The requiredMessage Attribute
The requiredMessage Attribute
The error messages that these tags access include:
The standard error messages that accompany the standard converters and validators that
ship with the API. See section 2.5.4 of the JavaServer Faces specification, version 1.2, for a
complete list of standard error messages.
Custom error messages contained in resource bundles registered with the application by the
application architect using the message-bundle element in the configuration file.
Custom error messages hard coded in custom converter and validator classes.
When a converter or validator is registered on an input component, the appropriate error
message is automatically queued on the component.
A page author can override the error messages queued on a component by using the following
attributes of the component's tag:
converterMessage
: References the error message to display when the data on the enclosing
component can not be converted by the converter registered on this component.
requiredMessage
: References the error message to display when no value has been entered
into the enclosing component.
validatorMessage
: References the error message to display when the data on the enclosing
component cannot be validated by the validator registered on this component.
All three attributes are enabled to take literal values and value expressions. If an attribute uses a
value expression, this expression references the error message in a resource bundle. This
resource bundle must be made available to the application in one of the following ways:
By the page author using the loadBundle tag
By the application architect using the resource-bundle element in the configuration file
Conversely, the message-bundle element must be used to make available to the application
those resource bundles containing custom error messages that are queued on the component as
a result of a custom converter or validator being registered on the component.
The bookcashier.jsp page includes an example of the requiredMessage attribute using a
value expression to reference an error message:
<h:inputText id=
"ccno" size="19"
required=
"true"
requiredMessage=
"#{customMessages.ReqMessage}" >
...
</h:inputText>
<h:message styleClass=
"error-message"
for=
"ccno"/>
The value expression that requiredMessage is using in this example references the error
message with the ReqMessage key in the resource bundle, customMessages.
Using Localized Data
Chapter 11 · Using JavaServer Faces Technology in JSP Pages
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