public class Undefined
extends java.lang.Object
implements java.io.Serializable
We represent "undefined" internally using two static objects -- "Undefined.instance" and SCRIPTABLE_UNDEFINED. Java code that needs to make something undefined should generally use the first, and use the second if a Scriptable object is absolutely required.
Java code that needs to test whether something is undefined must use the "isUndefined" method because of the multiple internal representations.
| Modifier and Type | Field and Description | 
|---|---|
| static java.lang.Object | instanceThis is the standard value for "undefined" in Rhino. | 
| static Scriptable | SCRIPTABLE_UNDEFINEDAn alternate representation of undefined, to be used only when we need to pass it to a method
 that takes as Scriptable as a parameter. | 
| Modifier and Type | Method and Description | 
|---|---|
| boolean | equals(java.lang.Object obj) | 
| int | hashCode() | 
| static boolean | isUndefined(java.lang.Object obj)Safely test whether "obj" is undefined. | 
| java.lang.Object | readResolve() | 
public static final java.lang.Object instance
public static final Scriptable SCRIPTABLE_UNDEFINED
public java.lang.Object readResolve()
public boolean equals(java.lang.Object obj)
equals in class java.lang.Objectpublic int hashCode()
hashCode in class java.lang.Objectpublic static boolean isUndefined(java.lang.Object obj)