static final int SLOT_QUERY = 1;
private static final int SLOT_MODIFY = 2;
private static final int SLOT_REMOVE = 3;
private static final int SLOT_MODIFY_GETTER_SETTER = 4;
private static final int SLOT_MODIFY_CONST = 5;
private static class Slot implements Serializable
{
static final long serialVersionUID = -3539051633409902634L;
String name; // This can change due to caching
int indexOrHash;
private volatile short attributes;
transient volatile byte wasDeleted;
volatile Object value;
transient volatile Slot next;
Slot(String name, int indexOrHash, int attributes)
{
this.name = name;
this.indexOrHash = indexOrHash;
this.attributes = (short)attributes;
}
private void readObject(ObjectInputStream in)
throws IOException, ClassNotFoundException
{
in.defaultReadObject();
if (name != null) {
indexOrHash = name.hashCode();
}
}
final int getAttributes()
{
return attributes;
}
final synchronized void setAttributes(int value)
{
checkValidAttributes(value);
attributes = (short)value;
}
final void checkNotReadonly()
{
if ((attributes & READONLY) != 0) {
String str = (name != null ? name
: Integer.toString(indexOrHash));
throw Context.reportRuntimeError1("msg.modify.readonly", str);
}
}
}
private static final class GetterSlot extends Slot
{
static final long serialVersionUID = -4900574849788797588L;
Object getter;
Object setter;
GetterSlot(String name, int indexOrHash, int attributes)
{
super(name, indexOrHash, attributes);
}
}
static void checkValidAttributes(int attributes)
{
final int mask = READONLY | DONTENUM | PERMANENT | UNINITIALIZED_CONST;
if ((attributes & ~mask) != 0) {
throw new IllegalArgumentException(String.valueOf(attributes));
}
}
public ScriptableObject()
{
}
public ScriptableObject(Scriptable scope, Scriptable prototype)
{
if (scope == null)
throw new IllegalArgumentException();
parentScopeObject = scope;
prototypeObject = prototype;
}
/**
* Return the name of the class.
*
* This is typically the same name as the constructor.
* Classes extending ScriptableObject must implement this abstract
* method.
*/
public abstract String getClassName();
/**
* Returns true if the named property is defined.
*
* @param name the name of the property
* @param start the object in which the lookup began
* @return true if and only if the property was found in the object
*/
public boolean has(String name, Scriptable start)
{
return null != getSlot(name, 0, SLOT_QUERY);
}
/**
* Returns true if the property index is defined.
*
* @param index the numeric index for the property
* @param start the object in which the lookup began
* @return true if and only if the property was found in the object
*/
public boolean has(int index, Scriptable start)
{
return null != getSlot(null, index, SLOT_QUERY);
}
/**
* Returns the value of the named property or NOT_FOUND.
*
* If the property was created using defineProperty, the
* appropriate getter method is called.
*
* @param name the name of the property
* @param start the object in which the lookup began
* @return the value of the property (may be null), or NOT_FOUND
*/
public Object get(String name, Scriptable start)
{
return getImpl(name, 0, start);
}
/**
* Returns the value of the indexed property or NOT_FOUND.
*
* @param index the numeric index for the property
* @param start the object in which the lookup began
* @return the value of the property (may be null), or NOT_FOUND
*/
public Object get(int index, Scriptable start)
{
return getImpl(null, index, start);
}
/**
* Sets the value of the named property, creating it if need be.
*
* If the property was created using defineProperty, the
* appropriate setter method is called.
*
* If the property's attributes include READONLY, no action is
* taken.
* This method will actually set the property in the start
* object.
*
* @param name the name of the property
* @param start the object whose property is being set
* @param value value to set the property to
*/
public void put(String name, Scriptable start, Object value)
{
if (putImpl(name, 0, start, value, EMPTY))
return;
if (start == this) throw Kit.codeBug();
start.put(name, start, value);
}
/**
* Sets the value of the indexed property, creating it if need be.
*
* @param index the numeric index for the property
* @param start the object whose property is being set
* @param value value to set the property to
*/
public void put(int index, Scriptable start, Object value)
{
if (putImpl(null, index, start, value, EMPTY))
return;
if (start == this) throw Kit.codeBug();
start.put(index, start, value);
}
/**
* Removes a named property from the object.
*
* If the property is not found, or it has the PERMANENT attribute,
* no action is taken.
*
* @param name the name of the property
*/
public void delete(String name)
{
checkNotSealed(name, 0);
accessSlot(name, 0, SLOT_REMOVE);
}
/**
* Removes the indexed property from the object.
*
* If the property is not found, or it has the PERMANENT attribute,
* no action is taken.
*
* @param index the numeric index for the property
*/
public void delete(int index)
{
checkNotSealed(null, index);
accessSlot(null, index, SLOT_REMOVE);
}
/**
* Sets the value of the named const property, creating it if need be.
*
* If the property was created using defineProperty, the
* appropriate setter method is called.
*
* If the property's attributes include READONLY, no action is
* taken.
* This method will actually set the property in the start
* object.
*
* @param name the name of the property
* @param start the object whose property is being set
* @param value value to set the property to
*/
public void putConst(String name, Scriptable start, Object value)
{
if (putImpl(name, 0, start, value, READONLY))
return;
if (start == this) throw Kit.codeBug();
if (start instanceof ConstProperties)
((ConstProperties)start).putConst(name, start, value);
else
start.put(name, start, value);
}
public void defineConst(String name, Scriptable start)
{
if (putImpl(name, 0, start, Undefined.instance, UNINITIALIZED_CONST))
return;
if (start == this) throw Kit.codeBug();
if (start instanceof ConstProperties)
((ConstProperties)start).defineConst(name, start);
}
/**
* Returns true if the named property is defined as a const on this object.
* @param name
* @return true if the named property is defined as a const, false
* otherwise.
*/
public boolean isConst(String name)
{
Slot slot = getSlot(name, 0, SLOT_QUERY);
if (slot == null) {
return false;
}
return (slot.getAttributes() & (PERMANENT|READONLY)) ==
(PERMANENT|READONLY);
}
/**
* @deprecated Use {@link #getAttributes(String name)}. The engine always
* ignored the start argument.
*/
public final int getAttributes(String name, Scriptable start)
{
return getAttributes(name);
}
/**
* @deprecated Use {@link #getAttributes(int index)}. The engine always
* ignored the start argument.
*/
public final int getAttributes(int index, Scriptable start)
{
return getAttributes(index);
}
/**
* @deprecated Use {@link #setAttributes(String name, int attributes)}.
* The engine always ignored the start argument.
*/
public final void setAttributes(String name, Scriptable start,
int attributes)
{
setAttributes(name, attributes);
}
/**
* @deprecated Use {@link #setAttributes(int index, int attributes)}.
* The engine always ignored the start argument.
*/
public void setAttributes(int index, Scriptable start,
int attributes)
{
setAttributes(index, attributes);
}
/**
* Get the attributes of a named property.
*
* The property is specified by name
* as defined for has.
*
* @param name the identifier for the property
* @return the bitset of attributes
* @exception EvaluatorException if the named property is not found
* @see org.mozilla.javascript.ScriptableObject#has(String, Scriptable)
* @see org.mozilla.javascript.ScriptableObject#READONLY
* @see org.mozilla.javascript.ScriptableObject#DONTENUM
* @see org.mozilla.javascript.ScriptableObject#PERMANENT
* @see org.mozilla.javascript.ScriptableObject#EMPTY
*/
public int getAttributes(String name)
{
return findAttributeSlot(name, 0, SLOT_QUERY).getAttributes();
}
/**
* Get the attributes of an indexed property.
*
* @param index the numeric index for the property
* @exception EvaluatorException if the named property is not found
* is not found
* @return the bitset of attributes
* @see org.mozilla.javascript.ScriptableObject#has(String, Scriptable)
* @see org.mozilla.javascript.ScriptableObject#READONLY
* @see org.mozilla.javascript.ScriptableObject#DONTENUM
* @see org.mozilla.javascript.ScriptableObject#PERMANENT
* @see org.mozilla.javascript.ScriptableObject#EMPTY
*/
public int getAttributes(int index)
{
return findAttributeSlot(null, index, SLOT_QUERY).getAttributes();
}
/**
* Set the attributes of a named property.
