RowSet object calls on
* to populate itself with rows of data. A reader (an object implementing the
* RowSetReader interface) may be registered with
* a RowSet object that supports the reader/writer paradigm.
* When the RowSet object's execute method is
* called, it in turn calls the reader's readData method.
*
* @since 1.4
*/
public interface RowSetReader {
/**
* Reads the new contents of the calling RowSet object.
* In order to call this method, a RowSet
* object must have implemented the RowSetInternal interface
* and registered this RowSetReader object as its reader.
* The readData method is invoked internally
* by the RowSet.execute method for rowsets that support the
* reader/writer paradigm.
*
* The readData method adds rows to the caller.
* It can be implemented in a wide variety of ways and can even
* populate the caller with rows from a nonrelational data source.
* In general, a reader may invoke any of the rowset's methods,
* with one exception. Calling the method execute will
* cause an SQLException to be thrown
* because execute may not be called recursively. Also,
* when a reader invokes RowSet methods, no listeners
* are notified; that is, no RowSetEvent objects are
* generated and no RowSetListener methods are invoked.
* This is true because listeners are already being notified by the method
* execute.
*
* @param caller the RowSet object (1) that has implemented the
* RowSetInternal interface, (2) with which this reader is
* registered, and (3) whose execute method called this reader
* @exception SQLException if a database access error occurs or this method
* invokes the RowSet.execute method
*/
void readData(RowSetInternal caller) throws SQLException;
}