org.sitemesh.tagprocessor
Class BasicBlockRule<T>

java.lang.Object
  org.sitemesh.tagprocessor.BasicRule
      org.sitemesh.tagprocessor.BasicBlockRule<T>

All Implemented Interfaces:

TagRule

Direct Known Subclasses:

ContentBlockExtractingRule, DivExtractingRule, ExportTagToContentRule, SiteMeshDecorateRule, SiteMeshWriteRule, TitleExtractingRule

public abstract class BasicBlockRule<T>
extends BasicRule

TagRule helper class for dealing with blocks surrounded by an opening and closing tag. e.g. <tag>...</tag>.

Subclasses should implement processStart(Tag) and processEnd(Tag, Object), which get called at the start and end of the block, respectively. Optionally, data may be passed between the two by returning an object from processStart(Tag) which will get passed to the matching processEnd(Tag, Object) call, even if there are nested tags. The class type of data used matches the generic type T of this class.

Author:

Joe Walnes

Field Summary

Fields inherited from class org.sitemesh.tagprocessor.BasicRule

tagProcessorContext

Constructor Summary

BasicBlockRule()

Method Summary

void	process(Tag tag) Implementations can use this to do any necessary work on the Tag such as extracting values or transforming it.
protected abstract void	processEnd(Tag tag, T data) Called when a block is ended (i.e.
protected abstract T	processStart(Tag tag) Called when a block is started (i.e.

Methods inherited from class org.sitemesh.tagprocessor.BasicRule

setTagProcessorContext

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BasicBlockRule

public BasicBlockRule()

Method Detail

processStart

protected abstract T processStart(Tag tag)
                           throws IOException

Called when a block is started (i.e. <opening> tag is encountered).

Parameters:

tag - Opening tag.

Returns:

Any data that needs to be passed to processEnd(Tag, Object). May be null.

Throws:

IOException

processEnd

protected abstract void processEnd(Tag tag,
                                   T data)
                            throws IOException

Called when a block is ended (i.e. </closing> tag is encountered).

Parameters:

tag - Closing tag. This will not have any attributes available (as they are associated with an opening tag. To get access to the attributes, the processStart(Tag) method should access them and return them as data.

data - Data returned from processStart(Tag). May be null.

Throws:

IOException

process

public void process(Tag tag)
             throws IOException

Description copied from interface: TagRule

Implementations can use this to do any necessary work on the Tag such as extracting values or transforming it.

Specified by:

process in interface TagRule

Specified by:

process in class BasicRule

Throws:

IOException