org.apache.cocoon.components.pipeline
Interface EventPipeline

All Superinterfaces:

org.apache.avalon.framework.component.Component, org.apache.avalon.framework.component.Composable, org.apache.avalon.excalibur.pool.Poolable, org.apache.avalon.framework.component.Recomposable, org.apache.avalon.excalibur.pool.Recyclable, XMLProducer

All Known Implementing Classes:

AbstractEventPipeline

public interface EventPipeline

extends XMLProducer, org.apache.avalon.framework.component.Component, org.apache.avalon.framework.component.Recomposable, org.apache.avalon.excalibur.pool.Recyclable

A pipeline that produces SAX events using a Generator and zero or more Transformers.

An EventPipeline is Recomposable since the ComponentManager used to get the generator and transformers depends on the pipeline assembly engine where they are defined (i.e. a given sitemap file).

Version:

CVS $Id: EventPipeline.java,v 1.4 2002/02/22 07:00:11 cziegeler Exp $

Author:

Giacomo Pati

Field Summary

static java.lang.String

ROLE

Method Summary

void	addTransformer(java.lang.String role, java.lang.String source, org.apache.avalon.framework.parameters.Parameters param) Add a transformer at the end of the pipeline.
Generator	getGenerator() Get the generator used by this pipeline.
boolean	process(Environment environment) Process the given Environment, producing the output.
void	setGenerator(java.lang.String role, java.lang.String source, org.apache.avalon.framework.parameters.Parameters param) Set the generator that will be used as the initial step in the pipeline.
void	setGenerator(java.lang.String role, java.lang.String source, org.apache.avalon.framework.parameters.Parameters param, java.lang.Exception e) Same as setGenerator(String, String, Parameters) with an additional Exception parameter.

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

setConsumer

Methods inherited from interface org.apache.avalon.framework.component.Recomposable

recompose

Methods inherited from interface org.apache.avalon.framework.component.Composable

compose

Methods inherited from interface org.apache.avalon.excalibur.pool.Recyclable

recycle

Field Detail

ROLE

public static final java.lang.String ROLE

Method Detail

process

public boolean process(Environment environment)
                throws java.lang.Exception

Process the given Environment, producing the output.

setGenerator

public void setGenerator(java.lang.String role,
                         java.lang.String source,
                         org.apache.avalon.framework.parameters.Parameters param)
                  throws java.lang.Exception

Set the generator that will be used as the initial step in the pipeline. The generator role is given : the actual Generator is fetched from the latest ComponentManager given by compose() or recompose().

Parameters:

role - the generator role in the component manager.

source - the source where to produce XML from, or null if no source is given.

param - the parameters for the generator.

Throws:

java.lang.Exception - if the generator couldn't be obtained.

setGenerator

public void setGenerator(java.lang.String role,
                         java.lang.String source,
                         org.apache.avalon.framework.parameters.Parameters param,
                         java.lang.Exception e)
                  throws java.lang.Exception

Same as setGenerator(String, String, Parameters) with an additional Exception parameter. This is used for setting the special {link org.apache.cocoon.sitemap.ErrorNotifier} generator used to generate input for error pages.

Parameters:

role - the generator role in the component manager.

source - the source where to produce XML from (e.g. xml file), or null if no source is given.

param - the parameters for the generator.

e - the exception to generate.

Throws:

java.lang.Exception - if the generator couldn't be obtained.

See Also:

ErrorNotifier

getGenerator

public Generator getGenerator()

Get the generator used by this pipeline. Access to the generator is needed for content aggregation since the aggregation generator is fed by the pipeline engine with the different parts.

Returns:

the generator

addTransformer

public void addTransformer(java.lang.String role,
                           java.lang.String source,
                           org.apache.avalon.framework.parameters.Parameters param)
                    throws java.lang.Exception

Add a transformer at the end of the pipeline. The transformer role is given : the actual Transformer is fetched from the latest ComponentManager given by compose() or recompose().

Parameters:

role - the transformer role in the component manager.

source - the source used to setup the transformer (e.g. XSL file), or null if no source is given.

param - the parameters for the transfomer.

Throws:

java.lang.Exception - if the generator couldn't be obtained.