Package com.google.common.base.internal

Class Finalizer

java.lang.Object

com.google.common.base.internal.Finalizer

All Implemented Interfaces:

java.lang.Runnable

public class Finalizer
extends java.lang.Object
implements java.lang.Runnable

Thread that finalizes referents. All references should implement com.google.common.base.FinalizableReference.

While this class is public, we consider it to be *internal* and not part of our published API. It is public so we can access it reflectively across class loaders in secure environments.

This class can't depend on other Guava code. If we were to load this class in the same class loader as the rest of Guava, this thread would keep an indirect strong reference to the class loader and prevent it from being garbage collected. This poses a problem for environments where you want to throw away the class loader. For example, dynamically reloading a web application or unloading an OSGi bundle.

com.google.common.base.FinalizableReferenceQueue loads this class in its own class loader. That way, this class doesn't prevent the main class loader from getting garbage collected, and this class can detect when the main class loader has been garbage collected and stop itself.

Method Summary

Modifier and Type	Method	Description
static java.lang.reflect.Field	getInheritableThreadLocalsField()
void	run()	Loops continuously, pulling references off the queue and cleaning them up.
static void	startFinalizer(java.lang.Class<?> finalizableReferenceClass, java.lang.ref.ReferenceQueue<java.lang.Object> queue, java.lang.ref.PhantomReference<java.lang.Object> frqReference)	Starts the Finalizer thread.

Methods inherited from class java.lang.Object

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

Method Detail

startFinalizer

public static void startFinalizer(java.lang.Class<?> finalizableReferenceClass,
                                  java.lang.ref.ReferenceQueue<java.lang.Object> queue,
                                  java.lang.ref.PhantomReference<java.lang.Object> frqReference)

Starts the Finalizer thread. FinalizableReferenceQueue calls this method reflectively.

Parameters:

finalizableReferenceClass - FinalizableReference.class.

queue - a reference queue that the thread will poll.

frqReference - a phantom reference to the FinalizableReferenceQueue, which will be queued either when the FinalizableReferenceQueue is no longer referenced anywhere, or when its close() method is called.

run

public void run()

Loops continuously, pulling references off the queue and cleaning them up.

Specified by:

run in interface java.lang.Runnable

getInheritableThreadLocalsField

@Nullable
public static java.lang.reflect.Field getInheritableThreadLocalsField()