Refreshing Single Row Without Full Rollback

With ADF Rollback operation - ADF is reloading entire dataset from DB. It invokes ROLLBACK from database and then executes View Object to return latest data from DB for all rows. This works well when we want to undo multiple changes at once. It may happen to encounter such use case, where we need to undo changes per row, not per set of rows. This is possible in ADF as well - using refresh(...) method for ADF BC Row. But keep in mind, while this method refreshes selected row - it never cleans up ADF BC transaction, it will remain dirty. This is logical - ADF BC doesn't know, if there are other changed rows. This means - you should provide to the user both buttons:

1. Undo - will rollback changes for all rows and mark transaction clean (standard Rollback operation)
2. Undo Row - will refresh only selected row and keep transaction dirty (Described in this post)

In this post I will describe how to refresh selected row, download sample application - RowHighlight_v2.zip. This application is extended version of my previous sample from this post - Changed Row Highlighting in Oracle ADF Table.

We will see first, how ADF BC performs when executing standard Rollback operation. There are three rows changed, row selection is on last row:

Press Undo to invoke Rollback operation, when operation is completed - changes are cleared from all rows as expected, but there is side effect - row selection is lost and reset to point to the first row:

If we check in the log, there is plain SQL statement executed for entire data collection - without bind variable restriction, this re-executes View Object:

Will demo now, how single row refresh works. User needs to select row, where changes should be cleared:

Press Undo Row button - changes for the selected row will be cleared, without affecting existing changes for other rows. Its very important - row selection will stay on the same row as it was before invoking Undo Row operation:

Now we can see different picture in the log - ADF BC executes SQL restricted by bind variable and fetches only data for specific row we are refreshing. This will perform much better comparing to standard Rollback operation:

Single row refresh is implemented as custom method inside View Object implementation class. For current row we are calling refresh operation with REFRESH_UNDO_CHANGES and REFRESH_WITH_DB_FORGET_CHANGES arguments - this will force to reload current row cache:

This method is exposed through View Object client interface and is accesible from Data Control:

Method is declared in Page Definition:

Is invoked from Managed Bean action method: