org.apache.cocoon.reading
Class ResourceReader

java.lang.Object
  org.apache.avalon.framework.logger.AbstractLogEnabled
      org.apache.cocoon.reading.AbstractReader
          org.apache.cocoon.reading.ResourceReader

All Implemented Interfaces:

Poolable, Recyclable, Component, Configurable, LogEnabled, CacheableProcessingComponent, Reader, SitemapModelComponent, SitemapOutputComponent

Direct Known Subclasses:

EventAwareReader, ImageOpReader, ImageReader

public class ResourceReader
extends AbstractReader
implements CacheableProcessingComponent, Configurable

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.

Configuration:

<expires>

This parameter is optional. When specified it determines how long in miliseconds the resources can be cached by any proxy or browser between Cocoon and the requesting visitor. Defaults to -1.

<quick-modified-test>

This parameter is optional. This boolean parameter controls the last modified test. If set to true (default is false), only the last modified of the current source is tested, but not if the same source is used as last time (see http://marc.theaimsgroup.com/?l=xml-cocoon-dev&m=102921894301915 )

<byte-ranges>

This parameter is optional. This boolean parameter controls whether Cocoon should support byterange requests (to allow clients to resume broken/interrupted downloads). Defaults to true.

Default configuration:

   <expires>-1</expires>
   <quick-modified-test>false</quick-modified-test>
   <byte-ranges>true</byte-ranges>
 

In addition to reader configuration, above parameters can be passed to the reader at the time when it is used.

Version:

CVS $Id: ResourceReader.html 1304258 2012-03-23 10:09:27Z ilgrosso $

Author:

Giacomo Pati, Torsten Curdt, Carsten Ziegeler

Field Summary

protected int	bufferSize
protected boolean	byteRanges
protected int	configuredBufferSize
protected boolean	configuredByteRanges
protected long	configuredExpires
protected boolean	configuredQuickTest
protected long	expires
protected Source	inputSource
protected boolean	quickTest
protected Request	request
protected Response	response

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	configure(Configuration configuration) Read reader configuration
void	generate() Generates the requested resource.
Serializable	getKey() Generate the unique key.
long	getLastModified()
String	getMimeType() Returns the mime-type of the resource in process.
SourceValidity	getValidity() Generate the validity object.
protected boolean	hasRanges()
void	parameterize(Parameters parameters)
protected void	processStream(InputStream inputStream)
void	recycle() Recyclable
void	setup(SourceResolver resolver, Map objectModel, String src, Parameters par) Setup the reader.
protected void	setupHeaders() Setup the response headers: Accept-Ranges, Expires

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

setOutputStream, shouldSetContentLength

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

Field Detail

configuredExpires

protected long configuredExpires

configuredQuickTest

protected boolean configuredQuickTest

configuredBufferSize

protected int configuredBufferSize

configuredByteRanges

protected boolean configuredByteRanges

expires

protected long expires

quickTest

protected boolean quickTest

bufferSize

protected int bufferSize

byteRanges

protected boolean byteRanges

response

protected Response response

request

protected Request request

inputSource

protected Source inputSource

Constructor Detail

ResourceReader

public ResourceReader()

Method Detail

configure

public void configure(Configuration configuration)
               throws ConfigurationException

Read reader configuration

Specified by:

configure in interface Configurable

Throws:

ConfigurationException

parameterize

public void parameterize(Parameters parameters)
                  throws ParameterException

Throws:

ParameterException

setup

public void setup(SourceResolver resolver,
                  Map objectModel,
                  String src,
                  Parameters par)
           throws ProcessingException,
                  SAXException,
                  IOException

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

Specified by:

setup in interface SitemapModelComponent

Overrides:

setup in class AbstractReader

Throws:

ProcessingException

SAXException

IOException

setupHeaders

protected void setupHeaders()

Setup the response headers: Accept-Ranges, Expires

recycle

public void recycle()

Recyclable

Specified by:

recycle in interface Recyclable

Overrides:

recycle in class AbstractReader

hasRanges

protected boolean hasRanges()

Returns:

True if byte ranges support is enabled and request has range header.

getKey

public Serializable getKey()

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

Specified by:

getKey in interface CacheableProcessingComponent

Returns:

The generated key hashes the src

getValidity

public SourceValidity getValidity()

Generate the validity object.

Specified by:

getValidity in interface CacheableProcessingComponent

Returns:

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

getLastModified

public long getLastModified()

Specified by:

getLastModified in interface Reader

Overrides:

getLastModified in class AbstractReader

Returns:

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

processStream

protected void processStream(InputStream inputStream)
                      throws IOException,
                             ProcessingException

Throws:

IOException

ProcessingException

generate

public void generate()
              throws IOException,
                     ProcessingException

Generates the requested resource.

Specified by:

generate in interface Reader

Throws:

IOException

ProcessingException

getMimeType

public String getMimeType()

Returns the mime-type of the resource in process.

Specified by:

getMimeType in interface SitemapOutputComponent

Overrides:

getMimeType in class AbstractReader

See Also:

AbstractProcessingPipeline.setMimeTypeForSerializer(org.apache.cocoon.environment.Environment), AbstractProcessingPipeline.setMimeTypeForReader(org.apache.cocoon.environment.Environment)