| // Copyright 2007 The Apache Software Foundation |
| // |
| // Licensed 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. |
| |
| package org.apache.tapestry.ioc.internal; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import java.lang.ref.WeakReference; |
| |
| /** |
| * Serialization support for service proxies. |
| */ |
| class SerializationSupport |
| { |
| private static final Logger LOGGER = LoggerFactory.getLogger(SerializationSupport.class); |
| |
| // We use a weak reference so that the underlying Registry can be reclaimed by the garbage collector |
| // even if it is not explicitly shut down. |
| |
| private static WeakReference<ServiceProxyProvider> providerRef; |
| |
| static synchronized void setProvider(ServiceProxyProvider proxyProvider) |
| { |
| ServiceProxyProvider existing = currentProvider(); |
| |
| if (existing != null) LOGGER.error(IOCMessages.overlappingServiceProxyProviders()); |
| |
| providerRef = new WeakReference<ServiceProxyProvider>(proxyProvider); |
| } |
| |
| private static ServiceProxyProvider currentProvider() |
| { |
| return providerRef == null ? null : providerRef.get(); |
| } |
| |
| static synchronized void clearProvider(ServiceProxyProvider proxyProvider) |
| { |
| ServiceProxyProvider existing = currentProvider(); |
| |
| // The registry does a setProvider() at startup, and we want to make sure that we're the only Registry, that |
| // there hasn't been another setProvider() by another Registry. |
| |
| if (existing != proxyProvider) |
| { |
| LOGGER.error(IOCMessages.unexpectedServiceProxyProvider()); |
| return; |
| } |
| |
| // Good. It's all the expected simple case, without duelling registries. Kill the reference |
| // to the registry. |
| |
| providerRef = null; |
| } |
| |
| static synchronized Object readResolve(String serviceId) |
| { |
| ServiceProxyProvider provider = currentProvider(); |
| |
| if (provider == null) throw new RuntimeException(IOCMessages.noProxyProvider(serviceId)); |
| |
| return provider.provideServiceProxy(serviceId); |
| } |
| |
| static ServiceProxyToken createToken(String serviceId) |
| { |
| return new ServiceProxyToken(serviceId); |
| } |
| |
| } |