Package com.semedy.reasoner.edb.persistentstore

Class TupleFile

java.lang.Object

com.semedy.reasoner.edb.persistentstore.TupleFile

All Implemented Interfaces:

Closeable, AutoCloseable

public class TupleFile
extends Object
implements Closeable

a tuple file is a flat binary file containing all tuples in a sequence.
It stores added tuples in a redundant way as they are already stored in the bplus tree
It gets invalidated as soon as tuples are removed

Author:

juergen

Constructor Summary

Constructors

Constructor	Description
TupleFile(FileName filename)
TupleFile(File file, int arity)
TupleFile(String path, int arity)

Method Summary

Modifier and Type	Method	Description
void	close()	close tuple file
void	create()	Create a tuple file.
void	create(String filepath)	Create a tuple file.
void	createOrAppend()	Open existing tuple file for appending tuples or create new one.
void	delete()	delete tuple file
TupleEnumerator	elements()	Return an enumerator for the tuples.
Iterator<byte[]>	elementsAsBytes()	Return an enumerator for the tuples.
long	fileLength()	length of the file
void	flush()	flush the tuple file
int	getArity()
FileName	getFileName()	get the file name
String	getPath()	get path of the tuple file
boolean	isEmpty()	Is the tuple file empty, i.e. contains no tuples.
boolean	isValid()	is tuple file valid
boolean	open()	Open an existing tuple file.
void	setValid(boolean valid)	set valid state fo tuple file
void	sortElements(ExternalSortTuplesConsumer consumer, String tempDir)	Sort the tuples.
void	sortElements(String tempDir)	Sort elements in tuple file.
void	sortElementsIndexed(ExternalSortTuplesConsumer consumer, int[] indexedPositions, String tempDir)	Sort elements according to the indexed positions.
String	toString()
void	union(TupleFile T)	add all tuples from T into this
void	write(byte[] tuple)	append tuple (as bytes) to tuple file
void	write(long[] tuple)	append tuple (as longs) to tuple file
void	write(TupleBuffer tuple)	append tuple (as tuple buffer) to tuple file

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

TupleFile

public TupleFile(FileName filename)

TupleFile

public TupleFile(String path,
 int arity)

TupleFile

public TupleFile(File file,
 int arity)

Method Details

getArity

public int getArity()

getPath

public String getPath()

get path of the tuple file

Returns:

getFileName

public FileName getFileName()

get the file name

Returns:

fileLength

public long fileLength()

length of the file

Returns:

close

public void close()
           throws IOException

close tuple file

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException

isValid

public boolean isValid()

is tuple file valid

Returns:

flush

public void flush()
           throws IOException

flush the tuple file

Throws:

IOException

setValid

public void setValid(boolean valid)
              throws IOException

set valid state fo tuple file

Parameters:

valid -

Throws:

IOException

write

public void write(byte[] tuple)
           throws IOException

append tuple (as bytes) to tuple file

Parameters:

tuple -

Throws:

IOException

write

public void write(long[] tuple)
           throws IOException

append tuple (as longs) to tuple file

Parameters:

tuple -

Throws:

IOException

write

public void write(TupleBuffer tuple)
           throws IOException

append tuple (as tuple buffer) to tuple file

Parameters:

tuple -

Throws:

IOException

delete

public void delete()
            throws IOException

delete tuple file

Throws:

IOException

create

public void create()
            throws IOException

Create a tuple file.
Must be called after constructor to really create a file.

Throws:

IOException

create

public void create(String filepath)
            throws IOException

Create a tuple file.
Must be called after constructor to really create a file.

Throws:

IOException

open

public boolean open()
             throws IOException

Open an existing tuple file.

Returns:

Throws:

IOException

createOrAppend

public void createOrAppend()
                    throws IOException

Open existing tuple file for appending tuples or create new one.

Throws:

IOException

isEmpty

public boolean isEmpty()
                throws IOException,
EDBException

Is the tuple file empty, i.e. contains no tuples.

Returns:

Throws:

IOException

EDBException

elements

public TupleEnumerator elements()
                         throws IOException

Return an enumerator for the tuples.

Returns:

Throws:

IOException

elementsAsBytes

public Iterator<byte[]> elementsAsBytes()
                                 throws IOException

Return an enumerator for the tuples.
It enumerates the tuples as byte vectors.

Returns:

Throws:

IOException

sortElements

public void sortElements(ExternalSortTuplesConsumer consumer,
 String tempDir)
                  throws IOException,
EDBException

Sort the tuples.
The consumer receives the single tuples in sorted order.

Parameters:

consumer -

tempDir -

Throws:

IOException

EDBException

sortElements

public void sortElements(String tempDir)
                  throws IOException,
EDBException

Sort elements in tuple file.

Parameters:

tempDir -

Throws:

IOException

EDBException

sortElementsIndexed

public void sortElementsIndexed(ExternalSortTuplesConsumer consumer,
 int[] indexedPositions,
 String tempDir)
                         throws IOException,
EDBException

Sort elements according to the indexed positions.
The consumer receives the tuples in this sequence.

Parameters:

consumer -

indexedPositions -

tempDir -

Throws:

IOException

EDBException

toString

public String toString()

Overrides:

toString in class Object

union

public void union(TupleFile T)
           throws IOException,
EDBException

add all tuples from T into this

Parameters:

T - , tuples to add

Throws:

IOException

EDBException