org.mozilla.javascript
Class FunctionObject

java.lang.Object
  |
  +--org.mozilla.javascript.ScriptableObject
        |
        +--org.mozilla.javascript.IdScriptable
              |
              +--org.mozilla.javascript.BaseFunction
                    |
                    +--org.mozilla.javascript.FunctionObject

All Implemented Interfaces:

Callable, org.mozilla.javascript.debug.DebuggableObject, Function, org.mozilla.javascript.IdFunctionMaster, Scriptable, java.io.Serializable

public class FunctionObject

extends org.mozilla.javascript.BaseFunction

See Also:

Serialized Form

Field Summary

static int	JAVA_BOOLEAN_TYPE
static int	JAVA_DOUBLE_TYPE
static int	JAVA_INT_TYPE
static int	JAVA_OBJECT_TYPE
static int	JAVA_SCRIPTABLE_TYPE
static int	JAVA_STRING_TYPE
static int	JAVA_UNSUPPORTED_TYPE

Fields inherited from class org.mozilla.javascript.ScriptableObject

DONTENUM, EMPTY, PERMANENT, READONLY

Fields inherited from interface org.mozilla.javascript.Scriptable

NOT_FOUND

Constructor Summary

FunctionObject(java.lang.String name, java.lang.reflect.Member methodOrConstructor, Scriptable scope)
Create a JavaScript function object from a Java method.

Method Summary

void	addAsConstructor(Scriptable scope, Scriptable prototype) Define this function as a JavaScript constructor.
java.lang.Object	call(Context cx, Scriptable scope, Scriptable thisObj, java.lang.Object[] args) Performs conversions on argument types if needed and invokes the underlying Java method or constructor.
static java.lang.Object	convertArg(Context cx, Scriptable scope, java.lang.Object arg, java.lang.Class desired) Deprecated. Use getTypeTag(Class) and convertArg(Context, Scriptable, Object, int) for type convertion.
static java.lang.Object	convertArg(Context cx, Scriptable scope, java.lang.Object arg, int typeTag)
Scriptable	createObject(Context cx, Scriptable scope) Return new Scriptable instance using the default constructor for the class of the underlying Java method.
int	getArity() Return the value defined by the method used to construct the object (number of parameters of the method, or 1 if the method is a "varargs" form).
int	getLength() Return the same value as getArity().
java.lang.reflect.Member	getMethodOrConstructor() Get Java method or constructor this function represent.
static int	getTypeTag(java.lang.Class type)

Methods inherited from class org.mozilla.javascript.BaseFunction

construct, execMethod, getClassName, getFunctionName, hasInstance, methodArity, setImmunePrototypeProperty

Methods inherited from class org.mozilla.javascript.IdScriptable

addAsPrototype, defineProperty, delete, get, getAttributes, has, put, setAttributes

Methods inherited from class org.mozilla.javascript.ScriptableObject

associateValue, callMethod, defineClass, defineClass, defineFunctionProperties, defineProperty, defineProperty, defineProperty, delete, deleteProperty, deleteProperty, get, getAllIds, getAssociatedValue, getAttributes, getAttributes, getAttributes, getClassPrototype, getDefaultValue, getFunctionPrototype, getIds, getObjectPrototype, getParentScope, getProperty, getProperty, getPropertyIds, getPrototype, getTopLevelScope, has, hasProperty, hasProperty, isSealed, put, putProperty, putProperty, sealObject, setAttributes, setAttributes, setAttributes, setParentScope, setPrototype

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.mozilla.javascript.Scriptable

delete, delete, get, get, getDefaultValue, getIds, getParentScope, getPrototype, has, has, put, put, setParentScope, setPrototype

Field Detail

JAVA_UNSUPPORTED_TYPE

public static final int JAVA_UNSUPPORTED_TYPE

JAVA_STRING_TYPE

public static final int JAVA_STRING_TYPE

JAVA_INT_TYPE

public static final int JAVA_INT_TYPE

JAVA_BOOLEAN_TYPE

public static final int JAVA_BOOLEAN_TYPE

JAVA_DOUBLE_TYPE

public static final int JAVA_DOUBLE_TYPE

JAVA_SCRIPTABLE_TYPE

public static final int JAVA_SCRIPTABLE_TYPE

JAVA_OBJECT_TYPE

public static final int JAVA_OBJECT_TYPE

Constructor Detail

FunctionObject

public FunctionObject(java.lang.String name,
                      java.lang.reflect.Member methodOrConstructor,
                      Scriptable scope)

Create a JavaScript function object from a Java method.

The member argument must be either a java.lang.reflect.Method or a java.lang.reflect.Constructor and must match one of two forms.

