public abstract class ConverterELTag extends TagSupport
ConverterELTag is a base class for all Jakarta Server Pages custom
actions that create and register a Converter
instance on
the ValueHolder
associated with our most immediate
surrounding instance of a tag whose implementation class is a
subclass of UIComponentClassicTagBase
. To avoid creating duplicate
instances when a page is redisplayed, creation and registration of a
Converter
occurs only if the corresponding
UIComponent
was created (by the owning UIComponentTag
) during the execution of the current page.
This class may be used as a base class for tag instances that
support specific Converter
subclasses.
Subclasses of this class must implement the
createConverter()
method, which creates and returns a
Converter
instance. Any configuration properties that specify
behavior of this Converter
must have been set by the
createConverter()
method. Generally, this occurs
by copying corresponding attribute values on the tag instance.
This tag creates no output to the page currently being created. It
is used solely for the side effect of Converter
creation.
id, pageContext
EVAL_BODY_AGAIN
EVAL_BODY_INCLUDE, EVAL_PAGE, SKIP_BODY, SKIP_PAGE
Constructor and Description |
---|
ConverterELTag() |
Modifier and Type | Method and Description |
---|---|
protected abstract Converter |
createConverter()
Create and return a new
Converter to be registered
on our surrounding UIComponent . |
int |
doStartTag()
Create a new instance of the specified
Converter
class, and register it with the UIComponent instance associated
with our most immediately surrounding UIComponentClassicTagBase instance, if
the UIComponent instance was created by this execution of the
containing Jakarta Server Pages page. |
doAfterBody, doEndTag, findAncestorWithClass, getId, getParent, getValue, getValues, release, removeValue, setId, setPageContext, setParent, setValue
public int doStartTag() throws JspException
Create a new instance of the specified Converter
class, and register it with the UIComponent
instance associated
with our most immediately surrounding UIComponentClassicTagBase
instance, if
the UIComponent
instance was created by this execution of the
containing Jakarta Server Pages page. If the localValue of the
UIComponent
is a String, attempt to convert it.
doStartTag
in interface Tag
doStartTag
in class TagSupport
JspException
- if a Jakarta Server Pages error occursTag.doStartTag()
protected abstract Converter createConverter() throws JspException
Create and return a new Converter
to be registered
on our surrounding UIComponent
.
Converter
JspException
- if a new instance cannot be created