*
* The property is specified by name
* as defined for has.
*
* The possible attributes are READONLY, DONTENUM,
* and PERMANENT. Combinations of attributes
* are expressed by the bitwise OR of attributes.
* EMPTY is the state of no attributes set. Any unused
* bits are reserved for future use.
*
* @param name the name of the property
* @param attributes the bitset of attributes
* @exception EvaluatorException if the named property is not found
* @see org.mozilla.javascript.Scriptable#has(String, Scriptable)
* @see org.mozilla.javascript.ScriptableObject#READONLY
* @see org.mozilla.javascript.ScriptableObject#DONTENUM
* @see org.mozilla.javascript.ScriptableObject#PERMANENT
* @see org.mozilla.javascript.ScriptableObject#EMPTY
*/
public void setAttributes(String name, int attributes)
{
checkNotSealed(name, 0);
findAttributeSlot(name, 0, SLOT_MODIFY).setAttributes(attributes);
}
/**
* Set the attributes of an indexed property.
*
* @param index the numeric index for the property
* @param attributes the bitset of attributes
* @exception EvaluatorException if the named property is not found
* @see org.mozilla.javascript.Scriptable#has(String, Scriptable)
* @see org.mozilla.javascript.ScriptableObject#READONLY
* @see org.mozilla.javascript.ScriptableObject#DONTENUM
* @see org.mozilla.javascript.ScriptableObject#PERMANENT
* @see org.mozilla.javascript.ScriptableObject#EMPTY
*/
public void setAttributes(int index, int attributes)
{
checkNotSealed(null, index);
findAttributeSlot(null, index, SLOT_MODIFY).setAttributes(attributes);
}
/**
* XXX: write docs.
*/
public void setGetterOrSetter(String name, int index,
Callable getterOrSeter, boolean isSetter)
{
if (name != null && index != 0)
throw new IllegalArgumentException(name);
checkNotSealed(name, index);
GetterSlot gslot = (GetterSlot)getSlot(name, index,
SLOT_MODIFY_GETTER_SETTER);
gslot.checkNotReadonly();
if (isSetter) {
gslot.setter = getterOrSeter;
} else {
gslot.getter = getterOrSeter;
}
gslot.value = Undefined.instance;
}
/**
* Get the getter or setter for a given property. Used by __lookupGetter__
* and __lookupSetter__.
*
* @param name Name of the object. If nonnull, index must be 0.
* @param index Index of the object. If nonzero, name must be null.
* @param isSetter If true, return the setter, otherwise return the getter.
* @exception IllegalArgumentException if both name and index are nonnull
* and nonzero respectively.
* @return Null if the property does not exist. Otherwise returns either
* the getter or the setter for the property, depending on
* the value of isSetter (may be undefined if unset).
*/
public Object getGetterOrSetter(String name, int index, boolean isSetter)
{
if (name != null && index != 0)
throw new IllegalArgumentException(name);
Slot slot = getSlot(name, index, SLOT_QUERY);
if (slot == null)
return null;
if (slot instanceof GetterSlot) {
GetterSlot gslot = (GetterSlot)slot;
Object result = isSetter ? gslot.setter : gslot.getter;
return result != null ? result : Undefined.instance;
} else
return Undefined.instance;
}
/**
* Returns whether a property is a getter or a setter
* @param name property name
* @param index property index
* @param setter true to check for a setter, false for a getter
* @return whether the property is a getter or a setter
*/
protected boolean isGetterOrSetter(String name, int index, boolean setter) {
Slot slot = getSlot(name, index, SLOT_QUERY);
if (slot instanceof GetterSlot) {
if (setter && ((GetterSlot)slot).setter != null) return true;
if (!setter && ((GetterSlot)slot).getter != null) return true;
}
return false;
}
void addLazilyInitializedValue(String name, int index,
LazilyLoadedCtor init, int attributes)
{
if (name != null && index != 0)
throw new IllegalArgumentException(name);
checkNotSealed(name, index);
GetterSlot gslot = (GetterSlot)getSlot(name, index,
SLOT_MODIFY_GETTER_SETTER);
gslot.setAttributes(attributes);
gslot.getter = null;
gslot.setter = null;
gslot.value = init;
}
/**
* Returns the prototype of the object.
*/
public Scriptable getPrototype()
{
return prototypeObject;
}
/**
* Sets the prototype of the object.
*/
public void setPrototype(Scriptable m)
{
prototypeObject = m;
}
/**
* Returns the parent (enclosing) scope of the object.
*/
public Scriptable getParentScope()
{
return parentScopeObject;
}
/**
* Sets the parent (enclosing) scope of the object.
*/
public void setParentScope(Scriptable m)
{
parentScopeObject = m;
}
/**
* Returns an array of ids for the properties of the object.
*
*
Any properties with the attribute DONTENUM are not listed.
*
* @return an array of java.lang.Objects with an entry for every
* listed property. Properties accessed via an integer index will
* have a corresponding
* Integer entry in the returned array. Properties accessed by
* a String will have a String entry in the returned array.
*/
public Object[] getIds() {
return getIds(false);
}
/**
* Returns an array of ids for the properties of the object.
*
*
All properties, even those with attribute DONTENUM, are listed.
*
* @return an array of java.lang.Objects with an entry for every
* listed property. Properties accessed via an integer index will
* have a corresponding
* Integer entry in the returned array. Properties accessed by
* a String will have a String entry in the returned array.
*/
public Object[] getAllIds() {
return getIds(true);
}
/**
* Implements the [[DefaultValue]] internal method.
*
*
Note that the toPrimitive conversion is a no-op for
* every type other than Object, for which [[DefaultValue]]
* is called. See ECMA 9.1.
*
* A hint of null means "no hint".
*
* @param typeHint the type hint
* @return the default value for the object
*
* See ECMA 8.6.2.6.
*/
public Object getDefaultValue(Class typeHint)
{
return getDefaultValue(this, typeHint);
}
public static Object getDefaultValue(Scriptable object, Class typeHint)
{
Context cx = null;
for (int i=0; i < 2; i++) {
boolean tryToString;
if (typeHint == ScriptRuntime.StringClass) {
tryToString = (i == 0);
} else {
tryToString = (i == 1);
}
String methodName;
Object[] args;
if (tryToString) {
methodName = "toString";
args = ScriptRuntime.emptyArgs;
} else {
methodName = "valueOf";
args = new Object[1];
String hint;
if (typeHint == null) {
hint = "undefined";
} else if (typeHint == ScriptRuntime.StringClass) {
hint = "string";
} else if (typeHint == ScriptRuntime.ScriptableClass) {
hint = "object";
} else if (typeHint == ScriptRuntime.FunctionClass) {
hint = "function";
} else if (typeHint == ScriptRuntime.BooleanClass
|| typeHint == Boolean.TYPE)
{
hint = "boolean";
} else if (typeHint == ScriptRuntime.NumberClass ||
typeHint == ScriptRuntime.ByteClass ||
typeHint == Byte.TYPE ||
typeHint == ScriptRuntime.ShortClass ||
typeHint == Short.TYPE ||
typeHint == ScriptRuntime.IntegerClass ||
typeHint == Integer.TYPE ||
typeHint == ScriptRuntime.FloatClass ||
typeHint == Float.TYPE ||
typeHint == ScriptRuntime.DoubleClass ||
typeHint == Double.TYPE)
{
hint = "number";
} else {
throw Context.reportRuntimeError1(
"msg.invalid.type", typeHint.toString());
}
args[0] = hint;
}
Object v = getProperty(object, methodName);
if (!(v instanceof Function))
continue;
Function fun = (Function) v;
if (cx == null)
cx = Context.getContext();
v = fun.call(cx, fun.getParentScope(), object, args);
if (v != null) {
if (!(v instanceof Scriptable)) {
return v;
}
if (typeHint == ScriptRuntime.ScriptableClass
|| typeHint == ScriptRuntime.FunctionClass)
{
return v;
}
if (tryToString && v instanceof Wrapper) {
// Let a wrapped java.lang.String pass for a primitive
// string.
