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Apache Struts 2 Documentation
FieldExpressionValidator Annotation
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Added by Rainer Hermanns, last edited by Don Brown on Nov 14, 2006 (view change)

This validator uses an OGNL expression to perform its validator. The error message will be added to the field if the expression returns false when it is evaluated against the value stack.

## Usage

The annotation must be applied at method level.

## Parameters

Parameter | Required | Default | Notes
--- | --- | --- | ---
message | yes |  | field error message
key | no |  | i18n key from language specific properties file.
fieldName | no |  |
shortCircuit | no | false | If this validator should be used as shortCircuit.
type | yes | ValidatorType.FIELD | Enum value from ValidatorType. Either FIELD or SIMPLE can be used here.
expression | yes |  | An OGNL expression that returns a boolean value.

## Examples

    @FieldExpressionValidator(message = "Default message", key = "i18n.key", shortCircuit = true, expression = "an OGNL expression")