Table 1.A: Exceptions

The following table details each of the exception types thrown by AMPS.

Exception	When	Notes
AlreadyConnected	Connecting	Thrown when connect() is called on a Client that is already connected.
AMPS	Anytime	Base class for all AMPS exceptions.
Authentication	Anytime	Indicates an authentication failure occurred on the server.
BadFilter	Subscribing	This typically indicates a syntax error in a filter expression.
BadRegexTopic	Subscribing	Indicates a malformed regular expression was found in the topic name.
Command	Anytime	Base class for all exceptions relating to commands sent to AMPS.
Connection	Anytime	Base class for all exceptions relating to the state of the AMPS connection.
ConnectionRefused	Connecting	The connection was actively refused by the server. Validate that the server is running, that network connectivity is available, and the settings on the client match those on the server.
Disconnected	Anytime	No connection is available when AMPS needed to send data to the server or the user’s disconnect handler threw an exception.
InvalidTopic	Subscribe or Query	The topic is not configured for the requested operation. For example, a sow command was issued for a topic that is not in the SOW or a bookmark subscribe was issued for a topic that is not recorded in the transaction log.
InvalidTransportOptions	Connecting	An invalid option or option value was specified in the URI.
InvalidURI	Connecting	The URI string provided to connect() was formatted improperly.
MessageType	Connecting	The class for a given transport’s message type was not found in AMPS.
MessageTypeNotFound	Connecting	The message type specified in the URI was not found in AMPS.
NameInUse	Connecting	The client name (specified when instantiating Client) is already in use on the server.
RetryOperation	Anytime	An error occurred that caused processing of the last command to be aborted. Try issuing the command again.
Stream	Anytime	Indicates that data corruption has occurred on the connection between the client and server. This usually indicates an internal error inside of AMPS – contact AMPS support.
SubscriptionAlreadyExistsExc eption	Subscribing	A subscription has been requested using the same CommandId as another subscription. Create a unique CommandId for every subscription.
TimedOut	Anytime	A timeout occurred waiting for a response to a command.
TransportType	Connecting	Thrown when a transport type is selected in the URI that is unknown to AMPS.
Unknown	Anytime	Thrown when an internal error occurs. Contact AMPS support immediately.
UsageException	Changing the properties of an object.	Thrown when the object is not in a valid state for setting the properties. For example, some properties of a Client (such as the BookmarkStore used) cannot be changed while that client is connected to AMPS.

Table 1.A: Exceptions supported in Client and HAClient