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package com.sun.javafx.font;

import java.lang.ref.Reference;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.WeakReference;
import java.util.Hashtable;

This class is used for registering and disposing the native data associated with java objects. The object can register itself by calling the addRecord method and providing a descendant of the DisposerRecord class with overridden dispose() method. When the object becomes unreachable, the dispose() method of the associated DisposerRecord object will be called.
See Also:
  • DisposerRecord
/** * This class is used for registering and disposing the native * data associated with java objects. * * The object can register itself by calling the addRecord method and * providing a descendant of the DisposerRecord class with overridden * dispose() method. * * When the object becomes unreachable, the dispose() method * of the associated DisposerRecord object will be called. * * @see DisposerRecord */
public class Disposer implements Runnable { private static final ReferenceQueue queue = new ReferenceQueue(); private static final Hashtable records = new Hashtable(); private static Disposer disposerInstance; static { disposerInstance = new Disposer(); ThreadGroup tg = Thread.currentThread().getThreadGroup(); java.security.AccessController.doPrivileged( new java.security.PrivilegedAction() { public Object run() { /* The thread must be a member of a thread group * which will not get GCed before VM exit. * Make its parent the top-level thread group. */ ThreadGroup tg = Thread.currentThread().getThreadGroup(); for (ThreadGroup tgn = tg; tgn != null; tg = tgn, tgn = tg.getParent()); Thread t = new Thread(tg, disposerInstance, "Prism Font Disposer"); t.setContextClassLoader(null); t.setDaemon(true); t.setPriority(Thread.MAX_PRIORITY); t.start(); return null; } } ); }
Registers the object and the native data for later disposal.
Params:
  • target – Object to be registered
  • rec – the associated DisposerRecord object
See Also:
/** * Registers the object and the native data for later disposal. * @param target Object to be registered * @param rec the associated DisposerRecord object * @see DisposerRecord */
public static WeakReference addRecord(Object target, DisposerRecord rec) { WeakReference ref = new WeakReference(target, queue); disposerInstance.records.put(ref, rec); return ref; } public void run() { while (true) { try { Object obj = queue.remove(); ((Reference)obj).clear(); DisposerRecord rec = (DisposerRecord)records.remove(obj); rec.dispose(); obj = null; rec = null; } catch (Exception e) { System.out.println("Exception while removing reference: " + e); e.printStackTrace(); } } } }