API java : FilteredRowSet

javax.sql.rowset
Interface FilteredRowSet

All Superinterfaces:

CachedRowSet, Joinable, ResultSet, RowSet, WebRowSet

public interface FilteredRowSet
extends WebRowSet

The standard interface that all standard implementations of FilteredRowSet must implement. The FilteredRowSetImpl class provides the reference implementation which may be extended if required. Alternatively, a vendor is free to implement its own version by implementing this interface.

1.0 Background

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

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

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

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

Field Summary

 

Fields inherited from interface javax.sql.rowset.WebRowSet
PUBLIC_XML_SCHEMA, SCHEMA_SYSTEM_ID

 

Fields inherited from interface javax.sql.rowset.CachedRowSet
COMMIT_ON_ACCEPT_CHANGES

 

Fields inherited from interface java.sql.ResultSet
CLOSE_CURSORS_AT_COMMIT, CONCUR_READ_ONLY, CONCUR_UPDATABLE, FETCH_FORWARD, FETCH_REVERSE, FETCH_UNKNOWN, HOLD_CURSORS_OVER_COMMIT, TYPE_FORWARD_ONLY, TYPE_SCROLL_INSENSITIVE, TYPE_SCROLL_SENSITIVE

 

Method Summary
Predicate	getFilter()           Retrieves the active filter for this FilteredRowSet object.
void	setFilter(Predicate p)           Applies the given Predicate object to this FilteredRowSet object.

 

Methods inherited from interface javax.sql.rowset.WebRowSet
readXml, readXml, writeXml, writeXml, writeXml, writeXml

 

Methods inherited from interface javax.sql.rowset.CachedRowSet

acceptChanges, acceptChanges, columnUpdated, columnUpdated, commit, createCopy, createCopyNoConstraints, createCopySchema, createShared, execute, getKeyColumns, getOriginal, getOriginalRow, getPageSize, getRowSetWarnings, getShowDeleted, getSyncProvider, getTableName, nextPage, populate, populate, previousPage, release, restoreOriginal, rollback, rollback, rowSetPopulated, setKeyColumns, setMetaData, setOriginalRow, setPageSize, setShowDeleted, setSyncProvider, setTableName, size, toCollection, toCollection, toCollection, undoDelete, undoInsert, undoUpdate

 

Methods inherited from interface javax.sql.RowSet

addRowSetListener, clearParameters, execute, getCommand, getDataSourceName, getEscapeProcessing, getMaxFieldSize, getMaxRows, getPassword, getQueryTimeout, getTransactionIsolation, getTypeMap, getUrl, getUsername, isReadOnly, removeRowSetListener, setArray, setAsciiStream, setBigDecimal, setBinaryStream, setBlob, setBoolean, setByte, setBytes, setCharacterStream, setClob, setCommand, setConcurrency, setDataSourceName, setDate, setDate, setDouble, setEscapeProcessing, setFloat, setInt, setLong, setMaxFieldSize, setMaxRows, setNull, setNull, setObject, setObject, setObject, setPassword, setQueryTimeout, setReadOnly, setRef, setShort, setString, setTime, setTime, setTimestamp, setTimestamp, setTransactionIsolation, setType, setTypeMap, setUrl, setUsername

 

Methods inherited from interface java.sql.ResultSet

absolute, afterLast, beforeFirst, cancelRowUpdates, clearWarnings, close, deleteRow, findColumn, first, getArray, getArray, getAsciiStream, getAsciiStream, getBigDecimal, getBigDecimal, getBigDecimal, getBigDecimal, getBinaryStream, getBinaryStream, getBlob, getBlob, getBoolean, getBoolean, getByte, getByte, getBytes, getBytes, getCharacterStream, getCharacterStream, getClob, getClob, getConcurrency, getCursorName, getDate, getDate, getDate, getDate, getDouble, getDouble, getFetchDirection, getFetchSize, getFloat, getFloat, getInt, getInt, getLong, getLong, getMetaData, getObject, getObject, getObject, getObject, getRef, getRef, getRow, getShort, getShort, getStatement, getString, getString, getTime, getTime, getTime, getTime, getTimestamp, getTimestamp, getTimestamp, getTimestamp, getType, getUnicodeStream, getUnicodeStream, getURL, getURL, getWarnings, insertRow, isAfterLast, isBeforeFirst, isFirst, isLast, last, moveToCurrentRow, moveToInsertRow, next, previous, refreshRow, relative, rowDeleted, rowInserted, rowUpdated, setFetchDirection, setFetchSize, updateArray, updateArray, updateAsciiStream, updateAsciiStream, updateBigDecimal, updateBigDecimal, updateBinaryStream, updateBinaryStream, updateBlob, updateBlob, updateBoolean, updateBoolean, updateByte, updateByte, updateBytes, updateBytes, updateCharacterStream, updateCharacterStream, updateClob, updateClob, updateDate, updateDate, updateDouble, updateDouble, updateFloat, updateFloat, updateInt, updateInt, updateLong, updateLong, updateNull, updateNull, updateObject, updateObject, updateObject, updateObject, updateRef, updateRef, updateRow, updateShort, updateShort, updateString, updateString, updateTime, updateTime, updateTimestamp, updateTimestamp, wasNull

 

Methods inherited from interface javax.sql.rowset.Joinable
getMatchColumnIndexes, getMatchColumnNames, setMatchColumn, setMatchColumn, setMatchColumn, setMatchColumn, unsetMatchColumn, unsetMatchColumn, unsetMatchColumn, unsetMatchColumn

 

Method Detail

setFilter

void setFilter(Predicate p)
               throws SQLException

Applies the given Predicate object to this FilteredRowSet object. The filter applies controls both to inbound and outbound views, constraining which rows are visible and which rows can be manipulated.

A new Predicate object may be set at any time. This has the effect of changing constraints on the RowSet object's data. In addition, modifying the filter at runtime presents issues whereby multiple components may be operating on one FilteredRowSet object. Application developers must take responsibility for managing multiple handles to FilteredRowSet objects when their underling Predicate objects change.

Parameters:

p - a Predicate object defining the filter for this FilteredRowSet object. Setting a null value will clear the predicate, allowing all rows to become visible.

Throws:

SQLException - if an error occurs when setting the Predicate object

getFilter

Predicate getFilter()

Retrieves the active filter for this FilteredRowSet object.

Returns:

p the Predicate for this FilteredRowSet object; null if no filter has been set.