/*
* Copyright (c) 2010-2014 Sonatype, Inc. All rights reserved.
*
* This program is licensed to you under the Apache License Version 2.0,
* and you may not use this file except in compliance with the Apache License Version 2.0.
* You may obtain a copy of the Apache License Version 2.0 at http://www.apache.org/licenses/LICENSE-2.0.
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the Apache License Version 2.0 is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the Apache License Version 2.0 for the specific language governing permissions and limitations there under.
*/
package org.asynchttpclient.extras.registry;
import org.asynchttpclient.AsyncHttpClient;
import org.asynchttpclient.AsyncHttpClientConfig;
import org.asynchttpclient.AsyncHttpProvider;
import org.asynchttpclient.DefaultAsyncHttpClient;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.lang.reflect.Constructor;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
/**
* The AsyncHttpClientFactory returns back an instance of AsyncHttpClient. The
* actual instance is determined by the system property
* 'org.async.http.client.impl'. If the system property doesn't exist then it
* checks for a property file 'asynchttpclient.properties' and looks for a
* property 'org.async.http.client.impl' in there. If it finds it then returns
* an instance of that class. If there is an exception while reading the
* properties file or system property it throws a RuntimeException
* AsyncHttpClientImplException. If any of the constructors of the instance
* throws an exception it thows a AsyncHttpClientImplException. By default if
* neither the system property or the property file exists then it will return
* the default instance of {@link DefaultAsyncHttpClient}
*
* @author sasurendran
*
*/
public class AsyncHttpClientFactory {
private static Class<AsyncHttpClient> asyncHttpClientImplClass = null;
private static volatile boolean instantiated = false;
public static final Logger logger = LoggerFactory.getLogger(AsyncHttpClientFactory.class);
private static Lock lock = new ReentrantLock();
public static AsyncHttpClient getAsyncHttpClient() {
try {
if (attemptInstantiation())
return (AsyncHttpClient) asyncHttpClientImplClass.newInstance();
} catch (InstantiationException e) {
throw new AsyncHttpClientImplException("Unable to create the class specified by system property : "
+ AsyncImplHelper.ASYNC_HTTP_CLIENT_IMPL_SYSTEM_PROPERTY, e);
} catch (IllegalAccessException e) {
throw new AsyncHttpClientImplException("Unable to find the class specified by system property : "
+ AsyncImplHelper.ASYNC_HTTP_CLIENT_IMPL_SYSTEM_PROPERTY, e);
}
return new DefaultAsyncHttpClient();
}
public static AsyncHttpClient getAsyncHttpClient(AsyncHttpProvider provider) {
if (attemptInstantiation()) {
try {
Constructor<AsyncHttpClient> constructor = asyncHttpClientImplClass.getConstructor(AsyncHttpProvider.class);
return constructor.newInstance(provider);
} catch (Exception e) {
throw new AsyncHttpClientImplException("Unable to find the instantiate the class specified by system property : "
+ AsyncImplHelper.ASYNC_HTTP_CLIENT_IMPL_SYSTEM_PROPERTY + "(AsyncHttpProvider) due to : " + e.getMessage(), e);
}
}
return new DefaultAsyncHttpClient(provider);
}
public static AsyncHttpClient getAsyncHttpClient(AsyncHttpClientConfig config) {
if (attemptInstantiation()) {
try {
Constructor<AsyncHttpClient> constructor = asyncHttpClientImplClass.getConstructor(AsyncHttpClientConfig.class);
return constructor.newInstance(config);
} catch (Exception e) {
throw new AsyncHttpClientImplException("Unable to find the instantiate the class specified by system property : "
+ AsyncImplHelper.ASYNC_HTTP_CLIENT_IMPL_SYSTEM_PROPERTY + "(AsyncHttpProvider) due to : " + e.getMessage(), e);
}
}
return new DefaultAsyncHttpClient(config);
}
public static AsyncHttpClient getAsyncHttpClient(AsyncHttpProvider provider, AsyncHttpClientConfig config) {
if (attemptInstantiation()) {
try {
Constructor<AsyncHttpClient> constructor = asyncHttpClientImplClass.getConstructor(AsyncHttpProvider.class,
AsyncHttpClientConfig.class);
return constructor.newInstance(provider, config);
} catch (Exception e) {
throw new AsyncHttpClientImplException("Unable to find the instantiate the class specified by system property : "
+ AsyncImplHelper.ASYNC_HTTP_CLIENT_IMPL_SYSTEM_PROPERTY + "(AsyncHttpProvider) due to : " + e.getMessage(), e);
}
}
return new DefaultAsyncHttpClient(provider, config);
}
public static AsyncHttpClient getAsyncHttpClient(String providerClass, AsyncHttpClientConfig config) {
if (attemptInstantiation()) {
try {
Constructor<AsyncHttpClient> constructor = asyncHttpClientImplClass.getConstructor(String.class,
AsyncHttpClientConfig.class);
return constructor.newInstance(providerClass, config);
} catch (Exception e) {
throw new AsyncHttpClientImplException("Unable to find the instantiate the class specified by system property : "
+ AsyncImplHelper.ASYNC_HTTP_CLIENT_IMPL_SYSTEM_PROPERTY + "(AsyncHttpProvider) due to : " + e.getMessage(), e);
}
}
return new DefaultAsyncHttpClient(providerClass, config);
}
private static boolean attemptInstantiation() {
if (!instantiated) {
lock.lock();
try {
if (!instantiated) {
asyncHttpClientImplClass = AsyncImplHelper.getAsyncImplClass(AsyncImplHelper.ASYNC_HTTP_CLIENT_IMPL_SYSTEM_PROPERTY);
instantiated = true;
}
} finally {
lock.unlock();
}
}
return asyncHttpClientImplClass != null;
}
}