Uses of Class java.lang.ref.Reference (Java SE 11 & JDK 11 )

Packages that use Reference
Package Description

java.lang.ref
Provides reference-object classes, which support a limited degree of interaction with the garbage collector.

Uses of Reference in java.lang.ref

Subclasses of Reference in java.lang.ref
Modifier and Type	Class	Description
`class`	`PhantomReference<T>`	Phantom reference objects, which are enqueued after the collector determines that their referents may otherwise be reclaimed.
`class`	`SoftReference<T>`	Soft reference objects, which are cleared at the discretion of the garbage collector in response to memory demand.
`class`	`WeakReference<T>`	Weak reference objects, which do not prevent their referents from being made finalizable, finalized, and then reclaimed.

Methods in java.lang.ref that return Reference
Modifier and Type	Method	Description
`Reference<? extends T>`	ReferenceQueue.`poll()`	Polls this queue to see if a reference object is available.
`Reference<? extends T>`	ReferenceQueue.`remove()`	Removes the next reference object in this queue, blocking until one becomes available.
`Reference<? extends T>`	ReferenceQueue.`remove(long timeout)`	Removes the next reference object in this queue, blocking until either one becomes available or the given timeout period expires.