org.egothor.store
Class ThickBarrel

java.lang.Object
  org.egothor.store.ThickBarrel

All Implemented Interfaces:

java.lang.Cloneable, Barrel

public class ThickBarrel
extends java.lang.Object
implements Barrel, java.lang.Cloneable

This object is a core implementation of a barrel that has documents meta data stored in DiscIndexData and inverted lists meta data in DiscKeyIndexData. This object defines a barrel that stores its inverted lists in one big file.

Author:

Leo Galambos

Field Summary

java.lang.String

location Directory, where is the barrel stored.

Constructor Summary

ThickBarrel(java.lang.String location)
This constructors open the documents and inverted lists meta data DB files in location directory.

Method Summary

java.lang.Object	clone()
void	close() Closes DB files.
void	commit() Not implemented but required by Barrel.
long	deleted() Returns the number of removed documents (meta data).
void	destroy() This method calls close and then removes all files that this barrel uses.
static void	destroy(java.lang.String location)
Sequence<? extends IListMetadata>	expand(java.lang.String expr) Description of the Method
Bitmap	getBitmap(java.lang.String label) Return the Bitmap of a given label.
IListMetadataRead	getIListMeta(java.lang.String term) Return the inverted list metadata of the given term.
DocumentData	getMeta(long uid) Returns meta data of a given uid document.
long	length() Returns size()-deleted() - the number of active documents.
BarrelReader	open() Return a reader for this Barrel.
IMetaReader	openDocMeta() Description of the Method
IListReader	openIList(java.lang.String term, boolean clean) Description of the Method
void	query(Query q, ResultList result) Solves a query in this barrel.
boolean	removeDoc(long id) Removes the meta data of the id-th document.
void	setBitmap(java.lang.String label, Bitmap value) Try to set the Bitmap of a given label.
void	setLocation(java.lang.String location) Sets the location attribute of the ThickBarrel object
long	size() Returns the total number of documents meta data.

Methods inherited from class java.lang.Object

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

Field Detail

location

public java.lang.String location

Directory, where is the barrel stored.

Constructor Detail

ThickBarrel

public ThickBarrel(java.lang.String location)
            throws java.io.IOException

This constructors open the documents and inverted lists meta data DB files in location directory. Constructs this barrel in the given location directory.

Parameters:

location - Description of the Parameter

Throws:

java.io.IOException - if an I/O error occurs

Method Detail

clone

public java.lang.Object clone()
                       throws java.lang.CloneNotSupportedException

Overrides:

clone in class java.lang.Object

Throws:

java.lang.CloneNotSupportedException

getBitmap

public Bitmap getBitmap(java.lang.String label)

Description copied from interface: Barrel

Return the Bitmap of a given label.

Specified by:

getBitmap in interface Barrel

Parameters:

label - the label of the requested Bitmap

Returns:

Bitmap of removed documents when label is null

setBitmap

public void setBitmap(java.lang.String label,
                      Bitmap value)

Description copied from interface: Barrel

Try to set the Bitmap of a given label.

Specified by:

setBitmap in interface Barrel

Parameters:

label - the label of the requested Bitmap

value - Bitmap of removed documents when label is null

setLocation

public void setLocation(java.lang.String location)
                 throws java.io.IOException

Sets the location attribute of the ThickBarrel object

Parameters:

location - The new location value

Throws:

java.io.IOException - if an I/O error occurs

getMeta

public DocumentData getMeta(long uid)

Returns meta data of a given uid document.

Specified by:

getMeta in interface Barrel

Parameters:

uid - Description of the Parameter

Returns:

The meta value

openDocMeta

public IMetaReader openDocMeta()

Description of the Method

Returns:

Description of the Return Value

getIListMeta

public IListMetadataRead getIListMeta(java.lang.String term)

Description copied from interface: Barrel

Return the inverted list metadata of the given term.

Specified by:

getIListMeta in interface Barrel

Parameters:

term - the term

Returns:

an IListMetaData object containing the metadata of the inverted list, or null if the term is not in the Barrel

openIList

public IListReader openIList(java.lang.String term,
                             boolean clean)

Description of the Method

Specified by:

openIList in interface Barrel

Parameters:

term - Description of the Parameter

clean - whether to remove all the items denoted as deleted

Returns:

Description of the Return Value

expand

public Sequence<? extends IListMetadata> expand(java.lang.String expr)

Description of the Method

Specified by:

expand in interface Barrel

Parameters:

expr - Description of the Parameter

Returns:

Description of the Return Value

destroy

public void destroy()

This method calls close and then removes all files that this barrel uses. Destroys the meta data DB files.

Specified by:

destroy in interface Barrel

destroy

public static void destroy(java.lang.String location)

removeDoc

public boolean removeDoc(long id)

Removes the meta data of the id-th document.

Specified by:

removeDoc in interface Barrel

Parameters:

id - Description of the Parameter

Returns:

Description of the Return Value

size

public long size()

Returns the total number of documents meta data. It does not matter if they are removed or not.

Specified by:

size in interface Barrel

Returns:

Description of the Return Value

deleted

public long deleted()

Returns the number of removed documents (meta data).

Specified by:

deleted in interface Barrel

Returns:

Description of the Return Value

open

public BarrelReader open()

Description copied from interface: Barrel

Return a reader for this Barrel.

Specified by:

open in interface Barrel

Returns:

this

length

public long length()

Returns size()-deleted() - the number of active documents.

Returns:

Description of the Return Value

commit

public void commit()

Not implemented but required by Barrel.

Specified by:

commit in interface Barrel

close

public void close()

Closes DB files.

Specified by:

close in interface Barrel

query

public void query(Query q,
                  ResultList result)

Solves a query in this barrel. The query is parsed by Parser. This method also prepares a hit list object that is passed to a rider object. The rider object is allocated with maximum of ten active open inverted lists to this barrel.

Specified by:

query in interface Barrel

Parameters:

q - Description of the Parameter

result - Description of the Parameter