er.directtoweb
Class ERDDelayedKeyValueAssignment

java.lang.Object
  com.webobjects.directtoweb.Assignment
      er.directtoweb.ERDDelayedAssignment
          er.directtoweb.ERDDelayedKeyValueAssignment

All Implemented Interfaces:

EOKeyValueArchiving, ERDComputingAssignmentInterface, Serializable

public class ERDDelayedKeyValueAssignment

extends ERDDelayedAssignment

implements ERDComputingAssignmentInterface

This is an implementation of the KeyValueAssignment implemented as a ERDDelayedAssignment. In the usual cache scheme key-value assignments are cached the first time that they are used. This may not be the intended use, i.e. you have a key value assignment with the value "session.user.firstName", the result of this computation would be cached the first time this rule is fired. With a delayed key value assignment everytime this assignment is the optimal choice from the cache it will be fired and return that result.

See Also:

Serialized Form

Nested Class Summary

Nested classes inherited from class com.webobjects.eocontrol.EOKeyValueArchiving

EOKeyValueArchiving._NullValueSupport, EOKeyValueArchiving._NumberSupport, EOKeyValueArchiving._TimestampSupport, EOKeyValueArchiving.Awaking, EOKeyValueArchiving.FinishInitialization, EOKeyValueArchiving.Support

Field Summary

Fields inherited from class com.webobjects.directtoweb.Assignment

KeyPathKey, ValueKey

Fields inherited from interface com.webobjects.eocontrol.EOKeyValueArchiving

_CLASS

Constructor Summary

ERDDelayedKeyValueAssignment(EOKeyValueUnarchiver u)
Public constructor

ERDDelayedKeyValueAssignment(String key, Object value)
Public constructor

Method Summary

static Object	decodeWithKeyValueUnarchiver(EOKeyValueUnarchiver eokeyvalueunarchiver) Static constructor required by the EOKeyValueUnarchiver interface.
NSArray	dependentKeys(String keyPath) Implementation of the ERDComputingAssignmentInterface.
Object	fireNow(D2WContext c) Implementation of the abstract method from ERDDelayedAssignment.

Methods inherited from class er.directtoweb.ERDDelayedAssignment

fire

Methods inherited from class com.webobjects.directtoweb.Assignment

encodeWithKeyValueArchiver, keyPath, toString, value, value

Methods inherited from class java.lang.Object

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

Constructor Detail

ERDDelayedKeyValueAssignment

public ERDDelayedKeyValueAssignment(EOKeyValueUnarchiver u)

Public constructor

Parameters:

u - key-value unarchiver used when unarchiving from rule files.

ERDDelayedKeyValueAssignment

public ERDDelayedKeyValueAssignment(String key,
                                    Object value)

Public constructor

Parameters:

key - context key

value - of the assignmnet

Method Detail

decodeWithKeyValueUnarchiver

public static Object decodeWithKeyValueUnarchiver(EOKeyValueUnarchiver eokeyvalueunarchiver)

Static constructor required by the EOKeyValueUnarchiver interface. If this isn't implemented then the default behavior is to construct the first super class that does implement this method. Very lame.

Parameters:

eokeyvalueunarchiver - to be unarchived

Returns:

decoded assignment of this class

dependentKeys

public NSArray dependentKeys(String keyPath)

Implementation of the ERDComputingAssignmentInterface. This assignment depends upon an array composed of the value of this assignment. This array of keys is used when constructing the significant keys for the passed in keyPath.

Specified by:

dependentKeys in interface ERDComputingAssignmentInterface

Parameters:

keyPath - to compute significant keys for.

Returns:

array of context keys this assignment depends upon.

fireNow

public Object fireNow(D2WContext c)

Implementation of the abstract method from ERDDelayedAssignment. This method is called each time this Assignment is resolved from the rule cache. For the delayed key value assignment this method simply calls valueForKeyPath on the passed in context using the value of the assignment as the key.

Specified by:

fireNow in class ERDDelayedAssignment

Parameters:

c - current D2W context

Returns:

result of valueForKeyPath called on the current context with the value of this assignment.