org.vmmagic.unboxed

Class ObjectReference

java.lang.Object

org.vmmagic.unboxed.ObjectReference

public final class ObjectReference
extends Object

The object reference type is used by the runtime system and collector to represent a type that holds a reference to a single object. We use a separate type instead of the Java Object type for coding clarity, to make a clear distinction between objects the VM is written in, and objects that the VM is managing. No operations that can not be completed in pure Java should be allowed on Object.

Field Summary

Fields

Modifier and Type	Field and Description
private Object	data The object field.

Constructor Summary

Constructors

Constructor and Description
ObjectReference()

Method Summary

Modifier and Type	Method and Description
static ObjectReference	fromObject(Object obj) Convert from an object to a reference.
boolean	isNull()
static ObjectReference	nullReference()
Address	toAddress()
Object	toObject() Convert from an reference to an object.

Methods inherited from class java.lang.Object

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

Field Detail

data

private Object data

The object field.

Constructor Detail

ObjectReference

public ObjectReference()

Method Detail

fromObject

public static ObjectReference fromObject(Object obj)

Convert from an object to a reference.

Parameters:

obj - The object

Returns:

The corresponding reference

nullReference

public static ObjectReference nullReference()

Returns:

a null reference

toObject

public Object toObject()

Convert from an reference to an object. Note: this is a JikesRVM specific extension to vmmagic.

Returns:

The object

toAddress

public Address toAddress()

Returns:

a heap address for the object.

isNull

public boolean isNull()

Returns:

whether this is a null reference