Package it.unimi.di.big.mg4j.index

Class BitStreamHPIndexReader

java.lang.Object

it.unimi.di.big.mg4j.index.AbstractIndexReader

it.unimi.di.big.mg4j.index.BitStreamHPIndexReader

All Implemented Interfaces:

IndexReader, SafelyCloseable, Closeable, AutoCloseable

public class BitStreamHPIndexReader
extends AbstractIndexReader

A bitstream-based index reader for high-performance indices.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	BitStreamHPIndexReader.BitStreamHPIndexReaderIndexIterator

Field Summary

Fields

Modifier and Type	Field	Description
protected BitStreamHPIndex	index	The reference index.
protected BitStreamHPIndexReader.BitStreamHPIndexReaderIndexIterator	indexIterator	The IndexIterator view of this reader (returned by documents(CharSequence)).

Fields inherited from class it.unimi.di.big.mg4j.index.AbstractIndexReader

closed

Constructor Summary

Constructors

Constructor	Description
BitStreamHPIndexReader(BitStreamHPIndex index, InputBitStream ibs, InputBitStream positions)	Creates a new skip index reader, with the specified underlying Index and input bit stream.

Method Summary

Modifier and Type	Method	Description
void	close()
IndexIterator	documents(long term)	Returns a document iterator over the documents containing a term.
IndexIterator	documents(CharSequence term)	Returns an index iterator over the documents containing a term; the term is given explicitly.
IndexIterator	nextIterator()	Throws an UnsupportedOperationException.
String	toString()

Methods inherited from class it.unimi.di.big.mg4j.index.AbstractIndexReader

finalize

Methods inherited from class java.lang.Object

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

Field Detail

index

protected final BitStreamHPIndex index

The reference index.

indexIterator

protected final BitStreamHPIndexReader.BitStreamHPIndexReaderIndexIterator indexIterator

The IndexIterator view of this reader (returned by documents(CharSequence)).

Constructor Detail

BitStreamHPIndexReader

public BitStreamHPIndexReader(BitStreamHPIndex index,
                              InputBitStream ibs,
                              InputBitStream positions)

Creates a new skip index reader, with the specified underlying Index and input bit stream.

Parameters:

index - the index.

ibs - the underlying bit stream.

Method Detail

documents

public IndexIterator documents(long term)
                        throws IOException

Description copied from interface: IndexReader

Returns a document iterator over the documents containing a term.

Note that the index iterator returned by this method will return null on a call to term().

Note that it is always possible to call this method with argument 0, even if the underlying index does not provide random access.

Parameters:

term - the number of a term.

Throws:

IOException

documents

public IndexIterator documents(CharSequence term)
                        throws IOException

Description copied from interface: IndexReader

Returns an index iterator over the documents containing a term; the term is given explicitly.

Unless the term processor of the associated index is null, words coming from a query will have to be processed before being used with this method.

Note that the index iterator returned by this method will return term on a call to term().

Parameters:

term - a term (the term will be downcased if the index is case insensitive).

Throws:

IOException

nextIterator

public IndexIterator nextIterator()
                           throws IOException

Description copied from class: AbstractIndexReader

Throws an UnsupportedOperationException.

Specified by:

nextIterator in interface IndexReader

Overrides:

nextIterator in class AbstractIndexReader

Returns:

the index iterator of the next term, or null if there are no more terms after the current one.

Throws:

IOException

toString

public String toString()

Overrides:

toString in class Object

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class AbstractIndexReader

Throws:

IOException