ComponentProviderService.java
/*
* Copyright (c) 2012, 2017 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package org.glassfish.tyrus.core;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import javax.websocket.Decoder;
import javax.websocket.DeploymentException;
import javax.websocket.Encoder;
import javax.websocket.EndpointConfig;
import javax.websocket.Session;
import org.glassfish.tyrus.core.l10n.LocalizationMessages;
/**
* Provides an instance of component. Searches for registered {@link ComponentProvider}s which are used to provide
* instances.
*
* @author Martin Matula (martin.matula at oracle.com)
* @author Stepan Kopriva (stepan.kopriva at oracle.com)
* @author Pavel Bucek (pavel.bucek at oracle.com)
*/
public class ComponentProviderService {
private final Map<Session, Map<Class<?>, Object>> sessionToObject;
private final List<ComponentProvider> providers;
/**
* Create new instance of {@link ComponentProviderService}.
* <p>
* Searches for registered {@link ComponentProvider}s and registers them with this service.
* <p>
* {@link DefaultComponentProvider} is always added to found providers.
*
* @return initialized {@link ComponentProviderService}.
*/
public static ComponentProviderService create() {
final List<ComponentProvider> foundProviders = new ArrayList<ComponentProvider>();
ServiceFinder<ComponentProvider> finder = ServiceFinder.find(ComponentProvider.class);
for (ComponentProvider componentProvider : finder) {
foundProviders.add(componentProvider);
}
foundProviders.add(new DefaultComponentProvider());
return new ComponentProviderService(Collections.unmodifiableList(foundProviders));
}
/**
* Create new instance of {@link ComponentProviderService}.
* <p>
* Contains *only* {@link DefaultComponentProvider}. Used for creating client instances (CDI/EJB container are
* often confused and using them to retrieve instances leads to unstable results since the injection scope is not
* properly defined for these cases). See https://java.net/jira/browse/WEBSOCKET_SPEC-197 and
* https://java.net/jira/browse/WEBSOCKET_SPEC-196.
*
* @return initialized {@link ComponentProviderService}.
*/
public static ComponentProviderService createClient() {
return new ComponentProviderService(
Collections.unmodifiableList(Arrays.<ComponentProvider>asList(new DefaultComponentProvider())));
}
private ComponentProviderService(List<ComponentProvider> providers) {
this.providers = providers;
this.sessionToObject = new ConcurrentHashMap<Session, Map<Class<?>, Object>>();
}
/**
* Copy constructor.
*
* @param componentProviderService original instance.
*/
public ComponentProviderService(ComponentProviderService componentProviderService) {
this.providers = componentProviderService.providers;
this.sessionToObject = componentProviderService.sessionToObject;
}
/**
* Provide an instance of class which is coupled to {@link Session}.
* <p>
* The first time the method is called the provider creates an instance and caches it.
* Next time the method is called the cached instance is returned.
*
* @param c {@link Class} whose instance will be provided.
* @param session session to which the instance belongs (think of this as a scope).
* @param collector error collector.
* @param <T> type of the provided instance.
* @return instance
*/
public <T> Object getInstance(Class<T> c, Session session, ErrorCollector collector) {
Object loaded = null;
final Map<Class<?>, Object> classObjectMap = sessionToObject.get(session);
try {
if (classObjectMap != null) {
synchronized (classObjectMap) {
if (classObjectMap.containsKey(c)) {
loaded = classObjectMap.get(c);
} else {
// returns not-null value
loaded = getEndpointInstance(c);
sessionToObject.get(session).put(c, loaded);
}
}
} else {
loaded = getEndpointInstance(c);
final HashMap<Class<?>, Object> hashMap = new HashMap<Class<?>, Object>();
hashMap.put(c, loaded);
sessionToObject.put(session, hashMap);
}
} catch (Exception e) {
collector.addException(
new DeploymentException(LocalizationMessages.COMPONENT_PROVIDER_THREW_EXCEPTION(c.getName()), e));
}
return loaded;
}
/**
* Provide an instance of {@link javax.websocket.Encoder} or {@link javax.websocket.Decoder} descendant which is
* coupled to {@link Session}.