Object u = ((Wrapper)v).unwrap();
if (u instanceof String)
return u;
}
}
}
// fall through to error
String arg = (typeHint == null) ? "undefined" : typeHint.getName();
throw ScriptRuntime.typeError1("msg.default.value", arg);
}
/**
* Implements the instanceof operator.
*
*
This operator has been proposed to ECMA.
*
* @param instance The value that appeared on the LHS of the instanceof
* operator
* @return true if "this" appears in value's prototype chain
*
*/
public boolean hasInstance(Scriptable instance) {
// Default for JS objects (other than Function) is to do prototype
// chasing. This will be overridden in NativeFunction and non-JS
// objects.
return ScriptRuntime.jsDelegatesTo(instance, this);
}
/**
* Emulate the SpiderMonkey (and Firefox) feature of allowing
* custom objects to avoid detection by normal "object detection"
* code patterns. This is used to implement document.all.
* See https://bugzilla.mozilla.org/show_bug.cgi?id=412247.
* This is an analog to JOF_DETECTING from SpiderMonkey; see
* https://bugzilla.mozilla.org/show_bug.cgi?id=248549.
* Other than this special case, embeddings should return false.
* @return true if this object should avoid object detection
* @since 1.7R1
*/
public boolean avoidObjectDetection() {
return false;
}
/**
* Custom == operator.
* Must return {@link Scriptable#NOT_FOUND} if this object does not
* have custom equality operator for the given value,
* Boolean.TRUE if this object is equivalent to value,
* Boolean.FALSE if this object is not equivalent to
* value.
*
* The default implementation returns Boolean.TRUE
* if this == value or {@link Scriptable#NOT_FOUND} otherwise.
* It indicates that by default custom equality is available only if
* value is this in which case true is returned.
*/
protected Object equivalentValues(Object value)
{
return (this == value) ? Boolean.TRUE : Scriptable.NOT_FOUND;
}
/**
* Defines JavaScript objects from a Java class that implements Scriptable.
*
* If the given class has a method
*
* static void init(Context cx, Scriptable scope, boolean sealed);
*
* or its compatibility form
*
* static void init(Scriptable scope);
*
* then it is invoked and no further initialization is done.
*
* However, if no such a method is found, then the class's constructors and
* methods are used to initialize a class in the following manner.
*
* First, the zero-parameter constructor of the class is called to
* create the prototype. If no such constructor exists,
* a {@link EvaluatorException} is thrown.
*
* Next, all methods are scanned for special prefixes that indicate that they
* have special meaning for defining JavaScript objects.
* These special prefixes are
*
* jsFunction_ for a JavaScript function
* jsStaticFunction_ for a JavaScript function that
* is a property of the constructor
* jsGet_ for a getter of a JavaScript property
* jsSet_ for a setter of a JavaScript property
* jsConstructor for a JavaScript function that
* is the constructor
*
*
* If the method's name begins with "jsFunction_", a JavaScript function
* is created with a name formed from the rest of the Java method name
* following "jsFunction_". So a Java method named "jsFunction_foo" will
* define a JavaScript method "foo". Calling this JavaScript function
* will cause the Java method to be called. The parameters of the method
* must be of number and types as defined by the FunctionObject class.
* The JavaScript function is then added as a property
* of the prototype.
*
* If the method's name begins with "jsStaticFunction_", it is handled
* similarly except that the resulting JavaScript function is added as a
* property of the constructor object. The Java method must be static.
*
* If the method's name begins with "jsGet_" or "jsSet_", the method is
* considered to define a property. Accesses to the defined property
* will result in calls to these getter and setter methods. If no
* setter is defined, the property is defined as READONLY.
*
* If the method's name is "jsConstructor", the method is
* considered to define the body of the constructor. Only one
* method of this name may be defined.
* If no method is found that can serve as constructor, a Java
* constructor will be selected to serve as the JavaScript
* constructor in the following manner. If the class has only one
* Java constructor, that constructor is used to define
* the JavaScript constructor. If the the class has two constructors,
* one must be the zero-argument constructor (otherwise an
* {@link EvaluatorException} would have already been thrown
* when the prototype was to be created). In this case
* the Java constructor with one or more parameters will be used
* to define the JavaScript constructor. If the class has three
* or more constructors, an {@link EvaluatorException}
* will be thrown.
*
* Finally, if there is a method
*
* static void finishInit(Scriptable scope, FunctionObject constructor,
* Scriptable prototype)
*
* it will be called to finish any initialization. The scope
* argument will be passed, along with the newly created constructor and
* the newly created prototype.
*
* @param scope The scope in which to define the constructor.
* @param clazz The Java class to use to define the JavaScript objects
* and properties.
* @exception IllegalAccessException if access is not available
* to a reflected class member
* @exception InstantiationException if unable to instantiate
* the named class
* @exception InvocationTargetException if an exception is thrown
* during execution of methods of the named class
* @see org.mozilla.javascript.Function
* @see org.mozilla.javascript.FunctionObject
* @see org.mozilla.javascript.ScriptableObject#READONLY
* @see org.mozilla.javascript.ScriptableObject
* #defineProperty(String, Class, int)
*/
public static void defineClass(Scriptable scope, Class clazz)
throws IllegalAccessException, InstantiationException,
InvocationTargetException
{
defineClass(scope, clazz, false, false);
}
/**
* Defines JavaScript objects from a Java class, optionally
* allowing sealing.
*
* Similar to defineClass(Scriptable scope, Class clazz)
* except that sealing is allowed. An object that is sealed cannot have
* properties added or removed. Note that sealing is not allowed in
* the current ECMA/ISO language specification, but is likely for
* the next version.
*
* @param scope The scope in which to define the constructor.
* @param clazz The Java class to use to define the JavaScript objects
* and properties. The class must implement Scriptable.
* @param sealed Whether or not to create sealed standard objects that
* cannot be modified.
* @exception IllegalAccessException if access is not available
* to a reflected class member
* @exception InstantiationException if unable to instantiate
* the named class
* @exception InvocationTargetException if an exception is thrown
* during execution of methods of the named class
* @since 1.4R3
*/
public static void defineClass(Scriptable scope, Class clazz,
boolean sealed)
throws IllegalAccessException, InstantiationException,
InvocationTargetException
{
defineClass(scope, clazz, sealed, false);
}
/**
* Defines JavaScript objects from a Java class, optionally
* allowing sealing and mapping of Java inheritance to JavaScript
* prototype-based inheritance.
*
* Similar to defineClass(Scriptable scope, Class clazz)
* except that sealing and inheritance mapping are allowed. An object
* that is sealed cannot have properties added or removed. Note that
* sealing is not allowed in the current ECMA/ISO language specification,
* but is likely for the next version.
*
* @param scope The scope in which to define the constructor.
* @param clazz The Java class to use to define the JavaScript objects
* and properties. The class must implement Scriptable.
* @param sealed Whether or not to create sealed standard objects that
* cannot be modified.
* @param mapInheritance Whether or not to map Java inheritance to
* JavaScript prototype-based inheritance.
