Package org.forgerock.openig.resolver

Interface Resolver

All Superinterfaces:

Indexed<Class>

All Known Implementing Classes:

ArrayResolver, BeanResolver, HeadersResolver, HeapResolver, ListResolver, MapResolver, PrincipalResolver, RequestResolver

public interface Resolver
extends Indexed<Class>

Exposes an object's elements for access through dynamic expressions and scripts.

Field Summary

Fields

Modifier and Type	Field	Description
static Object	UNRESOLVED	Singleton that is returned to indicate an element is not resolved by a resolver.

Method Summary

Modifier and Type	Method	Description
Object	get(Object object, Object element)	Attempts to resolve an element of an object.
Class<?>	getKey()	Returns the type of object that the resolver supports.
Object	put(Object object, Object element, Object value)	Attempts to set the value of an element of an object.

Field Detail

UNRESOLVED

static final Object UNRESOLVED

Singleton that is returned to indicate an element is not resolved by a resolver.

Method Detail

getKey

Class<?> getKey()

Returns the type of object that the resolver supports. This does not necessarily guarantee that the resolver will provide resolution; rather this is how a resolver specifies what type of object it may resolve. Resolvers for more specific classes and interfaces are called earlier than those of more general classes and interfaces.

Specified by:

getKey in interface Indexed<Class>

Returns:

the type of object that the resolver supports.

get

Object get(Object object,
           Object element)

Attempts to resolve an element of an object. The object argument references an object for which a named or indexed element is being requested. The element argument specifies the element that is being requested from the referenced object.

The element argument can be either a String or an Integer object. A string represents a named element of an associative array; an integer represents the index of an ordered array.

If the resolver cannot resolve the requested element, then UNRESOLVED should be returned. This allows other resovlers of more generic classes or interfaces to potentially resolve the requested element.

Parameters:

object - the object in which to resolve the specified element.

element - the element to resolve within the specified object.

Returns:

the value of the resolved element, or UNRESOLVED if it cannot be resolved.

put

Object put(Object object,
           Object element,
           Object value)

Attempts to set the value of an element of an object. The object argument references an object for which a named or indexed element is to be set. The element argument specifies which element value is to be set. The value argument specifies the value to be set.

The element argument can be either a String or an Integer object. A string represents a named element of an associative array; an integer represents the index of an ordered array.

If the resolver cannot resolve the requested element or set its value, then UNRESOLVED should be returned. This allows other resovlers of more generic classes or interfaces to potentially resolve the requested element.

Parameters:

object - the object in which to resolve the specified element.

element - the element within the specified object whose value is to be set.

value - the value to set the element to.

Returns:

the previous value of the element, null if no previous value, or UNRESOLVED if it cannot be resolved.