org.apache.cocoon.generation
Class RequestParameterGenerator

java.lang.Object
  org.apache.avalon.framework.logger.AbstractLogEnabled
      org.apache.cocoon.xml.AbstractXMLProducer
          org.apache.cocoon.generation.AbstractGenerator
              org.apache.cocoon.generation.RequestParameterGenerator

All Implemented Interfaces:

CacheableProcessingComponent, Generator, LogEnabled, Poolable, Recyclable, SitemapModelComponent, XMLProducer

public class RequestParameterGenerator

extends AbstractGenerator

implements CacheableProcessingComponent

The RequestParameterGenerator is a simple generator producing as an output a subset of what the RequestGenerator produces.

This generator limits its output to the production of request parameters, completely ignoring things like headers and configurations. An example:

 <req:request xmlns:req="http://apache.org/cocoon/request/2.0">
   <req:requestParameters>
     <req:parameter name="aParameter">
       <req:value>itsValueitsFirstValueitsSecondValue[...]
   </req:requestParameters>
 </req:request>
 

The benefits of this simplified version of RequestGenerator is that it is cacheable. The cacheability is achieved by crafting a very specific key to be passed to Cocoon, so that the caching pipeline can actually identify the differences in parameters.

NOTE: given the nature of this generator, and the strain it might put onto the cache system, it is strongly suggested to limit its use to internal pipelines only, with a controlled number of parameter and values passed to it.

Author:

Pier Fumagalli

Field Summary

static String

PREFIX The namespace prefix of this generator.

Fields inherited from class org.apache.cocoon.generation.AbstractGenerator

objectModel, resolver, source

Fields inherited from class org.apache.cocoon.xml.AbstractXMLProducer

contentHandler, EMPTY_CONTENT_HANDLER, lexicalHandler, xmlConsumer

Fields inherited from interface org.apache.cocoon.generation.Generator

ROLE

Constructor Summary

RequestParameterGenerator()
Create a new RequestParameterGenerator instance.

Method Summary

void	generate() Generate the content and send it down to the pipeline.
Serializable	getKey() Generate the unique key.
SourceValidity	getValidity() Generate (or return) the SourceValidity instance used to possibly validate cached generations.
void	recycle() Recycle this instance by wiping all locally held references.

Methods inherited from class org.apache.cocoon.generation.AbstractGenerator

setup

Methods inherited from class org.apache.cocoon.xml.AbstractXMLProducer

setConsumer, setContentHandler, setLexicalHandler

Methods inherited from class org.apache.avalon.framework.logger.AbstractLogEnabled

enableLogging, getLogger, setupLogger, setupLogger, setupLogger

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.cocoon.xml.XMLProducer

setConsumer

Field Detail

PREFIX

public static final String PREFIX

The namespace prefix of this generator.

See Also:

Constant Field Values

Constructor Detail

RequestParameterGenerator

public RequestParameterGenerator()

Create a new RequestParameterGenerator instance.

Method Detail

recycle

public void recycle()

Recycle this instance by wiping all locally held references.

Specified by:

recycle in interface Recyclable

Overrides:

recycle in class AbstractGenerator

See Also:

Recyclable.recycle()

getKey

public Serializable getKey()

Generate the unique key.

Specified by:

getKey in interface CacheableProcessingComponent

Returns:

The generated key or null if the component is currently not cacheable.

See Also:

CacheableProcessingComponent.getKey()

getValidity

public SourceValidity getValidity()

Generate (or return) the SourceValidity instance used to possibly validate cached generations.

Specified by:

getValidity in interface CacheableProcessingComponent

Returns:

a non null SourceValidity.

See Also:

CacheableProcessingComponent.getKey()

generate

public void generate()
              throws ProcessingException,
                     SAXException,
                     IOException

Generate the content and send it down to the pipeline.

Specified by:

generate in interface Generator

Throws:

ProcessingException

SAXException

IOException

See Also:

Generator.generate()