* @return the class name for the prototype of the specified class
* @exception IllegalAccessException if access is not available
* to a reflected class member
* @exception InstantiationException if unable to instantiate
* the named class
* @exception InvocationTargetException if an exception is thrown
* during execution of methods of the named class
* @since 1.6R2
*/
public static String defineClass(Scriptable scope, Class clazz,
boolean sealed, boolean mapInheritance)
throws IllegalAccessException, InstantiationException,
InvocationTargetException
{
BaseFunction ctor = buildClassCtor(scope, clazz, sealed,
mapInheritance);
if (ctor == null)
return null;
String name = ctor.getClassPrototype().getClassName();
defineProperty(scope, name, ctor, ScriptableObject.DONTENUM);
return name;
}
static BaseFunction buildClassCtor(Scriptable scope, Class clazz,
boolean sealed,
boolean mapInheritance)
throws IllegalAccessException, InstantiationException,
InvocationTargetException
{
Method[] methods = FunctionObject.getMethodList(clazz);
for (int i=0; i < methods.length; i++) {
Method method = methods[i];
if (!method.getName().equals("init"))
continue;
Class[] parmTypes = method.getParameterTypes();
if (parmTypes.length == 3 &&
parmTypes[0] == ScriptRuntime.ContextClass &&
parmTypes[1] == ScriptRuntime.ScriptableClass &&
parmTypes[2] == Boolean.TYPE &&
Modifier.isStatic(method.getModifiers()))
{
Object args[] = { Context.getContext(), scope,
sealed ? Boolean.TRUE : Boolean.FALSE };
method.invoke(null, args);
return null;
}
if (parmTypes.length == 1 &&
parmTypes[0] == ScriptRuntime.ScriptableClass &&
Modifier.isStatic(method.getModifiers()))
{
Object args[] = { scope };
method.invoke(null, args);
return null;
}
}
// If we got here, there isn't an "init" method with the right
// parameter types.
Constructor[] ctors = clazz.getConstructors();
Constructor protoCtor = null;
for (int i=0; i < ctors.length; i++) {
if (ctors[i].getParameterTypes().length == 0) {
protoCtor = ctors[i];
break;
}
}
if (protoCtor == null) {
throw Context.reportRuntimeError1(
"msg.zero.arg.ctor", clazz.getName());
}
Scriptable proto = (Scriptable) protoCtor.newInstance(ScriptRuntime.emptyArgs);
String className = proto.getClassName();
// Set the prototype's prototype, trying to map Java inheritance to JS
// prototype-based inheritance if requested to do so.
Scriptable superProto = null;
if (mapInheritance) {
Class superClass = clazz.getSuperclass();
if (ScriptRuntime.ScriptableClass.isAssignableFrom(superClass)
&& !Modifier.isAbstract(superClass.getModifiers())) {
String name = ScriptableObject.defineClass(scope, superClass, sealed, mapInheritance);
if (name != null) {
superProto = ScriptableObject.getClassPrototype(scope, name);
}
}
}
if (superProto == null) {
superProto = ScriptableObject.getObjectPrototype(scope);
}
proto.setPrototype(superProto);
// Find out whether there are any methods that begin with
// "js". If so, then only methods that begin with special
// prefixes will be defined as JavaScript entities.
final String functionPrefix = "jsFunction_";
final String staticFunctionPrefix = "jsStaticFunction_";
final String getterPrefix = "jsGet_";
final String setterPrefix = "jsSet_";
final String ctorName = "jsConstructor";
Member ctorMember = FunctionObject.findSingleMethod(methods, ctorName);
if (ctorMember == null) {
if (ctors.length == 1) {
ctorMember = ctors[0];
} else if (ctors.length == 2) {
if (ctors[0].getParameterTypes().length == 0)
ctorMember = ctors[1];
else if (ctors[1].getParameterTypes().length == 0)
ctorMember = ctors[0];
}
if (ctorMember == null) {
throw Context.reportRuntimeError1(
"msg.ctor.multiple.parms", clazz.getName());
}
}
FunctionObject ctor = new FunctionObject(className, ctorMember, scope);
if (ctor.isVarArgsMethod()) {
throw Context.reportRuntimeError1
("msg.varargs.ctor", ctorMember.getName());
}
ctor.initAsConstructor(scope, proto);
Method finishInit = null;
for (int i=0; i < methods.length; i++) {
if (methods[i] == ctorMember) {
continue;
}
String name = methods[i].getName();
if (name.equals("finishInit")) {
Class[] parmTypes = methods[i].getParameterTypes();
if (parmTypes.length == 3 &&
parmTypes[0] == ScriptRuntime.ScriptableClass &&
parmTypes[1] == FunctionObject.class &&
parmTypes[2] == ScriptRuntime.ScriptableClass &&
Modifier.isStatic(methods[i].getModifiers()))
{
finishInit = methods[i];
continue;
}
}
// ignore any compiler generated methods.
if (name.indexOf('$') != -1)
continue;
if (name.equals(ctorName))
continue;
String prefix = null;
if (name.startsWith(functionPrefix)) {
prefix = functionPrefix;
} else if (name.startsWith(staticFunctionPrefix)) {
prefix = staticFunctionPrefix;
if (!Modifier.isStatic(methods[i].getModifiers())) {
throw Context.reportRuntimeError(
"jsStaticFunction must be used with static method.");
}
} else if (name.startsWith(getterPrefix)) {
prefix = getterPrefix;
} else if (name.startsWith(setterPrefix)) {
prefix = setterPrefix;
} else {
continue;
}
name = name.substring(prefix.length());
if (prefix == setterPrefix)
continue; // deal with set when we see get
if (prefix == getterPrefix) {
if (!(proto instanceof ScriptableObject)) {
throw Context.reportRuntimeError2(
"msg.extend.scriptable",
proto.getClass().toString(), name);
}
Method setter = FunctionObject.findSingleMethod(
methods,
setterPrefix + name);
int attr = ScriptableObject.PERMANENT |
ScriptableObject.DONTENUM |
(setter != null ? 0
: ScriptableObject.READONLY);
((ScriptableObject) proto).defineProperty(name, null,
methods[i], setter,
attr);
continue;
}
FunctionObject f = new FunctionObject(name, methods[i], proto);
if (f.isVarArgsConstructor()) {
throw Context.reportRuntimeError1
("msg.varargs.fun", ctorMember.getName());
}
Scriptable dest = prefix == staticFunctionPrefix
? ctor
: proto;
defineProperty(dest, name, f, DONTENUM);
if (sealed) {
f.sealObject();
}
}
// Call user code to complete initialization if necessary.
if (finishInit != null) {
Object[] finishArgs = { scope, ctor, proto };
finishInit.invoke(null, finishArgs);
}
// Seal the object if necessary.
if (sealed) {
ctor.sealObject();
if (proto instanceof ScriptableObject) {
((ScriptableObject) proto).sealObject();
}
}
return ctor;
}
/**
* Define a JavaScript property.
*
* Creates the property with an initial value and sets its attributes.
*
* @param propertyName the name of the property to define.
* @param value the initial value of the property
* @param attributes the attributes of the JavaScript property
* @see org.mozilla.javascript.Scriptable#put(String, Scriptable, Object)
*/
public void defineProperty(String propertyName, Object value,
int attributes)
{
checkNotSealed(propertyName, 0);
put(propertyName, this, value);
setAttributes(propertyName, attributes);
}
/**
* Utility method to add properties to arbitrary Scriptable object.
* If destination is instance of ScriptableObject, calls
* defineProperty there, otherwise calls put in destination
* ignoring attributes
*/
public static void defineProperty(Scriptable destination,
String propertyName, Object value,
int attributes)
{
if (!(destination instanceof ScriptableObject)) {
destination.put(propertyName, destination, value);
return;
}
ScriptableObject so = (ScriptableObject)destination;
so.defineProperty(propertyName, value, attributes);
}
/**
* Utility method to add properties to arbitrary Scriptable object.
* If destination is instance of ScriptableObject, calls
* defineProperty there, otherwise calls put in destination
* ignoring attributes
*/
public static void defineConstProperty(Scriptable destination,
String propertyName)
{
if (destination instanceof ConstProperties) {
ConstProperties cp = (ConstProperties)destination;
cp.defineConst(propertyName, destination);
} else
defineProperty(destination, propertyName, Undefined.instance, CONST);
}
/**
* Define a JavaScript property with getter and setter side effects.
*
* If the setter is not found, the attribute READONLY is added to
* the given attributes.
*
* The getter must be a method with zero parameters, and the setter, if
* found, must be a method with one parameter.
