Class Finalizer

  • All Implemented Interfaces:
    Runnable

    public class Finalizer
    extends Object
    implements 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 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.

    • 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
      • start

        public void start()
      • run

        public void run()
        Loops continuously, pulling references off the queue and cleaning them up.
        Specified by:
        run in interface Runnable
      • getInheritableThreadLocalsField

        public static Field getInheritableThreadLocalsField()
      • getInheritableThreadLocalsConstructor

        public static Constructor<Thread> getInheritableThreadLocalsConstructor()