/*
 * (C) Copyright 2014 Kurento (http://kurento.org/)
 *
 * 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.kurento.tutorial.groupcall;

import java.util.concurrent.ConcurrentHashMap;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.socket.WebSocketSession;

/**
 * Map of users registered in the system. This class has a concurrent hash map to store users, using
 * its name as key in the map.
 * 
 * @author Boni Garcia (bgarcia@gsyc.es)
 * @author Micael Gallego (micael.gallego@gmail.com)
 * @authos Ivan Gracia (izanmail@gmail.com)
 * @since 4.3.1
 */
public class UserRegistry {

  private final ConcurrentHashMap<String, UserSession> usersByName = new ConcurrentHashMap<>();
  private final ConcurrentHashMap<String, UserSession> usersBySessionId = new ConcurrentHashMap<>();

  private static final Logger log = LoggerFactory.getLogger(CallHandler.class);

  public void register(UserSession user) {
    usersByName.put(user.getName(), user);
    log.info("added user: {}", user.getName());
    usersBySessionId.put(user.getSession().getId(), user);
  }

  public UserSession getByName(String name) {
    return usersByName.get(name);
  }

  public UserSession getBySession(WebSocketSession session) {
    return usersBySessionId.get(session.getId());
  }

  public boolean exists(String name) {
    return usersByName.keySet().contains(name);
  }

  public UserSession removeBySession(WebSocketSession session) {
    if (session != null) {
      final UserSession user = getBySession(session);
      log.info("removed user: {}", user.getName());
      usersByName.remove(user.getName());
      usersBySessionId.remove(session.getId());
      return user;
    }
    return null;
  }
}

@@ -2059,16 +2059,44 @@
 ssion);%0A
+      if (user != null) %7B%0A  
       lo
@@ -2141,24 +2141,26 @@
 e());%0A      
+  
 usersByName.
@@ -2185,24 +2185,26 @@
 e());%0A      
+ 
+ 
 usersBySessi
@@ -2235,24 +2235,26 @@
 d());%0A      
+  
 return user;
@@ -2254,16 +2254,43 @@
 n user;%0A
+      %7D%0A      return null;%0A
     %7D%0A  

add another null check