*
* @param propertyName the name of the property to define. This name
* also affects the name of the setter and getter
* to search for. If the propertyId is "foo", then
* clazz will be searched for "getFoo"
* and "setFoo" methods.
* @param clazz the Java class to search for the getter and setter
* @param attributes the attributes of the JavaScript property
* @see org.mozilla.javascript.Scriptable#put(String, Scriptable, Object)
*/
public void defineProperty(String propertyName, Class clazz,
int attributes)
{
int length = propertyName.length();
if (length == 0) throw new IllegalArgumentException();
char[] buf = new char[3 + length];
propertyName.getChars(0, length, buf, 3);
buf[3] = Character.toUpperCase(buf[3]);
buf[0] = 'g';
buf[1] = 'e';
buf[2] = 't';
String getterName = new String(buf);
buf[0] = 's';
String setterName = new String(buf);
Method[] methods = FunctionObject.getMethodList(clazz);
Method getter = FunctionObject.findSingleMethod(methods, getterName);
Method setter = FunctionObject.findSingleMethod(methods, setterName);
if (setter == null)
attributes |= ScriptableObject.READONLY;
defineProperty(propertyName, null, getter,
setter == null ? null : setter, attributes);
}
/**
* Define a JavaScript property.
*
* Use this method only if you wish to define getters and setters for
* a given property in a ScriptableObject. To create a property without
* special getter or setter side effects, use
* defineProperty(String,int).
*
* If setter is null, the attribute READONLY is added to
* the given attributes.
*
* Several forms of getters or setters are allowed. In all cases the
* type of the value parameter can be any one of the following types:
* Object, String, boolean, Scriptable, byte, short, int, long, float,
* or double. The runtime will perform appropriate conversions based
* upon the type of the parameter (see description in FunctionObject).
* The first forms are nonstatic methods of the class referred to
* by 'this':
*
* Object getFoo();
* void setFoo(SomeType value);
* Next are static methods that may be of any class; the object whose
* property is being accessed is passed in as an extra argument:
*
* static Object getFoo(Scriptable obj);
* static void setFoo(Scriptable obj, SomeType value);
* Finally, it is possible to delegate to another object entirely using
* the delegateTo parameter. In this case the methods are
* nonstatic methods of the class delegated to, and the object whose
* property is being accessed is passed in as an extra argument:
*
* Object getFoo(Scriptable obj);
* void setFoo(Scriptable obj, SomeType value);
*
* @param propertyName the name of the property to define.
* @param delegateTo an object to call the getter and setter methods on,
* or null, depending on the form used above.
* @param getter the method to invoke to get the value of the property
* @param setter the method to invoke to set the value of the property
* @param attributes the attributes of the JavaScript property
*/
public void defineProperty(String propertyName, Object delegateTo,
Method getter, Method setter, int attributes)
{
MemberBox getterBox = null;
if (getter != null) {
getterBox = new MemberBox(getter);
boolean delegatedForm;
if (!Modifier.isStatic(getter.getModifiers())) {
delegatedForm = (delegateTo != null);
getterBox.delegateTo = delegateTo;
} else {
delegatedForm = true;
// Ignore delegateTo for static getter but store
// non-null delegateTo indicator.
getterBox.delegateTo = Void.TYPE;
}
String errorId = null;
Class[] parmTypes = getter.getParameterTypes();
if (parmTypes.length == 0) {
if (delegatedForm) {
errorId = "msg.obj.getter.parms";
}
} else if (parmTypes.length == 1) {
Object argType = parmTypes[0];
// Allow ScriptableObject for compatibility
if (!(argType == ScriptRuntime.ScriptableClass ||
argType == ScriptRuntime.ScriptableObjectClass))
{
errorId = "msg.bad.getter.parms";
} else if (!delegatedForm) {
errorId = "msg.bad.getter.parms";
}
} else {
errorId = "msg.bad.getter.parms";
}
if (errorId != null) {
throw Context.reportRuntimeError1(errorId, getter.toString());
}
}
MemberBox setterBox = null;
if (setter != null) {
if (setter.getReturnType() != Void.TYPE)
throw Context.reportRuntimeError1("msg.setter.return",
setter.toString());
setterBox = new MemberBox(setter);
boolean delegatedForm;
if (!Modifier.isStatic(setter.getModifiers())) {
delegatedForm = (delegateTo != null);
setterBox.delegateTo = delegateTo;
} else {
delegatedForm = true;
// Ignore delegateTo for static setter but store
// non-null delegateTo indicator.
setterBox.delegateTo = Void.TYPE;
}
String errorId = null;
Class[] parmTypes = setter.getParameterTypes();
if (parmTypes.length == 1) {
if (delegatedForm) {
errorId = "msg.setter2.expected";
}
} else if (parmTypes.length == 2) {
Object argType = parmTypes[0];
// Allow ScriptableObject for compatibility
if (!(argType == ScriptRuntime.ScriptableClass ||
argType == ScriptRuntime.ScriptableObjectClass))
{
errorId = "msg.setter2.parms";
} else if (!delegatedForm) {
errorId = "msg.setter1.parms";
}
} else {
errorId = "msg.setter.parms";
}
if (errorId != null) {
throw Context.reportRuntimeError1(errorId, setter.toString());
}
}
GetterSlot gslot = (GetterSlot)getSlot(propertyName, 0,
SLOT_MODIFY_GETTER_SETTER);
gslot.setAttributes(attributes);
gslot.getter = getterBox;
gslot.setter = setterBox;
}
/**
* Search for names in a class, adding the resulting methods
* as properties.
*
* Uses reflection to find the methods of the given names. Then
* FunctionObjects are constructed from the methods found, and
* are added to this object as properties with the given names.
*
* @param names the names of the Methods to add as function properties
* @param clazz the class to search for the Methods
* @param attributes the attributes of the new properties
* @see org.mozilla.javascript.FunctionObject
*/
public void defineFunctionProperties(String[] names, Class clazz,
int attributes)
{
Method[] methods = FunctionObject.getMethodList(clazz);
for (int i=0; i < names.length; i++) {
String name = names[i];
Method m = FunctionObject.findSingleMethod(methods, name);
if (m == null) {
throw Context.reportRuntimeError2(
"msg.method.not.found", name, clazz.getName());
}
FunctionObject f = new FunctionObject(name, m, this);
defineProperty(name, f, attributes);
}
}
/**
* Get the Object.prototype property.
* See ECMA 15.2.4.
*/
public static Scriptable getObjectPrototype(Scriptable scope) {
return getClassPrototype(scope, "Object");
}
/**
* Get the Function.prototype property.
* See ECMA 15.3.4.
*/
public static Scriptable getFunctionPrototype(Scriptable scope) {
return getClassPrototype(scope, "Function");
}
/**
* Get the prototype for the named class.
*
* For example, getClassPrototype(s, "Date") will first
* walk up the parent chain to find the outermost scope, then will
* search that scope for the Date constructor, and then will
* return Date.prototype. If any of the lookups fail, or
* the prototype is not a JavaScript object, then null will
* be returned.
*
* @param scope an object in the scope chain
* @param className the name of the constructor
* @return the prototype for the named class, or null if it
* cannot be found.
*/
public static Scriptable getClassPrototype(Scriptable scope,
String className)
{
scope = getTopLevelScope(scope);
Object ctor = getProperty(scope, className);
Object proto;
if (ctor instanceof BaseFunction) {
proto = ((BaseFunction)ctor).getPrototypeProperty();
} else if (ctor instanceof Scriptable) {
Scriptable ctorObj = (Scriptable)ctor;
proto = ctorObj.get("prototype", ctorObj);
} else {
return null;
}
if (proto instanceof Scriptable) {
return (Scriptable)proto;
}
return null;
}
/**
* Get the global scope.
*
*
Walks the parent scope chain to find an object with a null
* parent scope (the global object).
