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}" />