com.klg.jclass.datasource.jdbc
Class Persistor

java.lang.Object
  |
  +--com.klg.jclass.datasource.jdbc.Persistor

All Implemented Interfaces:

PersistorModel, Serializable

public class Persistor

extends Object

implements PersistorModel, Serializable

Default mechanism for persisting (resolving) data to the originating database.

See Also:

Serialized Form

Field Summary

protected static int	ONE_ROW_CHANGED
protected PreparedStatement	update_statement

Constructor Summary

Persistor()

Method Summary

protected void	buildDeleteStatement(String table, Vector columns, Object[] original_row, com.klg.jclass.datasource.jdbc.MetaData metaData, com.klg.jclass.datasource.jdbc.DataTable dataTable) Builds the delete statement for a table.
protected void	buildUpdateStatement(String table, Vector columns, long bookmark, com.klg.jclass.datasource.jdbc.MetaData metaData, com.klg.jclass.datasource.jdbc.DataTable dataTable) Default method for building update statement.
protected void	commit(com.klg.jclass.datasource.jdbc.MetaData metaData) For internal use only.
protected int	executeUpdate(com.klg.jclass.datasource.jdbc.MetaData metaData) Commits the update to the database.
protected String	getQualifiedTableName(String table, boolean includeAlias, com.klg.jclass.datasource.jdbc.MetaData metaData) Return the qualified version of the table name, i.e., can be [catalog.][schema.]table [alias]
void	saveRow(long bookmark, com.klg.jclass.datasource.jdbc.MetaData metaDataModel, com.klg.jclass.datasource.DataTableModel dataTableModel) Persist the changes to the row to the originating data base and tables.
protected void	setUpdateParameter(int number, Object value, String col_id, com.klg.jclass.datasource.jdbc.MetaData metaData) Sets a particular parameter in the SQL update statement.
protected void	setUpdateStatement(String update, com.klg.jclass.datasource.jdbc.MetaData metaData) Sets the SQL statement to update data.
protected boolean	tablesColumnsModified(long bookmark, Vector columns, com.klg.jclass.datasource.jdbc.MetaData metaData, com.klg.jclass.datasource.jdbc.DataTable dataTable) Returns true if at least one of this table's columns been modified.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ONE_ROW_CHANGED

protected static final int ONE_ROW_CHANGED

See Also:

Constant Field Values

update_statement

protected transient PreparedStatement update_statement

Constructor Detail

Persistor

public Persistor()

Method Detail

saveRow

public void saveRow(long bookmark,
                    com.klg.jclass.datasource.jdbc.MetaData metaDataModel,
                    com.klg.jclass.datasource.DataTableModel dataTableModel)
             throws DataModelException

Description copied from interface: PersistorModel

Persist the changes to the row to the originating data base and tables.

Specified by:

saveRow in interface PersistorModel

Throws:

DataModelException - If any exception occurs.

commit

protected void commit(com.klg.jclass.datasource.jdbc.MetaData metaData)
               throws DataModelException

For internal use only. Call DataTableModel.commitRow(..) or DataModel.updateAll() instead. Actually commits this row to the server. Called by commitRow.

Throws:

DataModelException - If commit fails.

tablesColumnsModified

protected boolean tablesColumnsModified(long bookmark,
                                        Vector columns,
                                        com.klg.jclass.datasource.jdbc.MetaData metaData,
                                        com.klg.jclass.datasource.jdbc.DataTable dataTable)
                                 throws DataModelException

Returns true if at least one of this table's columns been modified.

Parameters:

bookmark - a long which uniquely identifies a row

columns - a Vector of indexes for this table's columns

Returns:

boolean, true if one or more columns were modified

DataModelException

buildDeleteStatement

protected void buildDeleteStatement(String table,
                                    Vector columns,
                                    Object[] original_row,
                                    com.klg.jclass.datasource.jdbc.MetaData metaData,
                                    com.klg.jclass.datasource.jdbc.DataTable dataTable)
                             throws DataModelException

Builds the delete statement for a table.

Parameters:

table - a String name for the table

columns - a Vector of column indexes

Throws:

DataModelException - If creation of delete statement fails.

buildUpdateStatement

protected void buildUpdateStatement(String table,
                                    Vector columns,
                                    long bookmark,
                                    com.klg.jclass.datasource.jdbc.MetaData metaData,
                                    com.klg.jclass.datasource.jdbc.DataTable dataTable)
                             throws DataModelException

Default method for building update statement. Loops on columns and builds a PreparedStatement.

Throws:

DataModelException - If build fails.

getQualifiedTableName

protected String getQualifiedTableName(String table,
                                       boolean includeAlias,
                                       com.klg.jclass.datasource.jdbc.MetaData metaData)

Return the qualified version of the table name, i.e., can be [catalog.][schema.]table [alias]

setUpdateStatement

protected void setUpdateStatement(String update,
                                  com.klg.jclass.datasource.jdbc.MetaData metaData)
                           throws DataModelException

Sets the SQL statement to update data. Statement can be sql statement or a stored procedure.

Throws:

DataModelException - If setUpdateStatement fails.

setUpdateParameter

protected void setUpdateParameter(int number,
                                  Object value,
                                  String col_id,
                                  com.klg.jclass.datasource.jdbc.MetaData metaData)
                           throws DataModelException

Sets a particular parameter in the SQL update statement. The update statement is automatically built.

Parameters:

number - an int indicating the position of the parameter

value - the Object which is to be set

col_id - column_name the column alias or column name as it appears in the select statement ([catalog.][schema.][table.]column)

Throws:

DataModelException - If setUpdatdParameter fails.

executeUpdate

protected int executeUpdate(com.klg.jclass.datasource.jdbc.MetaData metaData)
                     throws DataModelException

Commits the update to the database.

Returns:

rows_affected an int indicating the number of rows affected

Throws:

DataModelException - thrown if query fails