javax.servlet.jsp.tagext
public class SimpleTagSupport extends Object implements SimpleTag
The SimpleTagSupport class is a utility class intended to be used as the base class for new simple tag handlers. The SimpleTagSupport class implements the SimpleTag interface and adds additional convenience methods including getter methods for the properties in SimpleTag.
Since: 2.0
Constructor Summary | |
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SimpleTagSupport()
Sole constructor. |
Method Summary | |
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void | doTag()
Default processing of the tag does nothing.
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static JspTag | findAncestorWithClass(JspTag from, Class klass)
Find the instance of a given class type that is closest to a given
instance.
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protected JspFragment | getJspBody()
Returns the body passed in by the container via setJspBody.
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protected JspContext | getJspContext()
Returns the page context passed in by the container via
setJspContext.
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JspTag | getParent()
Returns the parent of this tag, for collaboration purposes.
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void | setJspBody(JspFragment jspBody)
Stores the provided JspFragment.
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void | setJspContext(JspContext pc)
Stores the provided JSP context in the private jspContext field.
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void | setParent(JspTag parent)
Sets the parent of this tag, for collaboration purposes.
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Throws: JspException Subclasses can throw JspException to indicate an error occurred while processing this tag. javax.servlet.jsp.SkipPageException If the page that (either directly or indirectly) invoked this tag is to cease evaluation. A Simple Tag Handler generated from a tag file must throw this exception if an invoked Classic Tag Handler returned SKIP_PAGE or if an invoked Simple Tag Handler threw SkipPageException or if an invoked Jsp Fragment threw a SkipPageException. IOException Subclasses can throw IOException if there was an error writing to the output stream
See Also: doTag
For every instance of TagAdapter encountered while traversing the ancestors, the tag handler returned by TagAdapter.getAdaptee() - instead of the TagAdpater itself - is compared to klass. If the tag handler matches, it - and not its TagAdapter - is returned.
The current version of the specification only provides one formal way of indicating the observable type of a tag handler: its tag handler implementation class, described in the tag-class subelement of the tag element. This is extended in an informal manner by allowing the tag library author to indicate in the description subelement an observable type. The type should be a subtype of the tag handler implementation class or void. This addititional constraint can be exploited by a specialized container that knows about that specific tag library, as in the case of the JSP standard tag library.
When a tag library author provides information on the observable type of a tag handler, client programmatic code should adhere to that constraint. Specifically, the Class passed to findAncestorWithClass should be a subtype of the observable type.
Parameters: from The instance from where to start looking. klass The subclass of JspTag or interface to be matched
Returns: the nearest ancestor that implements the interface or is an instance of the class specified
Returns: the fragment encapsulating the body of this tag, or null if the action element is empty in the page.
Returns: the page context for this invocation
Returns: the parent of this tag
Parameters: jspBody The fragment encapsulating the body of this tag. If the action element is empty in the page, this method is not called at all.
See Also: SimpleTag
JspContext
via
getJspContext()
.
Parameters: pc the page context for this invocation
See Also: SimpleTag
The container invokes this method only if this tag invocation is nested within another tag invocation.
Parameters: parent the tag that encloses this tag