code: public Object getSessionAttribute(String key, Object defaultValue)
      {
          Object attributeValue = this.sessionAttributes.get(key);
          if (attributeValue == null)
              attributeValue = defaultValue;
          return attributeValue;
      }
docs: Get a value from the session attributes map.
  
  @param key a unique string code
  @param defaultValue the default value if not found
  @return The session attibute or the default value if not found