Package org.apache.wiki.tags

Provides standard JSP tags for JSPWiki.

See:
Description

Interface Summary

ParamHandler

Interface to be implemented by any tag that wishes to contain a wiki:param tag for passing dynamic name-value pairs.

Class Summary

AdminBeanIteratorInfo	Just provides iteration support for AdminBeanIteratorTag
AdminBeanIteratorTag	Provides an iterator for all AdminBeans of a given type.
AttachmentsIteratorInfo	Just provides the TEI data for AttachmentsIteratorTag.
AttachmentsIteratorTag	Iterates through the list of attachments one has.
AuthorTag	Writes the author name of the current page, including a link to that page, if that page exists.
BaseURLTag	Writes the jspwiki.baseURL property.
BreadcrumbsTag	Implement a "breadcrumb" (most recently visited) trail.
BreadcrumbsTag.FixedQueue	Extends the LinkedList class to provide a fixed-size queue implementation
CalendarTag	Provides a nice calendar.
CheckLockInfo	A companion to CheckLogTag.
CheckLockTag	Checks whether the page is locked for editing.
CheckRequestContextTag	Includes body, if the request context matches.
CheckVersionTag	Does a version check on the page.
CommentLinkTag	Writes a comment link.
ContentEncodingTag	Returns the app name.
ContentTag	Is used as a "super include" tag, which can include the proper context based on the wikicontext.
CookieTag	Sets or gets Cookie values.
DiffLinkTag	Writes a diff link.
EditLinkTag	Writes an edit link.
EditorIteratorInfo	Just provides the TEI data for EditorIteratorTag.
EditorIteratorTag	Iterates through editors.
EditorTag	Creates an editor component with all the necessary parts to get it working.
FeedDiscoveryTag	Outputs links to all the site feeds and APIs this Wiki/blog supports.
HasAttachmentsTag	Includes body if page has attachments.
HistoryIteratorInfo	Just provides the TEI data for HistoryIteratorTag.
HistoryIteratorTag	Iterates through tags.
IfNoSearchResultsTag	If there have been no search results, then outputs the body text.
IncludeResourcesTag	This tag is used to include any programmatic includes into the output stream.
IncludeTag	Includes an another JSP page, making sure that we actually pass the WikiContext correctly.
InsertDiffTag	Writes difference between two pages using a HTML table.
InsertPageTag	Renders WikiPage content.
IteratorTag	Iterates through tags.
LinkTag	Provides a generic link tag for all kinds of linking purposes.
LinkToParentTag	Writes a link to a parent of a Wiki page.
LinkToTag	Writes a link to a Wiki page.
MessagesTag	Returns or clears the current messages associated with the user's wiki session.
NextVersionTag	Writes the version number of the next version of the page.
NoSuchPageTag	Includes the body in case there is no such page available.
PageDateTag	Writes the modification date of the page, formatted as specified in the attribute "format".
PageExistsTag	Includes the body in case the set page does exist.
PageInfoLinkTag	Writes a link to the Wiki PageInfo.
PageNameTag	Returns the currently requested page name.
PageSizeTag	Returns the currently requested page or attachment size.
PageTypeTag	Includes the body, if the current page is of proper type.
PageVersionTag	Writes the version of the current page.
ParamTag	ParamTag submits name-value pairs to the first enclosing ParamHandler instance.
ParentPageNameTag	Returns the parent of the currently requested page.
PermissionTag	Tells whether the user in the current wiki context possesses a particular permission.
PluginTag	Inserts any Wiki plugin.
PreviousVersionTag	Outputs the version number of the previous version of this page.
RequestResourceTag	Provides easy access to TemplateManager.addResourceRequest().
RSSImageLinkTag	Writes an image link to a JSPWiki RSS file.
SearchResultIteratorInfo	Just provides the TEI data for IteratorTag.
SearchResultIteratorTag	Iterates through Search result results.
SearchResultsSizeTag	Outputs the size of the search results list, if it contains any items.
SearchResultsTag	Includes the body content, if there are any search results.
SetPaginationTag	Calculate pagination string.
TabbedSectionTag	Generates tabbed page section: container for the Tab tag.
TabTag	Generates single tabbed page layout.
TemplateDirTag	Returns the currently used template.
TranslateTag	Converts the body text into HTML content.
UploadLinkTag	Writes a link to the upload page.
UserCheckTag	Includes the content if an user check validates.
UserNameTag	Returns the current user name, or empty, if the user has not been validated.
UserProfileTag	Returns user profile attributes, or empty strings if the user has not been validated.
VariableTag	Returns the value of an Wiki variable.
WikiBodyTag	This is a class that provides the same services as the WikiTagBase, but this time it works for the BodyTagSupport base class.
WikiLinkTag	Root class for different internal wiki links.
WikiTagBase	Base class for JSPWiki tags.

Package org.apache.wiki.tags Description

Provides standard JSP tags for JSPWiki.

Package specification

This package contains a diverse set of JSP tags which are used in the template pages.

Managing tag pooling

A typical problem for many tag developers is that many web containers pool tags, i.e. the tag is not released after doEndTag(), but put into a pool, from which it can be invoked again. This is highly efficient, as you don't need to instantiate the tag again.

The problem, however, is that when your tag is put back into the pool, it still retains all the internal references, i.e. none of the member fields are cleared. This means there can be dangling references to things which will take a lot of memory. In JSPWiki's case, the WikiContext is a good example: it can actually contain quite a lot of stuff accumulated during it's life time, and therefore it's important for memory use that all references are cleared.

Unfortunately, the "easy" solution of implementing your custom release handler in Tag.release() does not help, since it is called only when the tag is truly and completely released from the pool. So, as long as the tag sits in the pool, release() is not called, and your references keep on dangling like wet spaghetti off the balcony.

Neither can you trust e.g. doEndTag() being called every time, since e.g. if there is an exception, doEndTag() is never called.

The correct way to do reference cleaning is to implement the TryCatchFinally interface, where the doFinally() method is called every time the tag has been finished with and prior to it being put back into the pool. Most JSPWiki base tag classes IteratorTag and WikiTagBase implement the TryCatchFinally interface, which means that any class subclassed from them also allows has those methods.

Check out the javadocs for the tags for more info!

Related documentation

TBD.