E - public class ChunkConsumerIterator<E> extends Object implements IChunkedOrderedIterator<E>
E[]s (a buffer of chunks) with
an IChunkedOrderedIterator.| Modifier and Type | Field and Description |
|---|---|
protected static boolean |
DEBUG
True iff the
log level is DEBUG or less. |
protected static boolean |
INFO
True iff the
log level is INFO or less. |
protected static org.apache.log4j.Logger |
log |
DEFAULT_CHUNK_SIZE| Constructor and Description |
|---|
ChunkConsumerIterator(ICloseableIterator<E[]> src) |
ChunkConsumerIterator(ICloseableIterator<E[]> src,
IKeyOrder<E> keyOrder) |
| Modifier and Type | Method and Description |
|---|---|
void |
close()
Closes the iterator, releasing any associated resources.
|
IKeyOrder<E> |
getKeyOrder()
The natural order in which elements are being visited.
|
boolean |
hasNext() |
E |
next()
The next element available from the iterator.
|
E[] |
nextChunk()
Return the next "chunk" from the iterator.
|
E[] |
nextChunk(IKeyOrder<E> keyOrder)
Return the next "chunk" of elements.
|
void |
remove()
Removes the last element visited by
IChunkedIterator.next() (optional operation). |
protected static final org.apache.log4j.Logger log
protected static final boolean INFO
log level is INFO or less.protected static final boolean DEBUG
log level is DEBUG or less.public ChunkConsumerIterator(ICloseableIterator<E[]> src)
src - The source iterator. Note that each element visited by the
source iterator is treated as a chunk of elements by this
iterator.public ChunkConsumerIterator(ICloseableIterator<E[]> src, IKeyOrder<E> keyOrder)
src - The source iterator. Note that each element visited by the
source iterator is treated as a chunk of elements by this
iterator.keyOrder - The natural order in which the un-chunked elements in the
source iterator will be visited -or- null if no
known.public IKeyOrder<E> getKeyOrder()
IChunkedOrderedIteratorgetKeyOrder in interface IChunkedOrderedIterator<E>null if not known.public E next()
IChunkedIteratorpublic E[] nextChunk()
IChunkedIteratornextChunk in interface IChunkedIterator<E>public E[] nextChunk(IKeyOrder<E> keyOrder)
IChunkedOrderedIteratorIChunkedOrderedIterator.getKeyOrder() would return non-null
and the request order corresponds to the value that would be returned by
IChunkedOrderedIterator.getKeyOrder() then the elements in the next chunk are NOT
sorted. Otherwise the elements in the next chunk are sorted before they
are returned. The size of the chunk is up to the implementation.nextChunk in interface IChunkedOrderedIterator<E>keyOrder - The natural order for the elements in the chunk.public void remove()
IChunkedIteratorIChunkedIterator.next() (optional operation).
Note: This method is not readily suited for use with IChunkedIterator.nextChunk()
since the latter has already visited everything in the chunk and
IChunkedIterator.remove() would only remove the last item in the chunk. Normally
you will want to accumulate items to be removed in a buffer and then
submit the buffer to some batch api operation when it overflows.
Alternatively, the IRangeQuery.REMOVEALL flag may be used with
the source iterator to remove elements from the index as they are
visited.
public void close()
ICloseableIteratorICloseableIterator.close() if Iterator.hasNext()
method returns false to ensure that the iterator is closed
(and its resources release) as soon as it is exhausted.
Note: Implementations that support Iterator.remove() MUST NOT
eagerly close the iterator when it is exhausted since that would make it
impossible to remove the last visited statement. Instead they MUST wait
for an explicit ICloseableIterator.close() by the application.
close in interface ICloseableclose in interface ICloseableIterator<E>Copyright © 2006–2019 SYSTAP, LLC DBA Blazegraph. All rights reserved.