*
* @param obj a JavaScript object
* @return the corresponding global scope
*/
public static Scriptable getTopLevelScope(Scriptable obj)
{
for (;;) {
Scriptable parent = obj.getParentScope();
if (parent == null) {
return obj;
}
obj = parent;
}
}
/**
* Seal this object.
*
* A sealed object may not have properties added or removed. Once
* an object is sealed it may not be unsealed.
*
* @since 1.4R3
*/
public synchronized void sealObject() {
if (count >= 0) {
count = ~count;
}
}
/**
* Return true if this object is sealed.
*
* It is an error to attempt to add or remove properties to
* a sealed object.
*
* @return true if sealed, false otherwise.
* @since 1.4R3
*/
public final boolean isSealed() {
return count < 0;
}
private void checkNotSealed(String name, int index)
{
if (!isSealed())
return;
String str = (name != null) ? name : Integer.toString(index);
throw Context.reportRuntimeError1("msg.modify.sealed", str);
}
/**
* Gets a named property from an object or any object in its prototype chain.
*
* Searches the prototype chain for a property named name.
*
* @param obj a JavaScript object
* @param name a property name
* @return the value of a property with name name found in
* obj or any object in its prototype chain, or
* Scriptable.NOT_FOUND if not found
* @since 1.5R2
*/
public static Object getProperty(Scriptable obj, String name)
{
Scriptable start = obj;
Object result;
do {
result = obj.get(name, start);
if (result != Scriptable.NOT_FOUND)
break;
obj = obj.getPrototype();
} while (obj != null);
return result;
}
/**
* Gets an indexed property from an object or any object in its prototype chain.
*
* Searches the prototype chain for a property with integral index
* index. Note that if you wish to look for properties with numerical
* but non-integral indicies, you should use getProperty(Scriptable,String) with
* the string value of the index.
*
* @param obj a JavaScript object
* @param index an integral index
* @return the value of a property with index index found in
* obj or any object in its prototype chain, or
* Scriptable.NOT_FOUND if not found
* @since 1.5R2
*/
public static Object getProperty(Scriptable obj, int index)
{
Scriptable start = obj;
Object result;
do {
result = obj.get(index, start);
if (result != Scriptable.NOT_FOUND)
break;
obj = obj.getPrototype();
} while (obj != null);
return result;
}
/**
* Returns whether a named property is defined in an object or any object
* in its prototype chain.
*
* Searches the prototype chain for a property named name.
*
* @param obj a JavaScript object
* @param name a property name
* @return the true if property was found
* @since 1.5R2
*/
public static boolean hasProperty(Scriptable obj, String name)
{
return null != getBase(obj, name);
}
/**
* If hasProperty(obj, name) would return true, then if the property that
* was found is compatible with the new property, this method just returns.
* If the property is not compatible, then an exception is thrown.
*
* A property redefinition is incompatible if the first definition was a
* const declaration or if this one is. They are compatible only if neither
* was const.
*/
public static void redefineProperty(Scriptable obj, String name,
boolean isConst)
{
Scriptable base = getBase(obj, name);
if (base == null)
return;
if (base instanceof ConstProperties) {
ConstProperties cp = (ConstProperties)base;
if (cp.isConst(name))
throw Context.reportRuntimeError1("msg.const.redecl", name);
}
if (isConst)
throw Context.reportRuntimeError1("msg.var.redecl", name);
}
/**
* Returns whether an indexed property is defined in an object or any object
* in its prototype chain.
*
* Searches the prototype chain for a property with index index.
*
* @param obj a JavaScript object
* @param index a property index
* @return the true if property was found
* @since 1.5R2
*/
public static boolean hasProperty(Scriptable obj, int index)
{
return null != getBase(obj, index);
}
/**
* Puts a named property in an object or in an object in its prototype chain.
*
* Searches for the named property in the prototype chain. If it is found,
* the value of the property in obj is changed through a call
* to {@link Scriptable#put(String, Scriptable, Object)} on the
* prototype passing obj as the start argument.
* This allows the prototype to veto the property setting in case the
* prototype defines the property with [[ReadOnly]] attribute. If the
* property is not found, it is added in obj.
* @param obj a JavaScript object
* @param name a property name
* @param value any JavaScript value accepted by Scriptable.put
* @since 1.5R2
*/
public static void putProperty(Scriptable obj, String name, Object value)
{
Scriptable base = getBase(obj, name);
if (base == null)
base = obj;
base.put(name, obj, value);
}
/**
* Puts a named property in an object or in an object in its prototype chain.
*
* Searches for the named property in the prototype chain. If it is found,
* the value of the property in obj is changed through a call
* to {@link Scriptable#put(String, Scriptable, Object)} on the
* prototype passing obj as the start argument.
* This allows the prototype to veto the property setting in case the
* prototype defines the property with [[ReadOnly]] attribute. If the
* property is not found, it is added in obj.
* @param obj a JavaScript object
* @param name a property name
* @param value any JavaScript value accepted by Scriptable.put
* @since 1.5R2
*/
public static void putConstProperty(Scriptable obj, String name, Object value)
{
Scriptable base = getBase(obj, name);
if (base == null)
base = obj;
if (base instanceof ConstProperties)
((ConstProperties)base).putConst(name, obj, value);
}
/**
* Puts an indexed property in an object or in an object in its prototype chain.
*
* Searches for the indexed property in the prototype chain. If it is found,
* the value of the property in obj is changed through a call
* to {@link Scriptable#put(int, Scriptable, Object)} on the prototype
* passing obj as the start argument. This allows
* the prototype to veto the property setting in case the prototype defines
* the property with [[ReadOnly]] attribute. If the property is not found,
* it is added in obj.
* @param obj a JavaScript object
* @param index a property index
* @param value any JavaScript value accepted by Scriptable.put
* @since 1.5R2
*/
public static void putProperty(Scriptable obj, int index, Object value)
{
Scriptable base = getBase(obj, index);
if (base == null)
base = obj;
base.put(index, obj, value);
}
/**
* Removes the property from an object or its prototype chain.
*
* Searches for a property with name in obj or
* its prototype chain. If it is found, the object's delete
* method is called.
* @param obj a JavaScript object
* @param name a property name
* @return true if the property doesn't exist or was successfully removed
* @since 1.5R2
*/
public static boolean deleteProperty(Scriptable obj, String name)
{
Scriptable base = getBase(obj, name);
if (base == null)
return true;
base.delete(name);
return !base.has(name, obj);
}
/**
* Removes the property from an object or its prototype chain.
*
* Searches for a property with index in obj or
* its prototype chain. If it is found, the object's delete
* method is called.
* @param obj a JavaScript object
* @param index a property index
* @return true if the property doesn't exist or was successfully removed
* @since 1.5R2
*/
public static boolean deleteProperty(Scriptable obj, int index)
{
Scriptable base = getBase(obj, index);
if (base == null)
return true;
base.delete(index);
return !base.has(index, obj);
}
/**
* Returns an array of all ids from an object and its prototypes.
*
* @param obj a JavaScript object
* @return an array of all ids from all object in the prototype chain.
* If a given id occurs multiple times in the prototype chain,
* it will occur only once in this list.
* @since 1.5R2
*/
public static Object[] getPropertyIds(Scriptable obj)
{
if (obj == null) {
return ScriptRuntime.emptyArgs;
}
Object[] result = obj.getIds();
ObjToIntMap map = null;
for (;;) {
obj = obj.getPrototype();
if (obj == null) {
break;
}
Object[] ids = obj.getIds();
if (ids.length == 0) {
continue;
}
if (map == null) {
if (result.length == 0) {
result = ids;
continue;
}
map = new ObjToIntMap(result.length + ids.length);
for (int i = 0; i != result.length; ++i) {
map.intern(result[i]);
}
result = null; // Allow to GC the result
}
for (int i = 0; i != ids.length; ++i) {
map.intern(ids[i]);
}
}
if (map != null) {
result = map.getKeys();
}
return result;
}
/**
* Call a method of an object.
