org.apache.derby.iapi.sql.execute
Class ExecRowBuilder

java.lang.Object
  org.apache.derby.iapi.sql.execute.ExecRowBuilder

All Implemented Interfaces:

java.io.Serializable

public class ExecRowBuilder
extends java.lang.Object
implements java.io.Serializable

A class used for storing information on how to build ExecRow instances. Typically created by the compiler and used during execution to produce and reset row templates.

See Also:

Serialized Form

Field Summary

private int[]	columns Array of 1-based column numbers for the columns to access.
private int	count The number of columns to set in the row.
private boolean	indexable If true, the row should be an ExecIndexRow.
private int	maxColumnNumber The highest column number in the row.
private static long	serialVersionUID Serial version produced by the serialver utility.
private java.lang.Object[]	template Array of templates used for creating NULL values to put in the row.

Constructor Summary

ExecRowBuilder(int size, boolean indexable)
Create an instance that produces an ExecRow instance of the specified size.

Method Summary

ExecRow	build(ExecutionFactory ef) Build a new ExecRow instance with the columns specified by the setColumn(int, Object) method initialized to empty (NULL) values.
void	reset(ExecRow row) Reset a row by creating fresh NULL values.
void	setColumn(int column, java.lang.Object columnTemplate) Add a template from which a NULL value of the correct type can be created.

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

private static final long serialVersionUID

Serial version produced by the serialver utility. Needed in order to make serialization work reliably across different compilers.

See Also:

Constant Field Values

indexable

private final boolean indexable

If true, the row should be an ExecIndexRow.

template

private final java.lang.Object[] template

Array of templates used for creating NULL values to put in the row. The templates are either DataValueDescriptors or DataTypeDescriptors.

columns

private final int[] columns

Array of 1-based column numbers for the columns to access.

count

private int count

The number of columns to set in the row.

maxColumnNumber

private int maxColumnNumber

The highest column number in the row.

Constructor Detail

ExecRowBuilder

public ExecRowBuilder(int size,
                      boolean indexable)

Create an instance that produces an ExecRow instance of the specified size.

Parameters:

size - the number of columns to initialize in the produced row

indexable - true if the returned row should be an ExecIndexRow, false otherwise

Method Detail

setColumn

public void setColumn(int column,
                      java.lang.Object columnTemplate)

Add a template from which a NULL value of the correct type can be created. It should either be a DataValueDescriptor or a DataTypeDescriptor.

Parameters:

column - the column number

columnTemplate - a template from which a NULL value can be created (either a DataValueDescriptor or a DataTypeDescriptor)

build

public ExecRow build(ExecutionFactory ef)
              throws StandardException

Build a new ExecRow instance with the columns specified by the setColumn(int, Object) method initialized to empty (NULL) values.

Parameters:

ef - an execution factory used to create a row

Returns:

a row initialized with NULL values of the requested types

Throws:

StandardException

reset

public void reset(ExecRow row)
           throws StandardException

Reset a row by creating fresh NULL values.

Parameters:

row - the row to reset

Throws:

StandardException