Using the LongRangeValidator
Using the LongRangeValidator
Nest a validator tag inside the component tag and use either the validator tag's
validatorId
attribute or its binding attribute to refer to the validator.
See
for more information on using the validator attribute.
The validatorId attribute works similarly to the converterId attribute of the converter tag,
as described in
for more information on
using the binding attribute of the validator tag.
Keep in mind that validation can be performed only on components that implement
EditableValueHolder
because these components accept values that can be validated.
Using the LongRangeValidator
The Duke's Bookstore application uses a validateLongRange tag on the quantity input field of
the bookshowcart.jsp page:
<h:inputText id=
"quantity" size="4"
value=
"#{item.quantity}
" >
<f:validateLongRange minimum=
"1"/>
</h:inputText>
<h:message for=
"quantity"/>
This tag requires that the user enter a number that is at least 1. The size attribute specifies that
the number can have no more than four digits. The validateLongRange tag also has a maximum
attribute, with which you can set a maximum value of the input.
The attributes of all the standard validator tags accept value expressions. This means that the
attributes can reference backing bean properties rather than specify literal values. For example,
the validateLongRange tag in the preceding example can reference a backing bean property
called minimum to get the minimum value acceptable to the validator implementation:
<f:validateLongRange minimum=
"#{ShowCartBean.minimum}" />
Using the Standard Validators
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