freemarker.template.expression
Class Identifier

java.lang.Object
  freemarker.template.expression.Identifier

All Implemented Interfaces:

Expression, Variable, java.io.Serializable

public final class Identifier
extends java.lang.Object
implements Variable, java.io.Serializable

An identifer in a variable. Can be used stand-alone to represent a variable in the root model, or combined with the Dot operator to represent models contained within hash models.

Version:

$Id: Identifier.java,v 1.2 2004/10/21 03:34:42 run2000 Exp $

See Also:

Serialized Form

Constructor Summary

Identifier(java.lang.String name)
Constructs a new Identifier with the given name.

Method Summary

boolean	equals(java.lang.Object o) Tests the equality of two Identifiers.
TemplateModel	getAsTemplateModel(TemplateModelRoot modelRoot) Gets the identifier's referent in modelRoot.
java.lang.String	getName() Retrieve the name of the identifier.
java.lang.String	getName(TemplateModelRoot modelRoot) Retrieve the name of this Identifier.
java.util.Set<ExpressionUtils.ExpressionType>	getType() Determine the type of result that can be calculated by this expression.
int	hashCode() Returns a hash code value for the Identifier.
boolean	isComplete() Has the identifier's name been assigned?
boolean	isConstant() Determine whether result calculated by this expression is a constant value.
Expression	resolveExpression() Resolves the current expression, possibly into a different expression object.
java.lang.String	toString() Returns the name of the identifier as a String.

Methods inherited from class java.lang.Object

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

Constructor Detail

Identifier

public Identifier(java.lang.String name)

Constructs a new Identifier with the given name.

Parameters:

name - the name of the identifier

Method Detail

getName

public java.lang.String getName()

Retrieve the name of the identifier.

Returns:

the name of the identifier

getName

public java.lang.String getName(TemplateModelRoot modelRoot)

Retrieve the name of this Identifier.

Specified by:

getName in interface Variable

Parameters:

modelRoot - the TemplateModelRoot used to evaluate the name of the identifier

Returns:

the name of the identifier

isComplete

public boolean isComplete()

Has the identifier's name been assigned?

Specified by:

isComplete in interface Expression

Returns:

true if the identifier is named, otherwise false

getType

public java.util.Set<ExpressionUtils.ExpressionType> getType()

Determine the type of result that can be calculated by this expression. This is in the form of an integer constant ored together from values in the ExpressionUtils class.

Specified by:

getType in interface Expression

isConstant

public boolean isConstant()

Determine whether result calculated by this expression is a constant value.

Specified by:

isConstant in interface Expression

getAsTemplateModel

public TemplateModel getAsTemplateModel(TemplateModelRoot modelRoot)
                                 throws TemplateException

Gets the identifier's referent in modelRoot.

Specified by:

getAsTemplateModel in interface Expression

Parameters:

modelRoot - the root node of the data model.

Returns:

the TemplateModel that the variable refers to.

Throws:

TemplateException - the expression could not be evaluated for some reason

toString

public java.lang.String toString()

Returns the name of the identifier as a String.

Overrides:

toString in class java.lang.Object

Returns:

the name of the identifier.

equals

public boolean equals(java.lang.Object o)

Tests the equality of two Identifiers.

Overrides:

equals in class java.lang.Object

Returns:

true if the identifiers are equal, otherwise false

hashCode

public int hashCode()

Returns a hash code value for the Identifier.

Overrides:

hashCode in class java.lang.Object

Returns:

a hash code value for this Identifier.

resolveExpression

public Expression resolveExpression()

Resolves the current expression, possibly into a different expression object. This is loosely equivalent to the serialization protocol's readResolve method. Situations where this may be used are:

• Caching frequently-used expression objects
• Evaluating constant expressions, and returning a constant reference

Specified by:

resolveExpression in interface Expression