sirius.tagliatelle.expression

Class TransformerCast

java.lang.Object

sirius.tagliatelle.expression.TransformerCast

All Implemented Interfaces:

Expression

public class TransformerCast
extends Object
implements Expression

Invokes Transformable.as(Class) on the given selfExpression and also provides the expected type at compile time.

As currently generics aren't supported, .as() would yield Object.class as type which isn't satisfying. As we use .as() as cast operator, we simply overload this behavior, if the selfExpression is known to be a Transformable.

Constructor Summary

Constructors

Constructor and Description
TransformerCast(Expression selfExpression, Class<?> type) Creates a new invokation and compile time cast for the given expression with the given type.

Method Summary

Modifier and Type	Method and Description
Expression	copy() Creates a deep copy of the expression which can be modified without affecting the original expression.
Object	eval(LocalRenderContext ctx) Evaluates the expression into an object using the given context.
Class<?>	getType() Returns the Java class of the objects yielded by this expression.
boolean	isConstant() Determines if the expression is constant.
Expression	propagateVisitor(ExpressionVisitor visitor) Visits all child nodes and then the node itself.
Expression	reduce() Reduces and optimizes the expression if possible.

Methods inherited from class java.lang.Object

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

Constructor Detail

TransformerCast

public TransformerCast(Expression selfExpression,
                       Class<?> type)

Creates a new invokation and compile time cast for the given expression with the given type.

Parameters:

selfExpression - the expression to cast

type - the expected type

Method Detail

propagateVisitor

public Expression propagateVisitor(ExpressionVisitor visitor)

Description copied from interface: Expression

Visits all child nodes and then the node itself.

Specified by:

propagateVisitor in interface Expression

Parameters:

visitor - the visitor to invoke for all child nodes and on the node itself

Returns:

the result of the invocation of the given visitor on this node

reduce

public Expression reduce()

Description copied from interface: Expression

Reduces and optimizes the expression if possible.

Specified by:

reduce in interface Expression

Returns:

either the node itself or an optimized / reduced version if possible

copy

public Expression copy()

Description copied from interface: Expression

Creates a deep copy of the expression which can be modified without affecting the original expression.

Specified by:

copy in interface Expression

Returns:

a deep copy of the expression

isConstant

public boolean isConstant()

Description copied from interface: Expression

Determines if the expression is constant.

Specified by:

isConstant in interface Expression

Returns:

true if the expression is constant, false otherwise

eval

public Object eval(LocalRenderContext ctx)

Description copied from interface: Expression

Evaluates the expression into an object using the given context.

Specified by:

eval in interface Expression

Parameters:

ctx - the current rendering context

Returns:

the result of the evaluation

getType

public Class<?> getType()

Description copied from interface: Expression

Returns the Java class of the objects yielded by this expression.

Specified by:

getType in interface Expression

Returns:

the type of objects created by this expression