public class GenericEnumConverter extends Object implements Converter<Enum>
The omnifaces.GenericEnumConverter is intended for use in UISelectMany components whose value is
been bound to a List<E> property where E is an enum. Even though JSF has already a
built-in EnumConverter, this doesn't work for a List<E> property as the generic type
information E is lost during runtime. The list would be filled with unconverted String
values instead which may in turn cause ClassCastException during postprocessing in the business logic.
This can be solved by using a E[] property instead of List<E> (e.g.
Role[] in case of a Role enum). If this is however is not an option due to some design
restrictions (e.g. JPA @ElementCollection, etc), then you'd need to create an explicit converter for the
enum type like follows:
@FacesConverter("roleConverter")
public class RoleConverter extends EnumConverter {
public RoleConverter() {
super(Role.class);
}
}
<h:selectManyCheckbox value="#{bean.selectedRoles}" converter="roleConverter">
<f:selectItems value="#{bean.availableRoles}" />
</h:selectManyCheckbox>
However, creating a new converter for every single enum type, only and only for use in UISelectMany with a
List<E> property, may be a bit clumsy. This generic enum converter is intended to remove the need
to create a new enum converter every time.
This converter is available by converter ID omnifaces.GenericEnumConverter. Just specify it in the
converter attribute of the multi-selection component holding <f:selectItems>.
example:
<h:selectManyCheckbox value="#{bean.selectedEnums}" converter="omnifaces.GenericEnumConverter">
<f:selectItems value="#{bean.availableEnums}" />
</h:selectManyCheckbox>
See also:
Use enum in <h:selectManyCheckbox>
This converter is not necessary anymore since JSF 2.3 thanks to the fixes in issue 1422.
<h:selectManyCheckbox value="#{bean.selectedEnums}">
<f:selectItems value="#{bean.availableEnums}" />
</h:selectManyCheckbox>
However, when you're having an input component without a value attribute, and thus the exact type cannot be automatically determined by simply inspecting the return type of the associated getter method, then this converter may be still useful.
<h:selectManyCheckbox converter="omnifaces.GenericEnumConverter">
<f:selectItems value="#{bean.availableEnums}" />
</h:selectManyCheckbox>
DATETIMECONVERTER_DEFAULT_TIMEZONE_IS_SYSTEM_TIMEZONE_PARAM_NAME| Constructor and Description |
|---|
GenericEnumConverter() |
| Modifier and Type | Method and Description |
|---|---|
Enum |
getAsObject(FacesContext context,
UIComponent component,
String submittedValue) |
String |
getAsString(FacesContext context,
UIComponent component,
Enum modelValue) |
public String getAsString(FacesContext context, UIComponent component, Enum modelValue)
getAsString in interface Converter<Enum>public Enum getAsObject(FacesContext context, UIComponent component, String submittedValue)
getAsObject in interface Converter<Enum>Copyright © 2012–2023 OmniFaces. All rights reserved.