de.unidu.is.retrieval.pire
Class PDatalogIR

java.lang.Object
  de.unidu.is.retrieval.AbstractRetriever
      de.unidu.is.retrieval.pire.PDatalogIR

All Implemented Interfaces:

IR, MomentsIR, Retriever

public class PDatalogIR

extends AbstractRetriever

implements MomentsIR

An IR interface (for XML documents) to PIRE (using probabilistic Datalog).

PIRE only deals with flat documents, but that is sufficient for the IR specification. Datatype and operator names are automatically converted into the PIRE versions.

Currently, only wsum queries are supported.

Since:

2004-01-03

Version:

$Revision: 1.20 $, $Date: 2005/03/14 17:33:14 $

Author:

Henrik Nottelmann

Constructor Summary

PDatalogIR(DB db, java.lang.String collectionName)
Creates a new instance, which does not store added documents on disc.

PDatalogIR(DB db, java.lang.String collectionName, java.lang.String docDir)
Creates a new instance, which stores added documents on disc.

Method Summary

void	addToIndex(java.lang.String docID, org.w3c.dom.Document document) Add the XML document to the index.
void	addToIndex(java.lang.String docID, java.lang.String document) Add the XML document to the index.
void	close() Closes the retriever, and optionally frees used system resources (e.g.
void	computeIndex() Computes the index, based on the document values which were added before.
void	computeMoments() Computes the moments of the indexing weights.
org.w3c.dom.Document	getDocument(ProbDoc doc) Returns the full XML document
org.w3c.dom.Document	getDocument(java.lang.String docID) Returns the full XML document
Moments	getMoments(Query query) Returns the expectation and the variance of the RSVs for the specified query.
PIRE	getPIRE() Returns the PIRE object used internally.
double	getRD(java.lang.String attName, java.lang.String operator, java.lang.String key) Returns the value corresponding to the specified key in the resource description (the rd relation), e.g. for defining the parameters of the mapping function.
java.util.List	getResult(Query query) Returns result for the specified query.
void	initIndex() Inits the index.
void	registerSchema(Schema schema) Registers the specified schema.
void	removeIndex() Removes the index.
void	setRD(java.lang.String attName, java.lang.String operator, java.lang.String key, double value) Sets the value corresponding to the specified key in the resource description (the rd relation), e.g. for defining the parameters of the mapping function.

Methods inherited from class de.unidu.is.retrieval.AbstractRetriever

getDocuments, getResultSummaries, getSchema, getSummaries, getSummary, getSummary

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.unidu.is.retrieval.Retriever

getDocuments, getResultSummaries, getSchema, getSummaries, getSummary, getSummary

Constructor Detail

PDatalogIR

public PDatalogIR(DB db,
                  java.lang.String collectionName)

Creates a new instance, which does not store added documents on disc.

Parameters:

db - database

collectionName - name of the collection

PDatalogIR

public PDatalogIR(DB db,
                  java.lang.String collectionName,
                  java.lang.String docDir)

Creates a new instance, which stores added documents on disc.

Parameters:

db - database

collectionName - name of the collection

docDir - directory for added documents

Method Detail

registerSchema

public void registerSchema(Schema schema)

Registers the specified schema.

Specified by:

registerSchema in interface IR

Parameters:

schema - collection schema

See Also:

IR.registerSchema(de.unidu.is.retrieval.Schema)

initIndex

public void initIndex()
               throws IndexException

Inits the index.

Specified by:

initIndex in interface IR

Throws:

IndexException

See Also:

IR.initIndex()

addToIndex

public void addToIndex(java.lang.String docID,
                       org.w3c.dom.Document document)
                throws DocumentMismatchException,
                       DocumentNotStorableException

Add the XML document to the index.

If a directory was specified in the constructor, then the document is also stored in that directory.

Specified by:

addToIndex in interface IR

Parameters:

docID - document id

document - XML document

Throws:

DocumentMismatchException

DocumentNotStorableException

See Also:

IR.addToIndex(java.lang.String, org.w3c.dom.Document)

addToIndex

public void addToIndex(java.lang.String docID,
                       java.lang.String document)
                throws DocumentMismatchException,
                       DocumentNotStorableException

Add the XML document to the index.

If a directory was specified in the constructor, then the document is also stored in that directory.

Specified by:

addToIndex in interface IR

Parameters:

docID - document id

document - XML document

Throws:

DocumentMismatchException

DocumentNotStorableException

See Also:

IR.addToIndex(java.lang.String, java.lang.String)

computeIndex

public void computeIndex()
                  throws IndexException

Computes the index, based on the document values which were added before.

Specified by:

computeIndex in interface IR

Throws:

IndexException

See Also:

IR.computeIndex()

computeMoments

public void computeMoments()
                    throws IndexException

Computes the moments of the indexing weights.

Specified by:

computeMoments in interface MomentsIR

Throws:

IndexException

removeIndex

public void removeIndex()
                 throws IndexException

Removes the index.

Specified by:

removeIndex in interface IR

Throws:

IndexException

getResult

public java.util.List getResult(Query query)
                         throws UnsupportedQueryException

Returns result for the specified query.

Currently, only wsum queries are supported.

Specified by:

getResult in interface Retriever

Parameters:

query - XIRQL query

Returns:

list of ProbDoc instances

Throws:

UnsupportedQueryException

See Also:

Retriever.getResult(de.unidu.is.retrieval.Query)

getDocument

public org.w3c.dom.Document getDocument(java.lang.String docID)
                                 throws DocumentNotFoundException

Returns the full XML document

Specified by:

getDocument in interface Retriever

Parameters:

docID - document id

Returns:

full XML document, or null if it does not exist

Throws:

DocumentNotFoundException

See Also:

Retriever.getDocument(java.lang.String)

getDocument

public org.w3c.dom.Document getDocument(ProbDoc doc)
                                 throws DocumentNotFoundException

Returns the full XML document

Specified by:

getDocument in interface Retriever

Overrides:

getDocument in class AbstractRetriever

Parameters:

doc - document descriptor

Returns:

full XML document, or null if it does not exist

Throws:

DocumentNotFoundException

See Also:

Retriever.getDocument(de.unidu.is.retrieval.ProbDoc)

getMoments

public Moments getMoments(Query query)
                   throws UnsupportedQueryException

Returns the expectation and the variance of the RSVs for the specified query.

Currently, only wsum queries are supported.

Parameters:

query - XIRQL query

Returns:

moments (expectation and variance) or null, if not supported

Throws:

UnsupportedQueryException

getRD

public double getRD(java.lang.String attName,
                    java.lang.String operator,
                    java.lang.String key)

Returns the value corresponding to the specified key in the resource description (the rd relation), e.g. for defining the parameters of the mapping function.

Parameters:

attName - attribute name

operator - operator name

key - value key

Returns:

value

setRD

public void setRD(java.lang.String attName,
                  java.lang.String operator,
                  java.lang.String key,
                  double value)

Sets the value corresponding to the specified key in the resource description (the rd relation), e.g. for defining the parameters of the mapping function.

Parameters:

attName - attribute name

operator - operator name

key - value key

value - value

getPIRE

public PIRE getPIRE()

Returns the PIRE object used internally.

close

public void close()

Closes the retriever, and optionally frees used system resources (e.g. closes a network connection).

Specified by:

close in interface Retriever

Overrides:

close in class AbstractRetriever

See Also:

Retriever.close()