org.apache.cocoon.taglib
Interface IterationTag

All Superinterfaces:

Component, Tag

All Known Subinterfaces:

BodyTag

All Known Implementing Classes:

ForEachSupport, ForEachTag, IterationTestTag, LoopTagSupport, MonthsTag, UIComponentBodyTag, VerbatimTag

public interface IterationTag
extends Tag

The IterationTag interface extends Tag by defining one additional method that controls the reevaluation of its body.

A tag handler that implements IterationTag is treated as one that implements Tag regarding the doStartTag() and doEndTag() methods. IterationTag provides a new method: doAfterBody().

The doAfterBody() method is invoked after every body evaluation to control whether the body will be reevaluated or not. If doAfterBody() returns IterationTag.EVAL_BODY_AGAIN, then the body will be reevaluated. If doAfterBody() returns Tag.SKIP_BODY, then the body will be skipped and doEndTag() will be evaluated instead.

Version:

CVS $Id: IterationTag.html 1304258 2012-03-23 10:09:27Z ilgrosso $

Author:

Volker Schmitt

Field Summary

static int

EVAL_BODY_AGAIN Request the reevaluation of some body.

Fields inherited from interface org.apache.cocoon.taglib.Tag

EVAL_BODY, EVAL_PAGE, ROLE, SKIP_BODY

Method Summary

int	doAfterBody() Process body (re)evaluation.

Methods inherited from interface org.apache.cocoon.taglib.Tag

doEndTag, doStartTag, getParent, setParent, setup

Field Detail

EVAL_BODY_AGAIN

static final int EVAL_BODY_AGAIN

Request the reevaluation of some body. Returned from doAfterBody.

See Also:

Constant Field Values

Method Detail

doAfterBody

int doAfterBody()
                throws SAXException

Process body (re)evaluation. This method is invoked by the Taglib implementation object after every evaluation of the body into the BodyEvaluation object. The method is not invoked if there is no body evaluation.

If doAfterBody returns EVAL_BODY_AGAIN, a new evaluation of the body will happen (followed by another invocation of doAfterBody). If doAfterBody returns SKIP_BODY no more body evaluations will occur and then doEndTag will be invoked.

The method re-invocations may be lead to different actions because there might have been some changes to shared state, or because of external computation.

Returns:

whether additional evaluations of the body are desired

Throws:

SAXException