org.springframework.expression
Interface EvaluationContext

All Known Implementing Classes:

StandardEvaluationContext

public interface EvaluationContext

Expressions are executed in an evaluation context. It is in this context that references are resolved when encountered during expression evaluation.

There is a default implementation of the EvaluationContext, StandardEvaluationContext that can be extended, rather than having to implement everything.

Since:

3.0

Author:

Andy Clement, Juergen Hoeller

Method Summary

List<ConstructorResolver>	getConstructorResolvers()
List<MethodResolver>	getMethodResolvers()
OperatorOverloader	getOperatorOverloader()
List<PropertyAccessor>	getPropertyAccessors()
TypedValue	getRootObject()
TypeComparator	getTypeComparator()
TypeConverter	getTypeConverter()
TypeLocator	getTypeLocator()
Object	lookupVariable(String name) Look up a named variable within this evaluation context.
void	setVariable(String name, Object value) Set a named variable within this evaluation context to a specified value.

Method Detail

getRootObject

TypedValue getRootObject()

Returns:

the default root context object against which unqualified properties/methods/etc should be resolved. This can be overridden when evaluating an expression.

getConstructorResolvers

List<ConstructorResolver> getConstructorResolvers()

Returns:

a list of resolvers that will be asked in turn to locate a constructor

getMethodResolvers

List<MethodResolver> getMethodResolvers()

Returns:

a list of resolvers that will be asked in turn to locate a method

getPropertyAccessors

List<PropertyAccessor> getPropertyAccessors()

Returns:

a list of accessors that will be asked in turn to read/write a property

getTypeLocator

TypeLocator getTypeLocator()

Returns:

a type locator that can be used to find types, either by short or fully qualified name.

getTypeConverter

TypeConverter getTypeConverter()

Returns:

a type converter that can convert (or coerce) a value from one type to another.

getTypeComparator

TypeComparator getTypeComparator()

Returns:

a type comparator for comparing pairs of objects for equality.

getOperatorOverloader

OperatorOverloader getOperatorOverloader()

Returns:

an operator overloader that may support mathematical operations between more than the standard set of types

setVariable

void setVariable(String name,
                 Object value)

Set a named variable within this evaluation context to a specified value.

Parameters:

name - variable to set

value - value to be placed in the variable

lookupVariable

Object lookupVariable(String name)

Look up a named variable within this evaluation context.

Parameters:

name - variable to lookup

Returns:

the value of the variable