HP NonStop G-Series - Manual (Page 66)

Jolt Class Library Features
The Jolt Class Library has the following characteristics:
Features fully thread-safe classes. ●
Encapsulates typical transaction functions such as logon, synchronous calling, transaction begin, commit, rollback, and logoffs as
Java objects. ●
Contains methods that allow you to set idle time-outs for continuous and intermittent client network connections. ●
Features methods that allow a Jolt client to subscribe to and receive event-based notifications. ●
Jolt Class Library Error and Exception Handling
The Jolt Class Library returns both Jolt interpreter and TUXEDO errors as exceptions. The Jolt Class Library Reference contains the Jolt
classes and lists the errors or exceptions thrown for each class.
Appendix A, Jolt Class Library Errors and Exceptions contains the Error
and Exception Class Reference.
Jolt Client/Server Relationship
Jolt works in a distributed client/server environment and connects Java clients to NonStop TUXEDO based applications. Figure 6-1
illustrates the client/server relationship between a Jolt program and the Jolt Server.
Figure 6-1. Jolt Client/Server Relationship
As illustrated in the diagram, the Jolt Server acts as a proxy for a native NonStop TUXEDO client, implementing functionality available
through the native NonStop TUXEDO client. The Jolt Server accepts requests from Jolt clients and maps those requests into NonStop
TUXEDO service requests through the NonStop TUXEDO ATMI interface. Requests and associated parameters are packaged into a
message buffer and delivered over the network to the Jolt Server. The Jolt Connection Manager handles all communication between the
Jolt Server and the Jolt applet using the Jolt Transaction Protocol. The Jolt Server unpacks the data from the message, performs any
necessary data conversions, such as numeric format conversions or character set conversions, and makes the appropriate service request to
NonStop TUXEDO as specified by the message.
Once a service request enters the NonStop TUXEDO system, it is executed in exactly the same manner as any other NonStop TUXEDO
request. The results are returned through the ATMI interface to the Jolt Server, which packages the results and any error information into a
message that is sent to the Jolt client applet. The Jolt client then maps the contents of the message into the various Jolt client interface
objects, completing the request.
On the client side, the user program contains the client application code. The Jolt Class Library packages a JoltSession and
JoltTransaction, which in turn handle service requests.
The following table describes the client-side requests and Jolt Server-side actions in a simple example program.
Table 6-1. Jolt Client/Server Interaction
Jolt Client Jolt Server
1 attr=new JoltSessionAttributes();
attr.setString( attr.APPADDRESS, "//myhost:8000" ); Binds the
client to the
TUXEDO
environment
2 session=new JoltSession( attr, username, userRole, userPassword, appPassword ); Logs the
client on to
TUXEDO