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This is the master POM file for Oracle's Implementation of the JSF 2.2 Specification.
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
* If applicable, add the following below the License Header, with the fields
* enclosed by brackets [] replaced by your own identifying information:
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*/
package com.sun.faces.util;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.logging.Logger;
/**
* A concurrent caching mechanism.
*/
public class Cache {
// Log instance for this class
private static final Logger LOGGER = FacesLogger.UTIL.getLogger();
/**
* Factory interface for creating various cacheable objects.
*/
public interface Factory {
V newInstance(final K arg) throws InterruptedException;
} // END Factory
private final ConcurrentMap cache =
new ConcurrentHashMap();
private final Factory factory;
// -------------------------------------------------------- Constructors
/**
* Constructs this cache using the specified Factory.
* @param factory
*/
public Cache(Factory factory) {
this.factory = factory;
}
// ------------------------------------------------------ Public Methods
/**
* If a value isn't associated with the specified key, a new
* {@link java.util.concurrent.Callable} will be created wrapping the Factory
* specified via the constructor and passed to a {@link java.util.concurrent.FutureTask}. This task
* will be passed to the backing ConcurrentMap. When {@link java.util.concurrent.FutureTask#get()}
* is invoked, the Factory will return the new Value which will be cached
* by the {@link java.util.concurrent.FutureTask}.
*
* @param key the key the value is associated with
* @return the value for the specified key, if any
*/
public V get(final K key) {
V result = cache.get(key);
if (result == null)
{
try
{
result = factory.newInstance(key);
}
catch (InterruptedException ie)
{
// will never happen. Just for testing
throw new RuntimeException(ie);
}
// put could be used instead if it didn't matter whether we replaced
// an existing entry
V oldResult = cache.putIfAbsent(key, result);
if (oldResult != null)
result = oldResult;
}
return result;
}
public V remove(final K key) {
return cache.remove(key);
}
} // END Cache