Package org.teiid.query.sql.symbol

Class AliasSymbol

java.lang.Object

org.teiid.query.sql.symbol.Symbol

org.teiid.query.sql.symbol.AliasSymbol

All Implemented Interfaces:

Cloneable, LanguageObject, DerivedExpression, Expression

public class AliasSymbol
extends Symbol
implements DerivedExpression

An AliasSymbol wraps a SingleElementSymbol and changes it's name. AliasSymbols should be used to perform the aliasing of elements in a SELECT clause. They should typically NOT be used elsewhere in a query. The alias symbol takes on the type of it's underlying SingleElementSymbol. AliasSymbols are typically applied to ElementSymbol, ExpressionSymbol, and AggregateSymbol.

Nested Class Summary

Nested classes/interfaces inherited from interface org.teiid.query.sql.LanguageObject

LanguageObject.Util

Field Summary

Fields inherited from class org.teiid.query.sql.symbol.Symbol

outputName, SEPARATOR

Constructor Summary

Constructors

Constructor	Description
AliasSymbol(String name, Expression symbol)	Construct an AliasSymbol given the alias name and the underlying symbol.

Method Summary

Modifier and Type	Method	Description
void	acceptVisitor(LanguageVisitor visitor)	Method for accepting a visitor.
Object	clone()	Return a copy of this object.
boolean	equals(Object obj)	Compare the symbol based ONLY on name.
Expression	getSymbol()	Get the underlying symbol
Class<?>	getType()	Get the type of the symbol
void	setSymbol(Expression symbol)	Set the underlying symbol

Methods inherited from class org.teiid.query.sql.symbol.Symbol

getName, getName, getOutputName, getOutputName, getShortName, getShortName, getShortName, hashCode, setName, setOutputName, setShortName, toString

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

AliasSymbol

public AliasSymbol(String name,
                   Expression symbol)

Construct an AliasSymbol given the alias name and the underlying symbol.

Parameters:

name - Name of the alias

symbol - Underlying symbol

Method Detail

getSymbol

public Expression getSymbol()

Get the underlying symbol

Returns:

Underlying symbol

setSymbol

public void setSymbol(Expression symbol)

Set the underlying symbol

Parameters:

symbol - New symbol

getType

public Class<?> getType()

Get the type of the symbol

Specified by:

getType in interface Expression

Returns:

Type of the symbol

acceptVisitor

public void acceptVisitor(LanguageVisitor visitor)

Description copied from interface: LanguageObject

Method for accepting a visitor. It is the responsibility of the language object to call back on the visitor.

Specified by:

acceptVisitor in interface LanguageObject

Parameters:

visitor - Visitor being used

clone

public Object clone()

Return a copy of this object.

Specified by:

clone in interface LanguageObject

Specified by:

clone in class Symbol

Returns:

Deep clone of this object

equals

public boolean equals(Object obj)

Description copied from class: Symbol

Compare the symbol based ONLY on name. Symbols are not compared based on their underlying physical metadata IDs but rather on their representation in the context of a particular query. Case is not important when comparing symbol names.

Overrides:

equals in class Symbol

Parameters:

obj - Other object

Returns:

True if other obj is a Symbol (or subclass) and name is equal

See Also:

Symbol.equals(java.lang.Object)