package org.jboss.seam.remoting.messaging;
import static org.jboss.seam.annotations.Install.BUILT_IN;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.UUID;
import javax.jms.ExceptionListener;
import javax.jms.JMSException;
import javax.jms.TopicConnection;
import org.jboss.seam.Component;
import org.jboss.seam.ScopeType;
import org.jboss.seam.annotations.Install;
import org.jboss.seam.annotations.Name;
import org.jboss.seam.annotations.Scope;
import org.jboss.seam.annotations.intercept.BypassInterceptors;
import org.jboss.seam.contexts.Context;
import org.jboss.seam.contexts.Contexts;
import org.jboss.seam.log.LogProvider;
import org.jboss.seam.log.Logging;
/**
*
* @author Shane Bryzak
*/
@Scope(ScopeType.APPLICATION)
@BypassInterceptors
@Name("org.jboss.seam.remoting.messaging.subscriptionRegistry")
@Install(value = false, precedence=BUILT_IN)
public class SubscriptionRegistry
{
public static final String CONTEXT_USER_TOKENS =
"org.jboss.seam.remoting.messaging.SubscriptionRegistry.userTokens";
private static final LogProvider log = Logging.getLogProvider(SubscriptionRegistry.class);
private String connectionProvider;
private volatile TopicConnection topicConnection;
private Object monitor = new Object();
private Map<String,RemoteSubscriber> subscriptions = new HashMap<String,RemoteSubscriber>();
/**
* Contains a list of all the topics that clients are allowed to subscribe to.
*/
private Set<String> allowedTopics = new HashSet<String>();
public static SubscriptionRegistry instance()
{
SubscriptionRegistry registry = (SubscriptionRegistry) Component.getInstance(SubscriptionRegistry.class);
if (registry == null)
{
throw new IllegalStateException("No SubscriptionRegistry exists");
}
return registry;
}
public Set<String> getAllowedTopics()
{
return allowedTopics;
}
public void setAllowedTopics(Set<String> allowedTopics)
{
this.allowedTopics = allowedTopics;
}
public String getConnectionProvider()
{
return connectionProvider;
}
public void setConnectionProvider(String connectionProvider)
{
this.connectionProvider = connectionProvider;
}
private TopicConnection getTopicConnection()
throws Exception
{
if (topicConnection == null)
{
synchronized(monitor)
{
if (topicConnection == null)
{
topicConnection = org.jboss.seam.jms.TopicConnection.instance();
topicConnection.setExceptionListener(new ExceptionListener() {
public void onException(JMSException ex)
{
// swallow the exception for now - do we need to try and reconnect???
}
});
topicConnection.start();
}
}
}
return topicConnection;
}
public RemoteSubscriber subscribe(String topicName)
{
if (!allowedTopics.contains(topicName))
throw new IllegalArgumentException(String.format(
"Cannot subscribe to a topic that is not allowed. Topic [%s] is not an " +
"allowed topic.", topicName));
RemoteSubscriber sub = new RemoteSubscriber(UUID.randomUUID().toString(), topicName);
try {
sub.subscribe(getTopicConnection());
subscriptions.put(sub.getToken(), sub);
// Save the client's token in their session context
getUserTokens().add(sub.getToken());
return sub;
}
catch (Exception ex) {
log.error(ex);
return null;
}
}
/**
*
* @return Set
*/
public Set getUserTokens()
{
Context session = Contexts.getSessionContext();
if (session.get(CONTEXT_USER_TOKENS) == null)
{
synchronized(session)
{
if (session.get(CONTEXT_USER_TOKENS) == null)
session.set(CONTEXT_USER_TOKENS, new HashSet<String> ());
}
}
return (Set) session.get(CONTEXT_USER_TOKENS);
}
public RemoteSubscriber getSubscription(String token)
{
if (!getUserTokens().contains(token))
throw new IllegalArgumentException(
"Invalid token argument - token not found in Session Context.");
return subscriptions.get(token);
}
}