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

Sets the Key for type conversion.

## Usage

The Key annotation must be applied at field level.

## Parameters

Parameter | Required | Default | Description
--- | --- | --- | ---
value | no | java.lang.Object.class | The key property value.

## Examples

    // The key property for User objects within the users collection is the <code>userName</code> attribute.
    @Key( value = java.lang.Long.class )
    private Map<Long, User> userMap;