xref: /external/apache-http/src/org/apache/http/impl/conn/tsccm/BasicPoolEntryRef.java

/*
 * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk/module-client/src/main/java/org/apache/http/impl/conn/tsccm/BasicPoolEntryRef.java $
 * $Revision: 674186 $
 * $Date: 2008-07-05 05:18:54 -0700 (Sat, 05 Jul 2008) $
 *
 * ====================================================================
 *
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */

package org.apache.http.impl.conn.tsccm;


import java.lang.ref.WeakReference;
import java.lang.ref.ReferenceQueue;

import org.apache.http.conn.routing.HttpRoute;



/**
 * A weak reference to a {@link BasicPoolEntry BasicPoolEntry}.
 * This reference explicitly keeps the planned route, so the connection
 * can be reclaimed if it is lost to garbage collection.
 */
public class BasicPoolEntryRef extends WeakReference<BasicPoolEntry> {

    /** The planned route of the entry. */
    private final HttpRoute route;


    /**
     * Creates a new reference to a pool entry.
     *
     * @param entry   the pool entry, must not be <code>null</code>
     * @param queue   the reference queue, or <code>null</code>
     */
    public BasicPoolEntryRef(BasicPoolEntry entry,
                             ReferenceQueue<Object> queue) {
        super(entry, queue);
        if (entry == null) {
            throw new IllegalArgumentException
                ("Pool entry must not be null.");
        }
        route = entry.getPlannedRoute();
    }


    /**
     * Obtain the planned route for the referenced entry.
     * The planned route is still available, even if the entry is gone.
     *
     * @return      the planned route
     */
    public final HttpRoute getRoute() {
        return this.route;
    }

} // class BasicPoolEntryRef