Spring Framework

org.springframework.context.expression
Class EnvironmentAccessor

java.lang.Object
  extended by org.springframework.context.expression.EnvironmentAccessor
All Implemented Interfaces:
PropertyAccessor

public class EnvironmentAccessor
extends java.lang.Object
implements PropertyAccessor

Read-only EL property accessor that knows how to retrieve keys of a Spring Environment instance.

Since:
3.1
Author:
Chris Beams

Constructor Summary
EnvironmentAccessor()
           
 
Method Summary
 boolean canRead(EvaluationContext context, java.lang.Object target, java.lang.String name)
          Can read any Environment, thus always returns true.
 boolean canWrite(EvaluationContext context, java.lang.Object target, java.lang.String name)
          Read only.
 java.lang.Class<?>[] getSpecificTargetClasses()
          Return an array of classes for which this resolver should be called.
 TypedValue read(EvaluationContext context, java.lang.Object target, java.lang.String name)
          Access the given target object by resolving the given property name against the given target environment.
 void write(EvaluationContext context, java.lang.Object target, java.lang.String name, java.lang.Object newValue)
          Read only.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

EnvironmentAccessor

public EnvironmentAccessor()
Method Detail

getSpecificTargetClasses

public java.lang.Class<?>[] getSpecificTargetClasses()
Description copied from interface: PropertyAccessor
Return an array of classes for which this resolver should be called. Returning null indicates this is a general resolver that can be called in an attempt to resolve a property on any type.

Specified by:
getSpecificTargetClasses in interface PropertyAccessor
Returns:
an array of classes that this resolver is suitable for (or null if a general resolver)

canRead

public boolean canRead(EvaluationContext context,
                       java.lang.Object target,
                       java.lang.String name)
                throws AccessException
Can read any Environment, thus always returns true.

Specified by:
canRead in interface PropertyAccessor
Parameters:
context - the evaluation context in which the access is being attempted
target - the target object upon which the property is being accessed
name - the name of the property being accessed
Returns:
true
Throws:
AccessException - if there is any problem determining whether the property can be read

read

public TypedValue read(EvaluationContext context,
                       java.lang.Object target,
                       java.lang.String name)
                throws AccessException
Access the given target object by resolving the given property name against the given target environment.

Specified by:
read in interface PropertyAccessor
Parameters:
context - the evaluation context in which the access is being attempted
target - the target object upon which the property is being accessed
name - the name of the property being accessed
Returns:
a TypedValue object wrapping the property value read and a type descriptor for it
Throws:
AccessException - if there is any problem accessing the property value

canWrite

public boolean canWrite(EvaluationContext context,
                        java.lang.Object target,
                        java.lang.String name)
                 throws AccessException
Read only.

Specified by:
canWrite in interface PropertyAccessor
Parameters:
context - the evaluation context in which the access is being attempted
target - the target object upon which the property is being accessed
name - the name of the property being accessed
Returns:
false
Throws:
AccessException - if there is any problem determining whether the property can be written to

write

public void write(EvaluationContext context,
                  java.lang.Object target,
                  java.lang.String name,
                  java.lang.Object newValue)
           throws AccessException
Read only. No-op.

Specified by:
write in interface PropertyAccessor
Parameters:
context - the evaluation context in which the access is being attempted
target - the target object upon which the property is being accessed
name - the name of the property being accessed
newValue - the new value for the property
Throws:
AccessException - if there is any problem writing to the property value

Spring Framework