7.6. Conversion and Validation
You can specify a JSF converter for complex model properties, in either of the following ways:
<pages>
<page view-id="/calculator.jsp" action="#{calculator.calculate}">
<param name="x" value="#{calculator.lhs}"/>
<param name="y" value="#{calculator.rhs}"/>
<param name="op" converterId="com.my.calculator.OperatorConverter"
value="#{calculator.op}"/>
</page>
</pages><pages>
<page view-id="/calculator.jsp" action="#{calculator.calculate}">
<param name="x" value="#{calculator.lhs}"/>
<param name="y" value="#{calculator.rhs}"/>
<param name="op" converter="#{operatorConverter}"
value="#{calculator.op}"/>
</page>
</pages>
JSF validators, and
required="true" may also be used, in either of the following ways:
<pages>
<page view-id="/blog.xhtml">
<param name="date" value="#{blog.date}"
validatorId="com.my.blog.PastDate" required="true"/>
</page>
</pages><pages>
<page view-id="/blog.xhtml">
<param name="date" value="#{blog.date}"
validator="#{pastDateValidator}" required="true"/>
</page>
</pages>
Model-based Hibernate validator annotations are automatically recognized and validated. Seam also provides a default date converter to convert a string parameter value to a date and back.
When type conversion or validation fails, a global
FacesMessage is added to the FacesContext.
