public abstract class JspFragment extends Object
The definition of the JSP fragment must only contain template text and JSP action elements. In other words, it must not contain scriptlets or scriptlet expressions. At translation time, the container generates an implementation of the JspFragment abstract class capable of executing the defined fragment.
A tag handler can invoke the fragment zero or more times, or pass it along to other tags, before returning. To communicate values to/from a JSP fragment, tag handlers store/retrieve values in the JspContext associated with the fragment.
Note that tag library developers and page authors should not generate JspFragment implementations manually.
Implementation Note: It is not necessary to generate a separate class for each fragment. One possible implementation is to generate a single helper class for each page that implements JspFragment. Upon construction, a discriminator can be passed to select which fragment that instance will execute.
Constructor and Description |
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JspFragment() |
Modifier and Type | Method and Description |
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abstract JspContext |
getJspContext()
Returns the JspContext that is bound to this JspFragment.
|
abstract void |
invoke(Writer out)
Executes the fragment and directs all output to the given Writer,
or the JspWriter returned by the getOut() method of the JspContext
associated with the fragment if out is null.
|
public abstract void invoke(Writer out) throws JspException, IOException
out
- The Writer to output the fragment to, or null if
output should be sent to JspContext.getOut().JspException
- Thrown if an error occured
while invoking this fragment.SkipPageException
- Thrown if the page
that (either directly or indirectly) invoked the tag handler that
invoked this fragment is to cease evaluation. The container
must throw this exception if a Classic Tag Handler returned
Tag.SKIP_PAGE or if a Simple Tag Handler threw SkipPageException.IOException
- If there was an error writing to the
stream.public abstract JspContext getJspContext()
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