* <p>
* The first time the method is called the provider creates an instance, calls {@link
* javax.websocket.Encoder#init(javax.websocket.EndpointConfig)}
* or {@link javax.websocket.Decoder#init(javax.websocket.EndpointConfig)} and caches it.
* Next time the method is called the cached instance is returned.
*
* @param c {@link Class} whose instance will be provided.
* @param session session to which the instance belongs (think of this as a scope).
* @param collector error collector.
* @param endpointConfig configuration corresponding to current context. Used for
* {@link javax.websocket.Encoder#init(javax.websocket.EndpointConfig)} and
* {@link javax.websocket.Decoder#init(javax.websocket.EndpointConfig)}
* @param <T> type of the provided instance.
* @return instance
*/
public <T> Object getCoderInstance(Class<T> c, Session session, EndpointConfig endpointConfig,
ErrorCollector collector) {
Object loaded = null;
final Map<Class<?>, Object> classObjectMap = sessionToObject.get(session);
try {
if (classObjectMap != null) {
synchronized (classObjectMap) {
if (classObjectMap.containsKey(c)) {
loaded = classObjectMap.get(c);
} else {
loaded = getInstance(c);
if (loaded != null) {
if (loaded instanceof Encoder) {
((Encoder) loaded).init(endpointConfig);
} else if (loaded instanceof Decoder) {
((Decoder) loaded).init(endpointConfig);
}
sessionToObject.get(session).put(c, loaded);
}
}
}
} else {
loaded = getInstance(c);
if (loaded != null) {
if (loaded instanceof Encoder) {
((Encoder) loaded).init(endpointConfig);
} else if (loaded instanceof Decoder) {
((Decoder) loaded).init(endpointConfig);
}
final HashMap<Class<?>, Object> hashMap = new HashMap<Class<?>, Object>();
hashMap.put(c, loaded);
sessionToObject.put(session, hashMap);
}
}
} catch (InstantiationException e) {
collector.addException(
new DeploymentException(LocalizationMessages.COMPONENT_PROVIDER_THREW_EXCEPTION(c.getName()), e));
}
return loaded;
}
public Method getInvocableMethod(Method method) {
for (ComponentProvider componentProvider : providers) {
if (componentProvider.isApplicable(method.getDeclaringClass())) {
return componentProvider.getInvocableMethod(method);
}
}
return method;
}
private <T> Object getInstance(Class<T> clazz) throws InstantiationException {
for (ComponentProvider componentProvider : providers) {
if (componentProvider.isApplicable(clazz)) {
final Object t = componentProvider.create(clazz);
if (t != null) {
return t;
}
}
}
throw new InstantiationException(LocalizationMessages.COMPONENT_PROVIDER_NOT_FOUND(clazz.getName()));
}
/**
* Remove {@link Session} from cache.
*
* @param session to be removed.
*/
public void removeSession(Session session) {
final Map<Class<?>, Object> classObjectMap = sessionToObject.get(session);
if (classObjectMap != null) {
synchronized (classObjectMap) {
for (Object o : classObjectMap.values()) {
if (o instanceof Encoder) {
((Encoder) o).destroy();
} else if (o instanceof Decoder) {
((Decoder) o).destroy();
}
for (ComponentProvider componentProvider : providers) {
if (componentProvider.destroy(o)) {
break;
}
}
}
}
}
sessionToObject.remove(session);
}
/**
* This method is called by the container each time a new client
* connects to the logical endpoint this configurator configures.
* Developers may override this method to control instantiation of
* endpoint instances in order to customize the initialization
* of the endpoint instance, or manage them in some other way.
* If the developer overrides this method, services like
* dependency injection that are otherwise supported, for example, when
* the implementation is part of the Java EE platform
* may not be available.
* The platform default implementation of this method returns a new
* endpoint instance per call, thereby ensuring that there is one
* endpoint instance per client, the default deployment cardinality.
*
* @param endpointClass the class of the endpoint.
* @param <T> the type of the endpoint.
* @return an instance of the endpoint that will handle all
* interactions from a new client.
* @throws InstantiationException if there was an error producing the
* endpoint instance.
* @see javax.websocket.server.ServerEndpointConfig.Configurator#getEndpointInstance(Class)
*/
public <T> Object getEndpointInstance(Class<T> endpointClass) throws InstantiationException {
return getInstance(endpointClass);
}
}