Package aQute.bnd.memoize

Class ReferenceMemoizingSupplier<T>

java.lang.Object

aQute.bnd.memoize.ReferenceMemoizingSupplier<T>

All Implemented Interfaces:

Memoize<T>, java.util.function.Supplier<T>

class ReferenceMemoizingSupplier<T>
extends java.lang.Object
implements Memoize<T>

The object can exist in one of two states:

• cleared which means memoized holds a cleared reference. This is the initial state. The object transitions to this state if the garbage collector clears the reference. From this state, the object transitions to valued when @{code get} is called.
• valued which means memoized holds a reference with a value.

Field Summary

Fields

Modifier and Type	Field	Description
private java.lang.ref.Reference<? extends T>	memoized
private java.util.function.Function<? super T,? extends java.lang.ref.Reference<? extends T>>	reference
private java.util.function.Supplier<? extends T>	supplier

Constructor Summary

Constructors

Constructor	Description
ReferenceMemoizingSupplier(java.util.function.Supplier<? extends T> supplier, java.util.function.Function<? super T,? extends java.lang.ref.Reference<? extends T>> reference)

Method Summary

Modifier and Type	Method	Description
T	get()	Get the memoized value.
boolean	isPresent()	If a value is memoized, return true.
T	peek()	Peek the memoized value, if any.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface aQute.bnd.memoize.Memoize

accept, filter, flatMap, ifPresent, map

Field Detail

supplier

private final java.util.function.Supplier<? extends T> supplier

reference

private final java.util.function.Function<? super T,? extends java.lang.ref.Reference<? extends T>> reference

memoized

private volatile java.lang.ref.Reference<? extends T> memoized

Constructor Detail

ReferenceMemoizingSupplier

ReferenceMemoizingSupplier(java.util.function.Supplier<? extends T> supplier,
                           java.util.function.Function<? super T,? extends java.lang.ref.Reference<? extends T>> reference)

Method Detail

get

public T get()

Description copied from interface: Memoize

Get the memoized value.

Specified by:

get in interface Memoize<T>

Specified by:

get in interface java.util.function.Supplier<T>

Returns:

The memoized value.

peek

public T peek()

Description copied from interface: Memoize

Peek the memoized value, if any.

This method will not result in a call to the source supplier.

Specified by:

peek in interface Memoize<T>

Returns:

The memoized value if a value is memoized; otherwise null.

isPresent

public boolean isPresent()

Description copied from interface: Memoize

If a value is memoized, return true. Otherwise return false.

This method will not result in a call to the source supplier.

Specified by:

isPresent in interface Memoize<T>

Returns:

true if a value is memoized; otherwise false.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object