The first form is a member with zero or more parameters of the following types: Object, String, boolean, Scriptable, int, or double. The Long type is not supported because the double representation of a long (which is the EMCA-mandated storage type for Numbers) may lose precision. If the member is a Method, the return value must be void or one of the types allowed for parameters.

The runtime will perform appropriate conversions based upon the type of the parameter. A parameter type of Object specifies that no conversions are to be done. A parameter of type String will use Context.toString to convert arguments. Similarly, parameters of type double, boolean, and Scriptable will cause Context.toNumber, Context.toBoolean, and Context.toObject, respectively, to be called.

If the method is not static, the Java 'this' value will correspond to the JavaScript 'this' value. Any attempt to call the function with a 'this' value that is not of the right Java type will result in an error.

The second form is the variable arguments (or "varargs") form. If the FunctionObject will be used as a constructor, the member must have the following parameters

      (Context cx, Object[] args, Function ctorObj,
       boolean inNewExpr)

and if it is a Method, be static and return an Object result.

Otherwise, if the FunctionObject will not be used to define a constructor, the member must be a static Method with parameters (Context cx, Scriptable thisObj, Object[] args, Function funObj)

 and an Object result.


 When the function varargs form is called as part of a function call,
 the args parameter contains the
 arguments, with thisObj
 set to the JavaScript 'this' value. funObj
 is the function object for the invoked function.


 When the constructor varargs form is called or invoked while evaluating
 a new expression, args contains the
 arguments, ctorObj refers to this FunctionObject, and
 inNewExpr is true if and only if  a new
 expression caused the call. This supports defining a function that
 has different behavior when called as a constructor than when
 invoked as a normal function call. (For example, the Boolean
 constructor, when called as a function,
 will convert to boolean rather than creating a new object.)

Parameters:
name - the name of the function
methodOrConstructor - a java.lang.reflect.Method or a java.lang.reflect.Constructor
                            that defines the object
scope - enclosing scope of function
See Also: 
Scriptable

Method Detail

getTypeTag

public static int getTypeTag(java.lang.Class type)

Returns:

One of JAVA_*_TYPE constants to indicate desired type or JAVA_UNSUPPORTED_TYPE if the convertion is not possible

convertArg

public static java.lang.Object convertArg(Context cx,
                                          Scriptable scope,
                                          java.lang.Object arg,
                                          int typeTag)

getArity

public int getArity()

Return the value defined by the method used to construct the object (number of parameters of the method, or 1 if the method is a "varargs" form).

Overrides:

getArity in class org.mozilla.javascript.BaseFunction

getLength

public int getLength()

Return the same value as getArity().

Overrides:

getLength in class org.mozilla.javascript.BaseFunction

getMethodOrConstructor

public java.lang.reflect.Member getMethodOrConstructor()

Get Java method or constructor this function represent.

addAsConstructor

public void addAsConstructor(Scriptable scope,
                             Scriptable prototype)

Define this function as a JavaScript constructor.

Sets up the "prototype" and "constructor" properties. Also calls setParent and setPrototype with appropriate values. Then adds the function object as a property of the given scope, using prototype.getClassName() as the name of the property.

Parameters:

scope - the scope in which to define the constructor (typically the global object)

prototype - the prototype object

See Also:

Scriptable.setParentScope(org.mozilla.javascript.Scriptable), Scriptable.setPrototype(org.mozilla.javascript.Scriptable), Scriptable.getClassName()

convertArg

public static java.lang.Object convertArg(Context cx,
                                          Scriptable scope,
                                          java.lang.Object arg,
                                          java.lang.Class desired)

Deprecated. Use getTypeTag(Class) and convertArg(Context, Scriptable, Object, int) for type convertion.

call

public java.lang.Object call(Context cx,
                             Scriptable scope,
                             Scriptable thisObj,
                             java.lang.Object[] args)
                      throws JavaScriptException

Performs conversions on argument types if needed and invokes the underlying Java method or constructor.

Implements Function.call.

Overrides:

call in class org.mozilla.javascript.BaseFunction

Throws:

JavaScriptException - if the underlying Java method or constructor threw an exception

See Also:

Function.call(org.mozilla.javascript.Context, org.mozilla.javascript.Scriptable, org.mozilla.javascript.Scriptable, java.lang.Object[])

createObject

public Scriptable createObject(Context cx,
                               Scriptable scope)

Return new Scriptable instance using the default constructor for the class of the underlying Java method. Return null to indicate that the call method should be used to create new objects.

Overrides:

createObject in class org.mozilla.javascript.BaseFunction