org.axiondb
Interface RowIterator

All Known Subinterfaces:

JoinedRowIterator, MutableIndexedRowIterator

All Known Implementing Classes:

AbstractAcceptingRowIterator, AbstractFilteringRowIterator, AbstractJoinedRowIterator, BaseRowIterator, ChainedRowIterator, ChangingIndexedRowIterator, CollatingRowIterator, DelegatingRowIterator, DistinctRowIterator, EmptyRowIterator, FilteringChangingIndexedRowIterator, FilteringRowIterator, GroupedRowIterator, IndexNestedLoopJoinedRowIterator, JoinRowIterator, LazyRowRowIterator, LimitingRowIterator, ListIteratorRowIterator, ListRowIterator, NestedLoopJoinedRowIterator, RebindableIndexedRowIterator, ReverseSortedRowIterator, RowViewRowIterator, SingleRowIterator, SortedRowIterator, SortedRowIterator.MergeSort, SortedRowIterator.MutableMergeSort, TransformingRowIterator, UnmodifiableRowIterator

public interface RowIterator

A bidirectional iterator over a collection of Rows.

Version:

$Revision: 1.12 $ $Date: 2005/04/22 02:28:53 $

Method Summary

void	add(Row row) Add a Rowat the current position in my underlying collection, or throw UnsupportedOperationException.
Row	current() Returns the last Rowreturned by me (by next(),previous(), first(),last(), etc.).
int	currentIndex() Returns the index of the current()row, if any.
Row	first() Returns the first Rowin the list, positioning the cursor to just before the first Rowin the list.
boolean	hasCurrent() Returns true if I have a current Row.
boolean	hasNext() Returns true if I have more Rows when traversing the list in the forward direction.
boolean	hasPrevious() Returns true if I have more Rows when traversing the list in the reverse direction.
boolean	isEmpty() Returns true if there are no rows to report with this iterator.
Row	last() Returns the last Rowin the list, positioning the cursor to just after the last Rowin the list.
Row	next() Returns the next Rowin the list, or throws NoSuchElementExceptionif no next Row exists.
int	next(int count) Sets the current iterator position to currentIndex() + count; this will not set the current row, peekPrevious() may be used to return the current row.
int	nextIndex() Returns the index of the next()row, if any, or the number of elements is the iterator if we've reached the end.
Row	peekNext() Return the value that would be returned by a call to next(), if any, but don't update my position.
Row	peekPrevious() Return the value that would be returned by a call to previous(), if any, but don't update my position.
Row	previous() Returns the previous Rowin the list, or throws NoSuchElementExceptionif no next Row exists.
int	previous(int count) Sets the current iterator position to currentIndex() - count; this will not set the current row, peekNext() may be used to return the current row.
int	previousIndex() Returns the index of the previous()row, if any, or -1 if we're add the beginning of the list.
void	remove() Set the Rowat the current position in my underlying collection, or throw UnsupportedOperationException.
void	reset() Re-initialize this RowIterator to its initial state (positioned just before the first Rowin the list).
void	set(Row row) Set the Rowat the current position in my underlying collection, or throw UnsupportedOperationException.
int	size() Retunrs the current size of the underlaying row collection

Method Detail

add

void add(Row row)
         throws java.lang.UnsupportedOperationException,
                AxionException

Add a Rowat the current position in my underlying collection, or throw UnsupportedOperationException. (Optional operation.)

Throws:

java.lang.UnsupportedOperationException

AxionException

current

Row current()
            throws java.util.NoSuchElementException

Returns the last Rowreturned by me (by next(),previous(), first(),last(), etc.).

Throws:

java.util.NoSuchElementException - when no Rowhas yet been returned

currentIndex

int currentIndex()
                 throws java.util.NoSuchElementException

Returns the index of the current()row, if any.

