Database integration level – Apple WebObjects 3.5 User Manual
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The Classes in the Request-Response Loop
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WOAssociation (in Java, Association)
Knows how to find and set a value by reference to a key. Instance
variables and action methods of dynamic elements are instances of this
class.
Database Integration Level
Database integration is handled mainly by classes in the Enterprise Objects
Framework (see Figure 18). The Enterprise Objects Framework converts
operations on objects to database operations on records, thereby allowing
your WebObjects application to interact with a database in an object-
oriented manner.
Figure 18. Request-Response Loop: Database Access
Two classes are involved at this level:
•
WODisplayGroup (in Java, DisplayGroup)
Performs fetches, queries, creations, and deletions of records from one
table in the database. WODisplayGroup is a sort of bridge between the
application
adaptor
Request
Response
HTTP server
session store
HTTP server
HTTP server
response
page
request
page
request 1
session 1
WODisplay
Group
EOEditing
Context