uk.ac.starlink.util

Class Cleaner

java.lang.Object

uk.ac.starlink.util.Cleaner

public class Cleaner
extends Object

Manages a set of object references and corresponding cleaning actions. It is used to manage end-of-life actions for an object, in particular to replace use of finalizers, which at Java 21 are deprecated for removal (and which are generally frowned upon).

This is a more-or-less drop-in replacement for the java.lang.ref.Cleaner class introduced in Java 9. If the target platform for this package gets upgraded to Java 9 or greater, this class can be retired in favour of the JRE implementation.

The getInstance() method lazily constructs a singleton instance, which is probably suitable for most purposes. But you can construct your own if you want.

Since:

25 Jul 2024

Author:

Mark Taylor

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	Cleaner.Cleanable Cleanable represents an object and a cleaning action registered in a Cleaner.

Constructor Summary

Constructors

Constructor and Description
Cleaner() Constructor.

Method Summary

Modifier and Type	Method and Description
static Cleaner	getInstance() Returns a lazily constructed singleton instance of this class.
Cleaner.Cleanable	register(Object obj, Runnable action) Registers an object and a cleaning action to run when the object becomes phantom reachable.

Methods inherited from class java.lang.Object

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

Constructor Detail

Cleaner

public Cleaner()

Constructor.

Method Detail

register

public Cleaner.Cleanable register(Object obj,
                                  Runnable action)

Registers an object and a cleaning action to run when the object becomes phantom reachable.

Parameters:

obj - the object to monitor

action - a Runnable to invoke when the object becomes phantom reachable

Returns:

a Cleanable instance

getInstance

public static Cleaner getInstance()

Returns a lazily constructed singleton instance of this class.

Returns:

singleton instance