de.fuberlin.wiwiss.marbles.loading
Class CacheController

java.lang.Object
  de.fuberlin.wiwiss.marbles.loading.CacheController

public class CacheController
extends java.lang.Object

Implements caching of data retrieved from HTTP URLs using a Sesame repository Uses HTTP in RDF namespace, but currently does not follow the ontology as this would require deeper nesting with b-nodes, which is an overcomplication for the current use cases

Author:

Christian Becker

See Also:

http://www.w3.org/TR/HTTP-in-RDF/

Constructor Summary

CacheController(org.openrdf.repository.sail.SailRepository dataRepository, org.openrdf.repository.sail.SailRepository metaDataRepository)
Constructs a new CacheController

Method Summary

void	addURLData(java.lang.String url, org.openrdf.model.Graph data, org.apache.commons.httpclient.HttpMethod method) Adds retrieved URL data to the cache
org.apache.commons.httpclient.Header	getCachedHeaderData(org.openrdf.repository.RepositoryConnection metaDataConn, org.openrdf.model.Resource mainResource, java.lang.String headerField) Retrieves a cached response header field from the metadata cache
org.apache.commons.httpclient.Header	getCachedHeaderData(org.openrdf.repository.RepositoryConnection metaDataConn, java.lang.String url, java.lang.String headerField) Retrieves a cached response header field from the metadata cache
java.lang.String	getCachedHeaderDataValue(org.openrdf.repository.RepositoryConnection metaDataConn, org.openrdf.model.Resource mainResource, java.lang.String headerField) Retrieves the value of a cached response header field from the metadata cache
java.lang.String	getCachedHeaderDataValue(org.openrdf.repository.RepositoryConnection metaDataConn, java.lang.String url, java.lang.String headerField) Retrieves the value of a cached response header field from the metadata cache
java.lang.String	getCachedRedirect(java.lang.String uri) Provides redirection targets from the cache
org.openrdf.repository.Repository	getDataRepository()
org.openrdf.repository.Repository	getMetaDataRepository()
boolean	hasURLData(java.lang.String url) Determines whether the cache holds a valid copy of an URL's data
void	removeData(java.lang.String url) Removes data for a given URL

Methods inherited from class java.lang.Object

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

Constructor Detail

CacheController

public CacheController(org.openrdf.repository.sail.SailRepository dataRepository,
                       org.openrdf.repository.sail.SailRepository metaDataRepository)

Constructs a new CacheController

Parameters:

dataRepository -

metaDataRepository -

Method Detail

removeData

public void removeData(java.lang.String url)

Removes data for a given URL

Parameters:

url - The URL whose data is to be removed

addURLData

public void addURLData(java.lang.String url,
                       org.openrdf.model.Graph data,
                       org.apache.commons.httpclient.HttpMethod method)

Adds retrieved URL data to the cache

Parameters:

url - The URL that was retrieved

data - The retrieved data

method - Used to obtain metadata

hasURLData

public boolean hasURLData(java.lang.String url)

Determines whether the cache holds a valid copy of an URL's data

Parameters:

url - The URL of interest

Returns:

true, if a valid copy is present

getCachedRedirect

public java.lang.String getCachedRedirect(java.lang.String uri)

Provides redirection targets from the cache

Parameters:

uri - The URI of interest

Returns:

The redirection target, or null if there is none

getCachedHeaderData

public org.apache.commons.httpclient.Header getCachedHeaderData(org.openrdf.repository.RepositoryConnection metaDataConn,
                                                                org.openrdf.model.Resource mainResource,
                                                                java.lang.String headerField)
                                                         throws org.openrdf.repository.RepositoryException

Retrieves a cached response header field from the metadata cache

Parameters:

metaDataConn - A connection to the metadata repository

mainResource - The resource of interest

headerField - The header field of interest

Returns:

Header data

Throws:

org.openrdf.repository.RepositoryException

getCachedHeaderData

public org.apache.commons.httpclient.Header getCachedHeaderData(org.openrdf.repository.RepositoryConnection metaDataConn,
                                                                java.lang.String url,
                                                                java.lang.String headerField)
                                                         throws org.openrdf.repository.RepositoryException

Retrieves a cached response header field from the metadata cache

Parameters:

metaDataConn - A connection to the metadata repository

url - The resource of interest

headerField - The header field of interest

Returns:

Header data

Throws:

org.openrdf.repository.RepositoryException

getCachedHeaderDataValue

public java.lang.String getCachedHeaderDataValue(org.openrdf.repository.RepositoryConnection metaDataConn,
                                                 org.openrdf.model.Resource mainResource,
                                                 java.lang.String headerField)
                                          throws org.openrdf.repository.RepositoryException

Retrieves the value of a cached response header field from the metadata cache

Parameters:

metaDataConn - A connection to the metadata repository

mainResource - The resource of interest

headerField - The header field of interest

Returns:

Header data

Throws:

org.openrdf.repository.RepositoryException

getCachedHeaderDataValue

public java.lang.String getCachedHeaderDataValue(org.openrdf.repository.RepositoryConnection metaDataConn,
                                                 java.lang.String url,
                                                 java.lang.String headerField)
                                          throws org.openrdf.repository.RepositoryException

Retrieves the value of a cached response header field from the metadata cache

Parameters:

metaDataConn - A connection to the metadata repository

url - The resource of interest

headerField - The header field of interest

Returns:

Header data

Throws:

org.openrdf.repository.RepositoryException

getDataRepository

public org.openrdf.repository.Repository getDataRepository()

Returns:

The repository that holds retrieved data using URLs as graphs (contexts)

getMetaDataRepository

public org.openrdf.repository.Repository getMetaDataRepository()

Returns:

The repository that holds metadata about the contents of the dataRepository