com.oracle.svm.core.heap

Class FeebleReference<T>

java.lang.Object

com.oracle.svm.core.heap.DiscoverableReference

com.oracle.svm.core.heap.FeebleReference<T>

public class FeebleReference<T>
extends DiscoverableReference

A feeble substitute for java.lang.ref.Reference. This is missing the notification methods, but has list methods. Fields for putting an instance on a list is here in the instance, because space can't be allocated during a collection. But they should only be used by list-manipulating classes.

The lifecycle of a FeebleReference:

• If the FeebleReference does not have a list:

  Stage	.referent	.list	.next
  At construction	referent	null	this
  At discovery	null	null	this

• If the FeebleReference does have a list:

Stage	.referent	.list	.next
At construction	referent	list	this
At discovery	null	list	this
Before pushing	null	null	this
After pushing	null	null	next
After popping	null	null	this

Note that after being pushed and popped a FeebleReference with a list is in the same state as a discovered FeebleReference without a list.

Nested Class Summary

Nested classes/interfaces inherited from class com.oracle.svm.core.heap.DiscoverableReference

DiscoverableReference.TestingBackDoor

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	FeebleReference(T referent, FeebleReferenceList<T> list) Constructor for subclasses.

Method Summary

Modifier and Type	Method and Description
FeebleReferenceList<T>	clearList() Clears the list, returning the previous value, which might be null.
static <T> FeebleReference<T>	factory(T referent, FeebleReferenceList<T> list)
T	get() Turn the referent into a strong reference.
FeebleReferenceList<T>	getList()
boolean	hasList()
boolean	isEnlisted() Is this FeebleReference on the list?
boolean	isFeeblReferenceInitialized() For GR-14335.

Methods inherited from class com.oracle.svm.core.heap.DiscoverableReference

clean, clear, getIsDiscovered, getNextDiscoverableReference, getReferentPointer, isDiscoverableReferenceInitialized, prependToDiscoveredReference, setReferentPointer

Methods inherited from class java.lang.Object

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

Constructor Detail

FeebleReference

protected FeebleReference(T referent,
                          FeebleReferenceList<T> list)

Constructor for subclasses.

Method Detail

factory

public static <T> FeebleReference<T> factory(T referent,
                                             FeebleReferenceList<T> list)

get

public T get()

Turn the referent into a strong reference.

isEnlisted

public boolean isEnlisted()

Is this FeebleReference on the list?

hasList

public boolean hasList()

getList

public FeebleReferenceList<T> getList()

clearList

public FeebleReferenceList<T> clearList()

Clears the list, returning the previous value, which might be null.

isFeeblReferenceInitialized

public boolean isFeeblReferenceInitialized()

For GR-14335.