* @param obj the JavaScript object
* @param methodName the name of the function property
* @param args the arguments for the call
*
* @see Context#getCurrentContext()
*/
public static Object callMethod(Scriptable obj, String methodName,
Object[] args)
{
return callMethod(null, obj, methodName, args);
}
/**
* Call a method of an object.
* @param cx the Context object associated with the current thread.
* @param obj the JavaScript object
* @param methodName the name of the function property
* @param args the arguments for the call
*/
public static Object callMethod(Context cx, Scriptable obj,
String methodName,
Object[] args)
{
Object funObj = getProperty(obj, methodName);
if (!(funObj instanceof Function)) {
throw ScriptRuntime.notFunctionError(obj, methodName);
}
Function fun = (Function)funObj;
// XXX: What should be the scope when calling funObj?
// The following favor scope stored in the object on the assumption
// that is more useful especially under dynamic scope setup.
// An alternative is to check for dynamic scope flag
// and use ScriptableObject.getTopLevelScope(fun) if the flag is not
// set. But that require access to Context and messy code
// so for now it is not checked.
Scriptable scope = ScriptableObject.getTopLevelScope(obj);
if (cx != null) {
return fun.call(cx, scope, obj, args);
} else {
return Context.call(null, fun, scope, obj, args);
}
}
private static Scriptable getBase(Scriptable obj, String name)
{
do {
if (obj.has(name, obj))
break;
obj = obj.getPrototype();
} while(obj != null);
return obj;
}
private static Scriptable getBase(Scriptable obj, int index)
{
do {
if (obj.has(index, obj))
break;
obj = obj.getPrototype();
} while(obj != null);
return obj;
}
/**
* Get arbitrary application-specific value associated with this object.
* @param key key object to select particular value.
* @see #associateValue(Object key, Object value)
*/
public final Object getAssociatedValue(Object key)
{
Hashtable h = associatedValues;
if (h == null)
return null;
return h.get(key);
}
/**
* Get arbitrary application-specific value associated with the top scope
* of the given scope.
* The method first calls {@link #getTopLevelScope(Scriptable scope)}
* and then searches the prototype chain of the top scope for the first
* object containing the associated value with the given key.
*
* @param scope the starting scope.
* @param key key object to select particular value.
* @see #getAssociatedValue(Object key)
*/
public static Object getTopScopeValue(Scriptable scope, Object key)
{
scope = ScriptableObject.getTopLevelScope(scope);
for (;;) {
if (scope instanceof ScriptableObject) {
ScriptableObject so = (ScriptableObject)scope;
Object value = so.getAssociatedValue(key);
if (value != null) {
return value;
}
}
scope = scope.getPrototype();
if (scope == null) {
return null;
}
}
}
/**
* Associate arbitrary application-specific value with this object.
* Value can only be associated with the given object and key only once.
* The method ignores any subsequent attempts to change the already
* associated value.
*
The associated values are not serialized.
* @param key key object to select particular value.
* @param value the value to associate
* @return the passed value if the method is called first time for the
* given key or old value for any subsequent calls.
* @see #getAssociatedValue(Object key)
*/
public final Object associateValue(Object key, Object value)
{
if (value == null) throw new IllegalArgumentException();
Hashtable h = associatedValues;
if (h == null) {
synchronized (this) {
h = associatedValues;
if (h == null) {
h = new Hashtable();
associatedValues = h;
}
}
}
return Kit.initHash(h, key, value);
}
private Object getImpl(String name, int index, Scriptable start)
{
Slot slot = getSlot(name, index, SLOT_QUERY);
if (slot == null) {
return Scriptable.NOT_FOUND;
}
if (!(slot instanceof GetterSlot)) {
return slot.value;
}
Object getterObj = ((GetterSlot)slot).getter;
if (getterObj != null) {
if (getterObj instanceof MemberBox) {
MemberBox nativeGetter = (MemberBox)getterObj;
Object getterThis;
Object[] args;
if (nativeGetter.delegateTo == null) {
getterThis = start;
args = ScriptRuntime.emptyArgs;
} else {
getterThis = nativeGetter.delegateTo;
args = new Object[] { start };
}
return nativeGetter.invoke(getterThis, args);
} else {
Function f = (Function)getterObj;
Context cx = Context.getContext();
return f.call(cx, f.getParentScope(), start,
ScriptRuntime.emptyArgs);
}
}
Object value = slot.value;
if (value instanceof LazilyLoadedCtor) {
LazilyLoadedCtor initializer = (LazilyLoadedCtor)value;
try {
initializer.init();
} finally {
value = initializer.getValue();
slot.value = value;
}
}
return value;
}
/**
*
* @param name
* @param index
* @param start
* @param value
* @param constFlag EMPTY means normal put. UNINITIALIZED_CONST means
* defineConstProperty. READONLY means const initialization expression.
* @return false if this != start and no slot was found. true if this == start
* or this != start and a READONLY slot was found.
*/
private boolean putImpl(String name, int index, Scriptable start,
Object value, int constFlag)
{
Slot slot;
if (this != start) {
slot = getSlot(name, index, SLOT_QUERY);
if (slot == null) {
return false;
}
} else {
checkNotSealed(name, index);
// either const hoisted declaration or initialization
if (constFlag != EMPTY) {
slot = getSlot(name, index, SLOT_MODIFY_CONST);
int attr = slot.getAttributes();
if ((attr & READONLY) == 0)
throw Context.reportRuntimeError1("msg.var.redecl", name);
if ((attr & UNINITIALIZED_CONST) != 0) {
slot.value = value;
// clear the bit on const initialization
if (constFlag != UNINITIALIZED_CONST)
slot.setAttributes(attr & ~UNINITIALIZED_CONST);
}
return true;
}
slot = getSlot(name, index, SLOT_MODIFY);
}
if ((slot.getAttributes() & READONLY) != 0)
return true;
if (slot instanceof GetterSlot) {
Object setterObj = ((GetterSlot)slot).setter;
if (setterObj != null) {
Context cx = Context.getContext();
if (setterObj instanceof MemberBox) {
MemberBox nativeSetter = (MemberBox)setterObj;
Class pTypes[] = nativeSetter.argTypes;
// XXX: cache tag since it is already calculated in
// defineProperty ?
Class valueType = pTypes[pTypes.length - 1];
int tag = FunctionObject.getTypeTag(valueType);
Object actualArg = FunctionObject.convertArg(cx, start,
value, tag);
Object setterThis;
Object[] args;
if (nativeSetter.delegateTo == null) {
setterThis = start;
args = new Object[] { actualArg };
} else {
setterThis = nativeSetter.delegateTo;
args = new Object[] { start, actualArg };
}
nativeSetter.invoke(setterThis, args);
} else {
Function f = (Function)setterObj;
f.call(cx, f.getParentScope(), start,
new Object[] { value });
}
return true;
}
}
if (this == start) {
slot.value = value;
return true;
} else {
return false;
}
}
private Slot findAttributeSlot(String name, int index, int accessType)
{
Slot slot = getSlot(name, index, accessType);
if (slot == null) {
String str = (name != null ? name : Integer.toString(index));
throw Context.reportRuntimeError1("msg.prop.not.found", str);
}
return slot;
}
/**
* Locate the slot with given name or index.
*
* @param name property name or null if slot holds spare array index.
* @param index index or 0 if slot holds property name.
*/
private Slot getSlot(String name, int index, int accessType)
{
Slot slot;
// Query last access cache and check that it was not deleted.
lastAccessCheck:
{
slot = lastAccess;
if (name != null) {
if (name != slot.name)
break lastAccessCheck;
// No String.equals here as successful slot search update
// name object with fresh reference of the same string.
