org.objectweb.medor.eval.lib
Class UnnestEvaluatedTC

java.lang.Object
  org.objectweb.medor.eval.lib.UnnestEvaluatedTC

All Implemented Interfaces:

TupleCollection

public class UnnestEvaluatedTC

extends java.lang.Object

implements TupleCollection

This class represent a TupleCollection Result of the Unnest Operation. We don't store buffers in this operation because all Tuples of the sub TupleCollection will be in this TupleCollection, there no filtering.

Constructor Summary

UnnestEvaluatedTC(UnnestQueryNode unnestQueryTree, NodeEvaluator subNodeEvaluator, ParameterOperand[] parameters)

Method Summary

int	card()
void	close() It closes the TupleCollection, relaeases used resources (example : ResultSet).
void	first() Moves the cursor to the first Tuple, row number 1.
TupleStructure	getMetaData() It contains metadata of fields wich will be projected
int	getRow() Retrieves the current row Number.
Tuple	getTuple() Returns the Tuple value of the current row of this TupleCollection object.
Tuple	getTuple(int numTuple) Returns the Tuple value of the designeted row of this TupleCollection object.
boolean	isEmpty() Tell whether the current TupleCollection Object is empty or no.
boolean	isLast() Indicates whether the cursor is on the last row of this TupleCollection object.
boolean	next() Moves the cursor down one row from its current position to the next tuple of this TupleCollection object.
boolean	row(int row) Moves the cursor to the given row number in this TupleCollection object.

Methods inherited from class java.lang.Object

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

Constructor Detail

UnnestEvaluatedTC

public UnnestEvaluatedTC(UnnestQueryNode unnestQueryTree,
                         NodeEvaluator subNodeEvaluator,
                         ParameterOperand[] parameters)
                  throws MedorException

Method Detail

close

public void close()
           throws MedorException

Description copied from interface: TupleCollection

It closes the TupleCollection, relaeases used resources (example : ResultSet). The next uses of the TupleCollection will throw an exception.

Specified by:

close in interface TupleCollection

Throws:

MedorException

getMetaData

public TupleStructure getMetaData()
                           throws MedorException

It contains metadata of fields wich will be projected

Specified by:

getMetaData in interface TupleCollection

Returns:

a TupleCollectionMetaData Object defining teh TupleCollection.

Throws:

MedorException - if a data source access error occurs

isLast

public boolean isLast()
               throws MedorException

Description copied from interface: TupleCollection

Indicates whether the cursor is on the last row of this TupleCollection object.

Specified by:

isLast in interface TupleCollection

Returns:

true if the current Tuple is the last one or if the TupleCollection is Empty.

Throws:

MedorException - if data source access error

next

public boolean next()
             throws MedorException

Description copied from interface: TupleCollection

Moves the cursor down one row from its current position to the next tuple of this TupleCollection object.

Specified by:

next in interface TupleCollection

Returns:

true if move is impossible and false if move is not performed.

Throws:

MedorException - if data source access error

first

public void first()
           throws MedorException

Description copied from interface: TupleCollection

Moves the cursor to the first Tuple, row number 1.

Specified by:

first in interface TupleCollection

Throws:

MedorException - if data source access error

getRow

public int getRow()
           throws MedorException

Description copied from interface: TupleCollection

Retrieves the current row Number.

Specified by:

getRow in interface TupleCollection

Returns:

-1 if the iterator is out of bounds of the TupleCollection or if it is empty.

Throws:

MedorException - if data source access error.

getTuple

public Tuple getTuple()
               throws MedorException

Description copied from interface: TupleCollection

Returns the Tuple value of the current row of this TupleCollection object.

Specified by:

getTuple in interface TupleCollection

Returns:

the value of the current Tuple.

Throws:

MedorException - if data source access error.

getTuple

public Tuple getTuple(int numTuple)
               throws MedorException

Description copied from interface: TupleCollection

Returns the Tuple value of the designeted row of this TupleCollection object.

Specified by:

getTuple in interface TupleCollection

Parameters:

numTuple - :int

Returns:

the a Tuple Number row.

Throws:

MedorException - if data source access error.

row

public boolean row(int row)
            throws MedorException

Description copied from interface: TupleCollection

Moves the cursor to the given row number in this TupleCollection object. The first row is row 1, the second is row 2, and so on.

Specified by:

row in interface TupleCollection

Returns:

true if move is possible

Throws:

MedorException - if row number is invelid or data source access error

card

public int card()
         throws MedorException

Throws:

MedorException

isEmpty

public boolean isEmpty()
                throws MedorException

Description copied from interface: TupleCollection

Tell whether the current TupleCollection Object is empty or no.

Specified by:

isEmpty in interface TupleCollection

Returns:

true if the TupleCollection is empty.

Throws:

MedorException - if data source access error.