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EOQualifierVariable


Inherits from:
(com.apple.client.eocontrol) Object
(com.apple.yellow.eocontrol) NSObject
Implements:
(com.apple.client.eocontrol only) NSCoding
Package:
com.apple.client.eocontrol
com.apple.yellow.eocontrol


Class Description


EOQualifierVariable defines objects that serve as placeholders in the qualifier. When you create a qualifier programmatically, you typically do something like this:

aQual = [EOQualifier qualifierWithQualifierFormat:"dateReleased = %@", aDate];

where aDate is a variable that contains the actual date you want to query upon. When you store the qualifier in an EOModel, there is no way to know the actual value to query upon or the variable that will contain that value. The EOQualifierVariable object acts as a placeholder for the actual variable that will represent the right side of the expression. You specify an EOQualifierVariable by using a $, as in the following:

dateReleased = $aDate

Variable values must be substituted for using qualifierWithBindings.




Constants


(com.apple.yellow.eocontrol only) EOQualifierVariable defines the following String constant as the type of exception that's raised when an EOQualifierVariable object requires bindings for all its variables and one or more variable is missing from the bindings (see qualifierWithBindings in the EOQualifier class specification):



Interfaces Implemented


NSCoding
classForCoder
encodeWithCoder


Constructors



EOQualifierVariable

public EOQualifierVariable(String key)

Creates and returns a new EOQualifierVariable object with the specified name. For example, if your qualifier is "dateReleased = $aDate", then this method would be invoked with the key "aDate".


Static Methods



variableWithKey

public static Object variableWithKey(String key)

(com.apple.yellow.eocontrol only) Creates and returns a new EOQualifierVariable object with the specified key. For example, if your qualifier is "dateReleased = $aDate", then this method would be invoked with the key "aDate".


Instance Methods



key

public String key()

Returns the key of the variable qualifier.


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