com.google.common.base.internal
Class Finalizer

java.lang.Object
  java.lang.Thread
      com.google.common.base.internal.Finalizer

All Implemented Interfaces:

Runnable

public class Finalizer
extends Thread

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 Google Collections code. If we were to load this class in the same class loader as the rest of Google Collections, 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.

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

Thread.State, Thread.UncaughtExceptionHandler

Field Summary

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Method Summary

static Field	getInheritableThreadLocalsField()
void	run() Loops continuously, pulling references off the queue and cleaning them up.
static ReferenceQueue<Object>	startFinalizer(Class<?> finalizableReferenceClass, Object frq) Starts the Finalizer thread.

Methods inherited from class java.lang.Thread

activeCount, checkAccess, clone, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, googleGetContext0, googleSetContext0, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Method Detail

startFinalizer

public static ReferenceQueue<Object> startFinalizer(Class<?> finalizableReferenceClass,
                                                    Object frq)

Starts the Finalizer thread. FinalizableReferenceQueue calls this method reflectively.

Parameters:

finalizableReferenceClass - FinalizableReference.class

frq - reference to instance of FinalizableReferenceQueue that started this thread

Returns:

ReferenceQueue which Finalizer will poll

run

public void run()

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

Specified by:

run in interface Runnable

Overrides:

run in class Thread

getInheritableThreadLocalsField

public static Field getInheritableThreadLocalsField()