org.springframework.extensions.surf.taglib

Class RenderServiceTag

java.lang.Object

javax.servlet.jsp.tagext.TagSupport

org.springframework.web.servlet.tags.RequestContextAwareTag

org.springframework.extensions.surf.taglib.RenderServiceTag

All Implemented Interfaces:

Serializable, javax.servlet.jsp.tagext.IterationTag, javax.servlet.jsp.tagext.JspTag, javax.servlet.jsp.tagext.Tag, javax.servlet.jsp.tagext.TryCatchFinally

Direct Known Subclasses:

AbstractObjectTag, ComponentTag, IncludeTag, RegionTag, ResourceTag, StylesheetTag, SurfBugInclude

public abstract class RenderServiceTag
extends org.springframework.web.servlet.tags.RequestContextAwareTag

An abstract RequestContextAwareTag intended to be sub-classed by custom JSP tags that require access to a RenderService for rendering Spring Surf objects (such as pages, templates, components, etc). It extends the Spring provided RequestContextAwareTag class in order to access the WebApplicationContext from which to retrieve a RenderService interface implementing bean. If no bean is found then the JSP will render an error message indicating the cause of the problem (ideally this will be detected during development rather than in product release). If more than one RenderService is found then it will use the first that is a RenderServiceImpl instance, and if one is not found will simply use the first bean retrieved.

Although the Spring Surf defines a RenderServiceImpl with a known bean id, it is not directly looked up because this would prevent alternative services being set through custom configuration. To ensure that an alternative RenderService from the default Spring Surf configured bean is used you must override the default bean (that is re-use the bean id: "webframework.service.render").

Author:

David Draper

See Also:

Serialized Form

Field Summary

Fields inherited from class org.springframework.web.servlet.tags.RequestContextAwareTag

REQUEST_CONTEXT_PAGE_ATTRIBUTE

Fields inherited from class javax.servlet.jsp.tagext.TagSupport

id, pageContext

Fields inherited from interface javax.servlet.jsp.tagext.IterationTag

EVAL_BODY_AGAIN

Fields inherited from interface javax.servlet.jsp.tagext.Tag

EVAL_BODY_INCLUDE, EVAL_PAGE, SKIP_BODY, SKIP_PAGE

Constructor Summary

Constructors

Constructor and Description
RenderServiceTag()

Method Summary

Methods

Modifier and Type	Method and Description
protected int	doStartTagInternal() Attempts to find a RenderService bean to provide to subclasses to use for rendering.
protected abstract int	invokeRenderService(RenderService renderService, RequestContext renderContext, ModelObject object) This method should be implemented to invoke the required method of the RenderService that the subclass needs to render its output

Methods inherited from class org.springframework.web.servlet.tags.RequestContextAwareTag

doCatch, doFinally, doStartTag, getRequestContext

Methods inherited from class javax.servlet.jsp.tagext.TagSupport

doAfterBody, doEndTag, findAncestorWithClass, getId, getParent, getValue, getValues, release, removeValue, setId, setPageContext, setParent, setValue

Methods inherited from class java.lang.Object

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

Constructor Detail

RenderServiceTag

public RenderServiceTag()

Method Detail

doStartTagInternal

protected final int doStartTagInternal()
                                throws Exception

Attempts to find a RenderService bean to provide to subclasses to use for rendering. If no RenderService bean is defined in then an error message will be rendered without invoking any subclass code. If more than one RenderService is found then it will attempt to use the default Spring Surf implementation. Failing that it will use the first RenderService bean found.

Specified by:

doStartTagInternal in class org.springframework.web.servlet.tags.RequestContextAwareTag

Throws:

Exception

invokeRenderService

protected abstract int invokeRenderService(RenderService renderService,
                      RequestContext renderContext,
                      ModelObject object)
                                    throws Exception

This method should be implemented to invoke the required method of the RenderService that the subclass needs to render its output

Parameters:

renderService - RenderService

renderContext - RequestContext

object - ModelObject

Returns:

The appropriate return code to pass on (e.g. SKIP_BODY, EVAL_BODY_INCLUDE, etc).

Throws:

Exception