Throws:

java.util.NoSuchElementException - when no Rowhas yet been returned

first

Row first()
          throws java.util.NoSuchElementException,
                 AxionException

Returns the first Rowin the list, positioning the cursor to just before the first Rowin the list. (In other words, after first is called both next()and current()will return the first row in the list.)

Throws:

java.util.NoSuchElementException - when there is no first Row

AxionException - when a problem occurs accessing the Row

hasCurrent

boolean hasCurrent()

Returns true if I have a current Row. (In other words, returns true iff current()would return a Rowrather than throwing an exception.)

hasNext

boolean hasNext()

Returns true if I have more Rows when traversing the list in the forward direction. (In other words, returns true iff next()would return a Rowrather than throwing an exception.)

hasPrevious

boolean hasPrevious()

Returns true if I have more Rows when traversing the list in the reverse direction. (In other words, returns true iff previous()would return a Rowrather than throwing an exception.)

isEmpty

boolean isEmpty()

Returns true if there are no rows to report with this iterator.

last

Row last()
         throws java.util.NoSuchElementException,
                AxionException

Returns the last Rowin the list, positioning the cursor to just after the last Rowin the list. (In other words, after last is called both previous()and current()will return the last row in the list.)

Throws:

java.util.NoSuchElementException - when there is no last Row

AxionException - when a problem occurs accessing the Row

next

Row next()
         throws java.util.NoSuchElementException,
                AxionException

Returns the next Rowin the list, or throws NoSuchElementExceptionif no next Row exists.

Throws:

java.util.NoSuchElementException - when there is no next Row

AxionException - when a problem occurs accessing the Row

next

int next(int count)
         throws AxionException

Sets the current iterator position to currentIndex() + count; this will not set the current row, peekPrevious() may be used to return the current row. This will provide random access e.g one can postion the cursor before the desired row and then call next().

Throws:

AxionException

nextIndex

int nextIndex()

Returns the index of the next()row, if any, or the number of elements is the iterator if we've reached the end.

peekNext

Row peekNext()
             throws java.util.NoSuchElementException,
                    AxionException

Return the value that would be returned by a call to next(), if any, but don't update my position.

Throws:

java.util.NoSuchElementException - when there is no next Row

AxionException - when a problem occurs accessing the Row

peekPrevious

Row peekPrevious()
                 throws java.util.NoSuchElementException,
                        AxionException

Return the value that would be returned by a call to previous(), if any, but don't update my position.

Throws:

java.util.NoSuchElementException - when there is no previous Row

AxionException - when a problem occurs accessing the Row

previous

Row previous()
             throws java.util.NoSuchElementException,
                    AxionException

Returns the previous Rowin the list, or throws NoSuchElementExceptionif no next Row exists.

Throws:

java.util.NoSuchElementException - when there is no next Row

AxionException - when a problem occurs accessing the Row

previous

int previous(int count)
             throws AxionException

Sets the current iterator position to currentIndex() - count; this will not set the current row, peekNext() may be used to return the current row. This will provide random access e.g one can postion the cursor after the desired row and then call previous().

Throws:

AxionException

previousIndex

int previousIndex()

Returns the index of the previous()row, if any, or -1 if we're add the beginning of the list.

remove

void remove()
            throws java.lang.UnsupportedOperationException,
                   AxionException

Set the Rowat the current position in my underlying collection, or throw UnsupportedOperationException. (Optional operation.)

Throws:

java.lang.UnsupportedOperationException

AxionException

reset

void reset()
           throws AxionException

Re-initialize this RowIterator to its initial state (positioned just before the first Rowin the list).

Throws:

AxionException

set

void set(Row row)
         throws java.lang.UnsupportedOperationException,
                AxionException

Set the Rowat the current position in my underlying collection, or throw UnsupportedOperationException. (Optional operation.)

Throws:

java.lang.UnsupportedOperationException

AxionException

size

int size()
         throws AxionException

Retunrs the current size of the underlaying row collection

Throws:

AxionException