You can drag the Message Group component from
the Palette's Basic category to the Visual Designer to create a list of global messages
for a page, such as system runtime errors, or a list of messages related to components. To show individual component errors, such as
validation and conversion errors, deselect
the
showGlobalOnly
property in the Message Group Properties Window.
The two message components, Message Group and Message, display error messages concerning component rendering and validation.
You can send your own error text to a Message Group component by calling the corresponding Java object's info, error
,
fatal,
or warn
method. The component displays an appropriate icon for the type of method called.
You can also write your own input validation methods, which can write text to the Message Group component by throwing ValidatorException(new FacesMessage (String))
. If you do not want to throw an exception, you can have the validation method call the Java object's info, error
,
fatal,
or warn
method instead.