org.glassfish.jersey.process.internal.RequestExecutorFactory Maven / Gradle / Ivy
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 2012-2015 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
* http://glassfish.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:
* "Portions Copyright [year] [name of copyright owner]"
*
* Contributor(s):
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package org.glassfish.jersey.process.internal;
import java.util.Iterator;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.glassfish.jersey.internal.LocalizationMessages;
import org.glassfish.jersey.internal.inject.Providers;
import org.glassfish.jersey.internal.util.collection.LazyValue;
import org.glassfish.jersey.internal.util.collection.Value;
import org.glassfish.jersey.internal.util.collection.Values;
import org.glassfish.jersey.spi.RequestExecutorProvider;
import org.glassfish.hk2.api.ServiceLocator;
/**
* {@link org.glassfish.jersey.spi.RequestExecutorProvider Request executors provider} aggregator used by
* client and server-side run-times to provide support for pluggable managed/async executor services.
*
* Instances of {@code RequestExecutorFactory} use the configured request executors provider to
* lazily retrieve and cache an instance of {@link java.util.concurrent.ExecutorService request executor service}
* when {@link #getExecutor()} method is invoked. The retrieved executor service is then cached and returned
* from the {@code getExecutor()} method on subsequent calls.
*
*
* It is expected that the {@code ExecutorFactory}'s {@link #close()} method will be called on any
* executor factory instance that is no longer use. Upon the call to {@code close()} method, the factory
* will release the cached
*
*
* @author Miroslav Fuksa
* @author Marek Potociar (marek.potociar at oracle.com)
*/
public abstract class RequestExecutorFactory {
private static final Logger LOGGER = Logger.getLogger(RequestExecutorFactory.class.getName());
private final RequestExecutorProvider executorProvider;
private final LazyValue executorValue;
private final AtomicBoolean closed = new AtomicBoolean(false);
/**
* Creates new instance.
*
* @param locator Injected HK2 locator.
* @param args additional arguments that will be passed into the
* {@link #getDefaultProvider(Object...)} when/if invoked.
*/
public RequestExecutorFactory(final ServiceLocator locator, Object... args) {
final Iterator providersIterator =
Providers.getAllProviders(locator, RequestExecutorProvider.class).iterator();
if (providersIterator.hasNext()) {
executorProvider = providersIterator.next();
if (LOGGER.isLoggable(Level.CONFIG)) {
LOGGER.config(LocalizationMessages.USING_CUSTOM_REQUEST_EXECUTOR_PROVIDER(
executorProvider.getClass().getName()));
if (providersIterator.hasNext()) {
StringBuilder msg = new StringBuilder(providersIterator.next().getClass().getName());
while (providersIterator.hasNext()) {
msg.append(", ").append(providersIterator.next().getClass().getName());
}
LOGGER.config(LocalizationMessages.IGNORED_CUSTOM_REQUEST_EXECUTOR_PROVIDERS(msg.toString()));
}
}
} else {
executorProvider = getDefaultProvider(args);
if (LOGGER.isLoggable(Level.CONFIG)) {
LOGGER.config(LocalizationMessages.USING_DEFAULT_REQUEST_EXECUTOR_PROVIDER(
executorProvider.getClass().getName()));
}
}
executorValue = Values.lazy(new Value() {
@Override
public ExecutorService get() {
return executorProvider.getRequestingExecutor();
}
});
}
/**
* Get the default request executor provider.
*
* This method is invoked from the {@code RequestExecutorFactory} constructor if no custom
* {@link org.glassfish.jersey.spi.RequestExecutorProvider} registration is found.
* The returned default provider will be then used to provide the default request executor
* implementation.
*
*
* Concrete implementations of this class are expected to provide implementation of this
* method. Note that since the method is used from the {@code RequestExecutorFactory} constructor,
* the implementation of this method must not rely on initialization of any non-static fields
* of the overriding sub-class. Instead, the necessary initialization arguments may be passed
* via super constructor.
*
*
* @param initArgs initialization arguments passed via
* {@link #RequestExecutorFactory(org.glassfish.hk2.api.ServiceLocator, Object...) constructor}
* of this class.
* @return default request executor provider to be used if no custom provider has been registered.
*/
protected abstract RequestExecutorProvider getDefaultProvider(Object... initArgs);
/**
* Get the request processing executor using the underlying {@link RequestExecutorProvider} configured
* in the executor factory instance.
*
* @return request processing executor. Must not return {@code null}.
* @throws java.lang.IllegalStateException in case the factory instance has been {@link #close() closed}
* already.
*/
public final ExecutorService getExecutor() {
if (closed.get()) {
throw new IllegalStateException(LocalizationMessages.REQUEST_EXECUTOR_FACTORY_CLOSED(this.getClass().getName()));
}
return executorValue.get();
}
/**
* Close the executor factory and release any associated executor service resources.
*/
public final void close() {
if (closed.compareAndSet(false, true)) {
if (executorValue.isInitialized()) {
executorProvider.releaseRequestingExecutor(executorValue.get());
}
}
}
}