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Assignment

Package: com.webobjects.directtoweb

Inherits from:java.lang.Object

Subclasses:


Class Description

This class performs assignments on the right-hand side of rules. Every rule in the rule database has an instance of this class that holds the right-hand-side key and the right-hand-side value. The rule engine uses this class; you should never need to use it.

If you need custom assignment behavior you can subclass Assignment. To do so, you need to provide the two constructors:

Assignment (String keyPath, Object value)
Assignment (EOKeyValueUnarchiver unarchiver)

You can invoke super for each.

You can then override the fire method to provide the value. For example, if you define a method myMethod that returns the right-hand-side value myValue for a key, the fire method could look like:

public Object fire(D2WContext context)
{
  if (value().equals("myValue")) return myMethod(context);
}

Method Types


Constructors
Static Constants

Assignment Parameters
Firing the Rule
Private Methods


Constructors


Assignment

public Assignment(String keyPath, Object value)

Creates an Assignment object and sets its key path and value.

Assignment

Assignment()

Standard Java no-argument constructor.

Assignment

public Assignment(EOKeyValueUnarchiver unarchiver)

Creates a DefaultAssignment object based on a EOKeyValueUnarchiver object. This constructor is used to read the assignment information from a rule file.
Static Constants



keyPathKey
java.lang.String

This constant is intentionally undocumented.

valueKey
java.lang.String

This constant is intentionally undocumented.
Methods


encodeWithKeyValueArchiver

public Object encodeWithKeyValueArchiver(EOKeyValueArchiver archiver)

This method is intentionally undocumented. You should never have to invoke or customize it.



fire

public Object fire(D2WContext context)

This method is invoked when a rule fires. It returns the right-hand-side value (an Object) for a right-hand-side key in the context Direct to Web context.

You can override this method to provide your own assignments.



keyPath

public String keyPath()

Returns the receiver's right-hand-side key.



toString

public String toString()

Returns a String that represents the assignment. This method is invoked when the D2WTraceRuleFiringEnabled user default is set to YES.



value

public Object value(D2WContext context)

Returns the receiver's right-hand-side value.



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