org.jruby.runtime.ivars

Class VariableAccessor

java.lang.Object

org.jruby.runtime.ivars.VariableAccessor

Direct Known Subclasses:

FieldVariableAccessor, NonvolatileVariableAccessor, StampedVariableAccessor, SynchronizedVariableAccessor

public abstract class VariableAccessor
extends java.lang.Object

Abstraction of an accessor for instance or internal variables on Ruby objects. Subclasses specialize this implementation appropriate to the current JVM's capabilities and the mechanism for laying out variables.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	classId the symbol of the class associated with this variable
static VariableAccessor	DUMMY_ACCESSOR a dummy accessor that will always return null
protected int	index the index allocated for it in the variable table
protected java.lang.String	name the name of the variable
protected RubyClass	realClass the "real" class associated with this variable

Constructor Summary

Constructors

Constructor and Description
VariableAccessor(RubyClass realClass, java.lang.String name, int index, int classId) Construct a new VariableAccessor for the given "real" class, name, variable index, and class symbol.

Method Summary

Modifier and Type	Method and Description
java.lang.Object	get(java.lang.Object object) Retrieve the variable's value from the given object.
int	getClassId() Get the symbol of the class associated with this variable.
int	getIndex() Get the index allocated for this variable.
java.lang.String	getName() Get the name of this variable.
static java.lang.Object	getVariable(RubyBasicObject object, int index) Retrieve the variable's value from the given object.
void	set(java.lang.Object object, java.lang.Object value) Set the value for this variable in the given object.
java.lang.String	toString() Produce a string representation of this VariableAccessor.
boolean	verify(java.lang.Object object) Verify if this is the correct accessor for the given object.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

name

protected final java.lang.String name

the name of the variable

index

protected final int index

the index allocated for it in the variable table

classId

protected final int classId

the symbol of the class associated with this variable

realClass

protected final RubyClass realClass

the "real" class associated with this variable

DUMMY_ACCESSOR

public static final VariableAccessor DUMMY_ACCESSOR

a dummy accessor that will always return null

Constructor Detail

VariableAccessor

public VariableAccessor(RubyClass realClass,
                        java.lang.String name,
                        int index,
                        int classId)

Construct a new VariableAccessor for the given "real" class, name, variable index, and class symbol.

Parameters:

realClass - the "real" class

name - the variable's name

index - the variable's index

classId - the class's symbol

Method Detail

getClassId

public int getClassId()

Get the symbol of the class associated with this variable.

Returns:

this variable's class's id

getIndex

public int getIndex()

Get the index allocated for this variable.

Returns:

this variable's index

getName

public java.lang.String getName()

Get the name of this variable.

Returns:

this variable's name

get

public java.lang.Object get(java.lang.Object object)

Retrieve the variable's value from the given object.

Parameters:

object - the object from which to retrieve this variable

Returns:

the variable's value

getVariable

public static java.lang.Object getVariable(RubyBasicObject object,
                                           int index)

Retrieve the variable's value from the given object. This version is static, allowing it to be more direct, and accepts nnly with RubyBasicObject and subclasses along with the direct index of the variable.

Parameters:

object - the object from which to retrieve the variable

index - the index of the variable

Returns:

the variable's value

set

public void set(java.lang.Object object,
                java.lang.Object value)

Set the value for this variable in the given object.

Parameters:

object - the object into which to set this variable

value - the value of the variable

verify

public boolean verify(java.lang.Object object)

Verify if this is the correct accessor for the given object.

Parameters:

object - the object for which to test this accessor

Returns:

true if this is the correct accessor for the given object, false otherwise

toString

public java.lang.String toString()

Produce a string representation of this VariableAccessor.

Overrides:

toString in class java.lang.Object

Returns:

a string representation of this VariableAccessor