} else {
if (slot.name != null || index != slot.indexOrHash)
break lastAccessCheck;
}
if (slot.wasDeleted != 0)
break lastAccessCheck;
if (accessType == SLOT_MODIFY_GETTER_SETTER &&
!(slot instanceof GetterSlot))
break lastAccessCheck;
return slot;
}
slot = accessSlot(name, index, accessType);
if (slot != null) {
// Update the cache
lastAccess = slot;
}
return slot;
}
private Slot accessSlot(String name, int index, int accessType)
{
int indexOrHash = (name != null ? name.hashCode() : index);
if (accessType == SLOT_QUERY ||
accessType == SLOT_MODIFY ||
accessType == SLOT_MODIFY_CONST ||
accessType == SLOT_MODIFY_GETTER_SETTER)
{
// Check the hashtable without using synchronization
Slot[] slotsLocalRef = slots; // Get stable local reference
if (slotsLocalRef == null) {
if (accessType == SLOT_QUERY)
return null;
} else {
int tableSize = slotsLocalRef.length;
int slotIndex = getSlotIndex(tableSize, indexOrHash);
Slot slot = slotsLocalRef[slotIndex];
while (slot != null) {
String sname = slot.name;
if (sname != null) {
if (sname == name)
break;
if (name != null && indexOrHash == slot.indexOrHash) {
if (name.equals(sname)) {
// This will avoid calling String.equals when
// slot is accessed with same string object
// next time.
slot.name = name;
break;
}
}
} else if (name == null &&
indexOrHash == slot.indexOrHash) {
break;
}
slot = slot.next;
}
if (accessType == SLOT_QUERY) {
return slot;
} else if (accessType == SLOT_MODIFY) {
if (slot != null)
return slot;
} else if (accessType == SLOT_MODIFY_GETTER_SETTER) {
if (slot instanceof GetterSlot)
return slot;
} else if (accessType == SLOT_MODIFY_CONST) {
if (slot != null)
return slot;
}
}
// A new slot has to be inserted or the old has to be replaced
// by GetterSlot. Time to synchronize.
synchronized (this) {
// Refresh local ref if another thread triggered grow
slotsLocalRef = slots;
int insertPos;
if (count == 0) {
// Always throw away old slots if any on empty insert
slotsLocalRef = new Slot[5];
slots = slotsLocalRef;
insertPos = getSlotIndex(slotsLocalRef.length, indexOrHash);
} else {
int tableSize = slotsLocalRef.length;
insertPos = getSlotIndex(tableSize, indexOrHash);
Slot prev = slotsLocalRef[insertPos];
Slot slot = prev;
while (slot != null) {
if (slot.indexOrHash == indexOrHash &&
(slot.name == name ||
(name != null && name.equals(slot.name))))
{
break;
}
prev = slot;
slot = slot.next;
}
if (slot != null) {
// Another thread just added a slot with same
// name/index before this one entered synchronized
// block. This is a race in application code and
// probably indicates bug there. But for the hashtable
// implementation it is harmless with the only
// complication is the need to replace the added slot
// if we need GetterSlot and the old one is not.
if (accessType == SLOT_MODIFY_GETTER_SETTER &&
!(slot instanceof GetterSlot))
{
GetterSlot newSlot = new GetterSlot(name, indexOrHash,
slot.getAttributes());
newSlot.value = slot.value;
newSlot.next = slot.next;
if (prev == slot) {
slotsLocalRef[insertPos] = newSlot;
} else {
prev.next = newSlot;
}
slot.wasDeleted = (byte)1;
if (slot == lastAccess) {
lastAccess = REMOVED;
}
slot = newSlot;
} else if (accessType == SLOT_MODIFY_CONST) {
return null;
}
return slot;
}
// Check if the table is not too full before inserting.
if (4 * (count + 1) > 3 * slotsLocalRef.length) {
slotsLocalRef = new Slot[slotsLocalRef.length * 2 + 1];
copyTable(slots, slotsLocalRef, count);
slots = slotsLocalRef;
insertPos = getSlotIndex(slotsLocalRef.length,
indexOrHash);
}
}
Slot newSlot = (accessType == SLOT_MODIFY_GETTER_SETTER
? new GetterSlot(name, indexOrHash, 0)
: new Slot(name, indexOrHash, 0));
if (accessType == SLOT_MODIFY_CONST)
newSlot.setAttributes(CONST);
++count;
addKnownAbsentSlot(slotsLocalRef, newSlot, insertPos);
return newSlot;
}
} else if (accessType == SLOT_REMOVE) {
synchronized (this) {
Slot[] slotsLocalRef = slots;
if (count != 0) {
int tableSize = slots.length;
int slotIndex = getSlotIndex(tableSize, indexOrHash);
Slot prev = slotsLocalRef[slotIndex];
Slot slot = prev;
while (slot != null) {
if (slot.indexOrHash == indexOrHash &&
(slot.name == name ||
(name != null && name.equals(slot.name))))
{
break;
}
prev = slot;
slot = slot.next;
}
if (slot != null && (slot.getAttributes() & PERMANENT) == 0) {
count--;
if (prev == slot) {
slotsLocalRef[slotIndex] = slot.next;
} else {
prev.next = slot.next;
}
// Mark the slot as removed to handle a case when
// another thread manages to put just removed slot
// into lastAccess cache.
slot.wasDeleted = (byte)1;
if (slot == lastAccess) {
lastAccess = REMOVED;
}
}
}
}
return null;
} else {
throw Kit.codeBug();
}
}
private static int getSlotIndex(int tableSize, int indexOrHash)
{
return (indexOrHash & 0x7fffffff) % tableSize;
}
// Must be inside synchronized (this)
private static void copyTable(Slot[] slots, Slot[] newSlots, int count)
{
if (count == 0) throw Kit.codeBug();
int tableSize = newSlots.length;
int i = slots.length;
for (;;) {
--i;
Slot slot = slots[i];
while (slot != null) {
int insertPos = getSlotIndex(tableSize, slot.indexOrHash);
Slot next = slot.next;
addKnownAbsentSlot(newSlots, slot, insertPos);
slot.next = null;
slot = next;
if (--count == 0)
return;
}
}
}
/**
* Add slot with keys that are known to absent from the table.
* This is an optimization to use when inserting into empty table,
* after table growth or during deserialization.
*/
private static void addKnownAbsentSlot(Slot[] slots, Slot slot, int insertPos)
{
if (slots[insertPos] == null) {
slots[insertPos] = slot;
} else {
Slot prev = slots[insertPos];
while (prev.next != null) {
prev = prev.next;
}
prev.next = slot;
}
}
Object[] getIds(boolean getAll) {
Slot[] s = slots;
Object[] a = ScriptRuntime.emptyArgs;
if (s == null)
return a;
int c = 0;
for (int i=0; i < s.length; i++) {
Slot slot = s[i];
while (slot != null) {
if (getAll || (slot.getAttributes() & DONTENUM) == 0) {
if (c == 0)
a = new Object[s.length];
a[c++] = (slot.name != null ? (Object) slot.name
: new Integer(slot.indexOrHash));
}
slot = slot.next;
}
}
if (c == a.length)
return a;
Object[] result = new Object[c];
System.arraycopy(a, 0, result, 0, c);
return result;
}
private synchronized void writeObject(ObjectOutputStream out)
throws IOException
{
out.defaultWriteObject();
int objectsCount = count;
if (objectsCount < 0) {
// "this" was sealed
objectsCount = ~objectsCount;
}
if (objectsCount == 0) {
out.writeInt(0);
} else {
out.writeInt(slots.length);
for (int i = 0; i < slots.length; ++i) {
Slot slot = slots[i];
while (slot != null) {
out.writeObject(slot);
slot = slot.next;
if (--objectsCount == 0)
return;
}
}
}
}
private void readObject(ObjectInputStream in)
throws IOException, ClassNotFoundException
{
in.defaultReadObject();
lastAccess = REMOVED;
int tableSize = in.readInt();
if (tableSize != 0) {
slots = new Slot[tableSize];
int objectsCount = count;
if (objectsCount < 0) {
// "this" was sealed
objectsCount = ~objectsCount;
}
for (int i = 0; i != objectsCount; ++i) {
Slot slot = (Slot)in.readObject();
int slotIndex = getSlotIndex(tableSize, slot.indexOrHash);
addKnownAbsentSlot(slots, slot, slotIndex);
}
}
}
}