| Interface | Description | 
|---|---|
| DataRow | 
 This interface is used to marshal row content between client
 and middle tier. 
 | 
| Request | 
 This interface is used to marshal a service message request between client
 and middle tier. 
 | 
| RequestParams | 
 This interface extends  
Request and adds ability
 to marshal various data values with it. | 
| Response | 
 This interface is used to marshal a service message response from the middle tier
 to the client tier. 
 | 
| ResponseEvent | 
 This interface extends  
Response. | 
| ResponseRef | 
 This interface extends  
ResponseValues. | 
| ResponseRowEvent | 
 This interface extends  
Response. | 
| ResponseValues | 
 This interface extends  
Response and adds ability
 to marshal various data values with it. | 
| SvcMsgReceiver | 
 This interface is implemented by classes that receive
 service messages. 
 | 
| SvcMsgSender | 
 This interface is implemented by classes that send
 service messages. 
 | 
| Class | Description | 
|---|---|
| ServiceMessage | 
 This class carries service message that contains
 either requests from  
SvcMsgSender to
 SvcMsgReceiver, or returning responses from
 SvcMsgReceiver to SvcMsgSender. | 
| Exception | Description | 
|---|---|
| ServiceException | 
ServiceException is an exception which indicates
 an error during service message processing. |