org.semanticdesktop.aperture.subcrawler.mime
Class MimeSubCrawler

java.lang.Object
  org.semanticdesktop.aperture.subcrawler.base.AbstractSubCrawler
      org.semanticdesktop.aperture.subcrawler.mime.MimeSubCrawler

All Implemented Interfaces:

DataObjectFactory.PartStreamFactory, SubCrawler

public class MimeSubCrawler
extends AbstractSubCrawler
implements DataObjectFactory.PartStreamFactory

A SubCrawer implementation for message/rfc822-style messages.

It is basically a thin wrapper around the DataObjectFactory.

Constructor Summary

MimeSubCrawler()

Method Summary

MessageDataObject	createDataObject(URI dataObjectId, DataSource dataSource, RDFContainer metadata, javax.mail.internet.MimeMessage msg) Creates a message data object for the given parameters
DataObject	getDataObject(URI parentUri, String path, InputStream stream, DataSource dataSource, Charset charset, String mimeType, RDFContainerFactory factory) Get a DataObject from the specified stream with the given path.
javax.mail.internet.MimeMessage	getLastMimeMessage() Returns the last MimeMessage that was created internally by the subCrawl method.
InputStream	getPartStream(javax.mail.Part part) Returns an input stream with the part content.
String	getUriPrefix() Returns the prefix used when generating uris.
void	stopSubCrawler() Stops a running crawl as fast as possible.
void	subCrawl(URI id, InputStream stream, SubCrawlerHandler handler, DataSource dataSource, AccessData accessData, Charset charset, String mimeType, RDFContainer parentMetadata) Starts crawling the given stream and to report the encountered DataObjects to the given SubCrawlerHandler.

Methods inherited from class org.semanticdesktop.aperture.subcrawler.base.AbstractSubCrawler

createChildUri

Methods inherited from class java.lang.Object

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

Constructor Detail

MimeSubCrawler

public MimeSubCrawler()

Method Detail

subCrawl

public void subCrawl(URI id,
                     InputStream stream,
                     SubCrawlerHandler handler,
                     DataSource dataSource,
                     AccessData accessData,
                     Charset charset,
                     String mimeType,
                     RDFContainer parentMetadata)
              throws SubCrawlerException

Description copied from interface: SubCrawler

Starts crawling the given stream and to report the encountered DataObjects to the given SubCrawlerHandler. If an AccessData instance is passed, it is used to check if the data objects are to be reported as new, modified, or unmodified. Note that the SubCrawler will not report deleted objects.

Specified by:

subCrawl in interface SubCrawler

Parameters:

id - the URI identifying the object (e.g. a file or web page) from which the stream was obtained. This URI is treated as the URI of the parent object, all objects encountered in the stream are considered to be contained within the parent object. (optional, the implementation may use this uri or the one returned from the RDFContainer.getDescribedUri() method of the parentMetadata)

stream - the stream to be crawled. (obligatory)

handler - The crawler handler that is to receive the notifications from the SubCrawler (obligatory)

dataSource - the data source that will be returned by the DataObject.getDataSource() method of the returned data objects. Some implementations may require that this reference is not null and that it contains some particular information

accessData - the AccessData used to determine if the encountered objects are to be returned as new, modified, unmodified or deleted. Information about new or modified objects is stored within for use in future crawls. This parameter may be null if this functionality is not desired, in which case all DataObjects will be reported as new. (optional)

charset - the charset in which the input stream is encoded (optional).

mimeType - the MIME type of the passed stream (optional).

parentMetadata - The 'parent' RDFContainer, that will contain the metadata about the top-level entity in the stream. A SubCrawler may (in some cases) limit itself to augmenting the metadata in this RDFContainer without delivering any additional DataObjects. (obligatory)

Throws:

SubCrawlerException - if any of the obligatory parameters is null or if any error during the crawling process occured

stopSubCrawler

public void stopSubCrawler()

Description copied from interface: SubCrawler

Stops a running crawl as fast as possible. This method may return before the crawling has actually stopped.

Specified by:

stopSubCrawler in interface SubCrawler

getLastMimeMessage

public javax.mail.internet.MimeMessage getLastMimeMessage()

Returns the last MimeMessage that was created internally by the subCrawl method.

getDataObject

public DataObject getDataObject(URI parentUri,
                                String path,
                                InputStream stream,
                                DataSource dataSource,
                                Charset charset,
                                String mimeType,
                                RDFContainerFactory factory)
                         throws SubCrawlerException,
                                PathNotFoundException

Description copied from interface: SubCrawler

Get a DataObject from the specified stream with the given path.

Specified by:

getDataObject in interface SubCrawler

Overrides:

getDataObject in class AbstractSubCrawler

Parameters:

parentUri - the URI of the parent object where the path will be looked for

path - the path of the requested resource

stream - the stream that contains the resource

dataSource - data source that will be returned by the DataObject.getDataSource() method of the returned data object. Some implementations may require that this reference is not null and that it contains some particular information

charset - the charset in which the input stream is encoded (optional).

mimeType - the MIME type of the passed stream (optional).

factory - An RDFContainerFactory that delivers the RDFContainer to which the metadata of the DataObject should be added. The provided RDFContainer can later be retrieved as the DataObject's metadata container.

Returns:

The DataObject extracted from the given stream with the given path

Throws:

SubCrawlerException - if any I/O error occurs

PathNotFoundException - if the requested path is not found

getUriPrefix

public String getUriPrefix()

Description copied from class: AbstractSubCrawler

Returns the prefix used when generating uris. See the documentation for SubCrawler class for more details.

Specified by:

getUriPrefix in class AbstractSubCrawler

Returns:

the prefix used when generating uris.

getPartStream

public InputStream getPartStream(javax.mail.Part part)
                          throws javax.mail.MessagingException,
                                 IOException

Description copied from interface: DataObjectFactory.PartStreamFactory

Returns an input stream with the part content. It's conceptually a wrapper around the Part.getInputStream() method, designed to allow for customization of the returned input stream.

Specified by:

getPartStream in interface DataObjectFactory.PartStreamFactory

Returns:

an InputStream with the content of the part

Throws:

javax.mail.MessagingException

IOException

createDataObject

public MessageDataObject createDataObject(URI dataObjectId,
                                          DataSource dataSource,
                                          RDFContainer metadata,
                                          javax.mail.internet.MimeMessage msg)
                                   throws javax.mail.MessagingException

Description copied from interface: DataObjectFactory.PartStreamFactory

Creates a message data object for the given parameters

Specified by:

createDataObject in interface DataObjectFactory.PartStreamFactory

Returns:

a message data object for the given parameters

Throws:

javax.mail.MessagingException