org.apache.ws.jaxme.sqls.impl

Class VirtualColumn

java.lang.Object

org.apache.ws.jaxme.sqls.impl.AbstractColumn

org.apache.ws.jaxme.sqls.impl.VirtualColumn

All Implemented Interfaces:

BinaryColumn, Column, ColumnReference, StringColumn

public class VirtualColumn
extends AbstractColumn
implements ColumnReference

A virtual column is a named item that can be added to the result set. For example:

   SELECT name, vorname, MAX(a) AS max FROM ...
 

The example uses a virtual column max. The value of max is calculated from other values.

Author:

Jochen Wiedmann

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.ws.jaxme.sqls.Column

Column.Name, Column.Type

Constructor Summary

Constructors

Constructor and Description
VirtualColumn(Column.Name pName, Column.Type pType)
VirtualColumn(java.lang.String pName, Column.Type pType)

Method Summary

Methods

Modifier and Type	Method and Description
Column.Name	getAlias() Returns the references alias name, if any.
Column	getColumn() Returns the referenced Column.
java.lang.String	getQName() Returns the columns fully qualified name, which is getTable().getQName() + "." + getName().
Table	getTable() Returns the columns table.
TableReference	getTableReference() Returns the TableReference that created the column reference.
java.lang.Object	getValue()
boolean	isPrimaryKeyPart() Returns whether this column is part of the primary key.
boolean	isVirtual() Returns whether this column is a true column or a virtual column.
void	setAlias(Column.Name pName) Sets the references alias name, if any.
void	setAlias(java.lang.String pName) Sets the references alias name, if any.
void	setValue(Function pValue)
void	setValue(SelectStatement pValue)
void	setValue(java.lang.String pValue)

Methods inherited from class org.apache.ws.jaxme.sqls.impl.AbstractColumn

equals, getCustomData, getLength, getName, getType, hasFixedLength, hashCode, isBinaryColumn, isNullable, isStringColumn, setCustomData, setLength, setLength, setNullable

Methods inherited from class java.lang.Object

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

Constructor Detail

VirtualColumn

public VirtualColumn(Column.Name pName,
             Column.Type pType)

VirtualColumn

public VirtualColumn(java.lang.String pName,
             Column.Type pType)

Method Detail

getTable

public Table getTable()

Description copied from interface: Column

Returns the columns table.

Specified by:

getTable in interface Column

getQName

public java.lang.String getQName()

Description copied from interface: Column

Returns the columns fully qualified name, which is getTable().getQName() + "." + getName().

Specified by:

getQName in interface Column

isPrimaryKeyPart

public boolean isPrimaryKeyPart()

Description copied from interface: Column

Returns whether this column is part of the primary key.

Specified by:

isPrimaryKeyPart in interface Column

getTableReference

public TableReference getTableReference()

Description copied from interface: ColumnReference

Returns the TableReference that created the column reference.

Specified by:

getTableReference in interface ColumnReference

getColumn

public Column getColumn()

Description copied from interface: ColumnReference

Returns the referenced Column.

Specified by:

getColumn in interface ColumnReference

isVirtual

public boolean isVirtual()

Description copied from interface: Column

Returns whether this column is a true column or a virtual column.

Specified by:

isVirtual in interface Column

setAlias

public void setAlias(java.lang.String pName)

Description copied from interface: ColumnReference

Sets the references alias name, if any. Null indicates, that an alias name may be choosen.

Specified by:

setAlias in interface ColumnReference

setAlias

public void setAlias(Column.Name pName)

Description copied from interface: ColumnReference

Sets the references alias name, if any. Null indicates, that an alias name may be choosen.

Specified by:

setAlias in interface ColumnReference

getAlias

public Column.Name getAlias()

Description copied from interface: ColumnReference

Returns the references alias name, if any. Null indicates, that an alias name may be choosen.

Specified by:

getAlias in interface ColumnReference

setValue

public void setValue(java.lang.String pValue)

setValue

public void setValue(SelectStatement pValue)

setValue

public void setValue(Function pValue)

getValue

public java.lang.Object getValue()