org.apache.cocoon.reading
Class ResourceReader

java.lang.Object
  |
  +--org.apache.avalon.framework.logger.AbstractLoggable
        |
        +--org.apache.cocoon.reading.AbstractReader
              |
              +--org.apache.cocoon.reading.ResourceReader

All Implemented Interfaces:

Cacheable, org.apache.avalon.framework.component.Component, org.apache.avalon.framework.logger.Loggable, org.apache.avalon.excalibur.pool.Poolable, Reader, org.apache.avalon.excalibur.pool.Recyclable, SitemapModelComponent, SitemapOutputComponent

public class ResourceReader

extends AbstractReader

implements Cacheable

The ResourceReader component is used to serve binary data in a sitemap pipeline. It makes use of HTTP Headers to determine if the requested resource should be written to the OutputStream or if it can signal that it hasn't changed. Parameters:

<expires>

This parameter is optional. When specified it determines how long in miliseconds the resources can be cached by any proxy or browser between Cocoon2 and the requesting visitor.

Version:

CVS $Id: ResourceReader.java,v 1.7.2.2 2002/06/05 01:36:11 vgritsenko Exp $

Author:

Giacomo Pati

Fields inherited from class org.apache.cocoon.reading.AbstractReader

objectModel, out, parameters, resolver, source

Fields inherited from interface org.apache.cocoon.reading.Reader

ROLE

Constructor Summary

ResourceReader()

Method Summary

void	generate() Generates the requested resource.
long	generateKey() Generate the unique key.
CacheValidity	generateValidity() Generate the validity object.
long	getLastModified()
java.lang.String	getMimeType() Returns the mime-type of the resource in process.
void	recycle() Recycle the component
void	setup(SourceResolver resolver, java.util.Map objectModel, java.lang.String src, org.apache.avalon.framework.parameters.Parameters par) Setup the reader.

Methods inherited from class org.apache.cocoon.reading.AbstractReader

setOutputStream, shouldSetContentLength

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

getLogger, setLogger, setupLogger, setupLogger, setupLogger

Methods inherited from class java.lang.Object

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

Constructor Detail

ResourceReader

public ResourceReader()

Method Detail

setup

public void setup(SourceResolver resolver,
                  java.util.Map objectModel,
                  java.lang.String src,
                  org.apache.avalon.framework.parameters.Parameters par)
           throws ProcessingException,
                  org.xml.sax.SAXException,
                  java.io.IOException

Setup the reader. The resource is opened to get an InputStream, the length and the last modification date

Overrides:

setup in class AbstractReader

recycle

public void recycle()

Description copied from class: AbstractReader

Recycle the component

Overrides:

recycle in class AbstractReader

generateKey

public long generateKey()

Generate the unique key. This key must be unique inside the space of this component.

Specified by:

generateKey in interface Cacheable

Returns:

The generated key hashes the src

generateValidity

public CacheValidity generateValidity()

Generate the validity object.

Specified by:

generateValidity in interface Cacheable

Returns:

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

getLastModified

public long getLastModified()

Overrides:

getLastModified in class AbstractReader

Returns:

the time the read source was last modified or 0 if it is not possible to detect

generate

public void generate()
              throws java.io.IOException,
                     ProcessingException

Generates the requested resource.

getMimeType

public java.lang.String getMimeType()

Returns the mime-type of the resource in process.

Overrides:

getMimeType in class AbstractReader