Data Transformation Engine Services Guide

Chapter 15 – Adapter Functions
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 Get Used to get data from a resource in an input card or GET function. Note
that this same function is called by the adapter to cleanup, or complete, the
operation. Also note this may be called multiple times in burst mode, and that the
sequence of get and cleanup calls depends on the scope settings.
 Put Used to send data to a resource in an output card or PUT function. Note
that this same function is called by the adapter to cleanup, or complete, the
operation. Also note this may be called multiple times in burst mode, and that the
sequence of put and cleanup calls depends on the scope settings.
 Disconnect Used to disconnect from a resource. There is always one
Disconnect call for each Connect call but the call may not always occur within
the context of a map.
 Compare Connections Used to determine whether a connection can be reused.
The input contains pointers to two adapter parameter structures (as returned by
Validate Command) – one for the open connection, and one for the connection
yet to be made. If this function returns TRUE then the Connect call is not called
– the connection is reused instead.
 Free Adapter Parms Used to free up the memory used by the adapter
parameters returned from the Validate Command call.
 Validate Connection Used by the Resource Manager to verify that a
connection is still alive. The adapter should perform some benign action on the
connection that exercises the Validate Connection but does nothing to change its
state. For example, a database adapter could issue a simple select statement while
other adapters execute a “get status” call.
 Shutdown Adapter Used to shutdown the adapter. The adapter can use this
call, which is made only once, to free up memory, destroy critical sections and so
on.
Notes:
If the Initialize Adapter call is successful, then the Shutdown Adapter call is made to
the adapter. Since there is no way for the adapter to return failure or success status on the
Initialize Adapter call, the Shutdown Adapter call is always made.
If the Validate Command call is successful, then the Free Adapter Parms call is made.
If the Connect call is successful, then the DisConnect call is made.