Interface FilteredRowSet

A JDBC FilteredRowSet standard implementation implements the RowSet interfaces and extends the CachedRowSet^TM class. The CachedRowSet class provides a set of protected cursor manipulation methods, which a FilteredRowSet implementation can override to supply filtering support. 2.0 Predicate Sharing If a FilteredRowSet implementation is shared using the inherited createShared method in parent interfaces, the Predicate should be shared without modification by all FilteredRowSet instance clones. 3.0 Usage

By implementing a Predicate (see example in Predicate class JavaDoc), a FilteredRowSet could then be used as described below.

     FilteredRowSet frs = new FilteredRowSetImpl();
     frs.populate(rs);

     Range name = new Range("Alpha", "Bravo", "columnName");
     frs.setFilter(name);

     frs.next() // only names from "Alpha" to "Bravo" will be returned
 

This framework allows multiple classes implementing predicates to be used in combination to achieved the required filtering result with out the need for query language processing.

4.0 Updating a FilteredRowSet Object The predicate set on a FilteredRowSet object applies a criterion on all rows in a RowSet object to manage a subset of rows in a RowSet object. This criterion governs the subset of rows that are visible and also defines which rows can be modified, deleted or inserted.

Therefore, the predicate set on a FilteredRowSet object must be considered as bi-directional and the set criterion as the gating mechanism for all views and updates to the FilteredRowSet object. Any attempt to update the FilteredRowSet that violates the criterion will result in a SQLException object being thrown.

The FilteredRowSet range criterion can be modified by applying a new Predicate object to the FilteredRowSet instance at any time. This is possible if no additional references to the FilteredRowSet object are detected. A new filter has has an immediate effect on criterion enforcement within the FilteredRowSet object, and all subsequent views and updates will be subject to similar enforcement.

5.0 Behavior of Rows Outside the Filter Rows that fall outside of the filter set on a FilteredRowSet object cannot be modified until the filter is removed or a new filter is applied.

Furthermore, only rows that fall within the bounds of a filter will be synchronized with the data source.