If the application developer provides an implementation of the
javax.faces.validator.Validator
interface to perform validation, you
must register this custom validator either by using the
@FacesValidator
annotation, as described in
Implementing the Validator Interface, or
by using the validator
XML element in the application configuration
resource file:
<validator>
...
<validator-id>FormatValidator</validator-id>
<validator-class>
myapplication.validators.FormatValidator
</validator-class>
<attribute>
...
<attribute-name>formatPatterns</attribute-name>
<attribute-class>java.lang.String</attribute-class>
</attribute>
</validator>
Attributes specified in a validator
tag override any settings in the
@FacesValidator
annotation.
The validator-id
and validator-class
elements are required
subelements. The validator-id
element represents the identifier under
which the Validator
class should be registered. This ID is used by the
tag class corresponding to the custom validator
tag.
The validator-class
element represents the fully qualified class name
of the Validator
class.
The attribute
element identifies an attribute associated with the
Validator
implementation. It has required attribute-name
and
attribute-class
subelements. The attribute-name
element refers to
the name of the attribute as it appears in the validator
tag. The
attribute-class
element identifies the Java type of the value
associated with the attribute.