Package org.terrier.structures.postings

Interface IterablePosting

All Superinterfaces:

java.lang.AutoCloseable, java.io.Closeable, Posting

All Known Implementing Classes:

ANDIterablePosting, ArrayOfBasicIterablePosting, ArrayOfBlockFieldIterablePosting, ArrayOfBlockIterablePosting, ArrayOfFieldIterablePosting, ArrayOfIdsIterablePosting, BasicIterablePosting, BasicIterablePostingDocidOnly, BlockFieldIterablePosting, BlockFieldORIterablePosting, BlockIterablePosting, BlockMultiDirectIterablePosting, BlockMultiIterablePosting, BlockORIterablePosting, DocumentPostingList.postingIterator, FieldIterablePosting, FieldOnlyIterablePosting, FieldORIterablePosting, IterablePostingImpl, MemoryDirectIterablePosting, MemoryFieldsDirectIterablePosting, MemoryFieldsIterablePosting, MemoryIterablePosting, MultiDirectIterablePosting, MultiIterablePosting, ORIterablePosting, PhraseIterablePosting, ProximityIterablePosting

public interface IterablePosting
extends Posting, java.io.Closeable

An interface that allows a list of postings to be iterated over. Iteration takes place using the next() and next(int) methods, which move the iterator forwards. If the end of list is reached, END_OF_LIST is returned (alias EOL). Once EOL has been returned, getId() must also return EOL.

Since:

3.0

Author:

Craig Macdonald, Nicola Tonellotto

Field Summary

Fields

Modifier and Type	Field	Description
static int	END_OF_LIST
static int	EOL	Values which denotes that the end of the posting list has been reached.

Method Summary

Modifier and Type	Method	Description
boolean	endOfPostings()	Status method to see if this posting list iterator has been finished.
int	next()	Move this iterator to the next posting.
int	next(int targetId)	Move this iterator to the posting with specified id, or next posting after that if a posting with the specified id does not exist.

Methods inherited from interface java.io.Closeable

close

Methods inherited from interface org.terrier.structures.postings.Posting

asWritablePosting, getDocumentLength, getFrequency, getId, setId

Field Detail

EOL

static final int EOL

Values which denotes that the end of the posting list has been reached.

See Also:

Constant Field Values

END_OF_LIST

static final int END_OF_LIST

See Also:

Constant Field Values

Method Detail

next

int next()
  throws java.io.IOException

Move this iterator to the next posting.

Returns:

id of next posting, or EOL if end of posting list.

Throws:

java.io.IOException

next

int next(int targetId)
  throws java.io.IOException

Move this iterator to the posting with specified id, or next posting after that if a posting with the specified id does not exist. This is usually implemented internally by next(), but more efficient implementations can override this behaviour.

Parameters:

targetId - id of the posting to find in this posting list.

Returns:

id of the posting found, or EOL if end of posting list is reached.

Throws:

java.io.IOException

endOfPostings

boolean endOfPostings()

Status method to see if this posting list iterator has been finished.

Returns:

true if next() or next(int) would return EOL or have returned EOL.