/*
* Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package com.sun.jndi.ldap.pool;
import java.lang.ref.WeakReference;
import java.lang.ref.ReferenceQueue;
/*
* This class defines a WeakReference to the ConnectionRef (the referent).
*
* The ConnectionRef enables to break the reference
* cycle between Connection, LdapClient, Connections and ConnectionDesc,
* shown in the figure below.
*
* -------> Connections -----> ConnectionDesc
* | ^ |
* | | |
* | | |
* ConnectionsRef LdapClient <------------
* ^ | ^
* : | |
* : v |
* ConnectionsWeakRef Connection
*
* The ConnectionsRef is for cleaning up the resources held by the
* Connection thread by making them available to the GC. The pool
* uses ConnectionRef to hold the pooled resources.
*
* This class in turn holds a WeakReference with a ReferenceQueue to the
* ConnectionRef to track when the ConnectionRef becomes ready
* for getting GC'ed. It extends from WeakReference in order to hold a
* reference to Connections used for closing (which in turn terminates
* the Connection thread) it by monitoring the ReferenceQueue.
*/
class ConnectionsWeakRef extends WeakReference {
private final Connections conns;
ConnectionsWeakRef (ConnectionsRef connsRef, ReferenceQueue queue) {
super(connsRef, queue);
this.conns = connsRef.getConnections();
}
Connections getConnections() {
return conns;
}
}