Module org.apache.lucene.core

Package org.apache.lucene.util

Class BytesRefArray

java.lang.Object

org.apache.lucene.util.BytesRefArray

All Implemented Interfaces:

SortableBytesRefArray

public final class BytesRefArray
extends Object
implements SortableBytesRefArray

A simple append only random-access BytesRef array that stores full copies of the appended bytes in a ByteBlockPool.

Note: This class is not Thread-Safe!

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	BytesRefArray.IndexedBytesRefIterator	An extension of BytesRefIterator that allows retrieving the index of the current element
static final class	BytesRefArray.SortState	Used to iterate the elements of an array in a given order.

Field Summary

Fields

Modifier and Type	Field	Description
private final Counter	bytesUsed
private int	currentOffset
private int	lastElement
private int[]	offsets
private final ByteBlockPool	pool

Constructor Summary

Constructors

Constructor	Description
BytesRefArray(Counter bytesUsed)	Creates a new BytesRefArray with a counter to track allocated bytes

Method Summary

Modifier and Type	Method	Description
int	append(BytesRef bytes)	Appends a copy of the given BytesRef to this BytesRefArray.
void	clear()	Clears this BytesRefArray
BytesRef	get(BytesRefBuilder spare, int index)	Returns the n'th element of this BytesRefArray
BytesRefIterator	iterator()	sugar for iterator(Comparator) with a null comparator
BytesRefIterator	iterator(Comparator<BytesRef> comp)	Returns a BytesRefIterator with point in time semantics.
BytesRefArray.IndexedBytesRefIterator	iterator(BytesRefArray.SortState sortState)	Returns an BytesRefArray.IndexedBytesRefIterator with point in time semantics.
private void	setBytesRef(BytesRefBuilder spare, BytesRef result, int index)	Used only by sort below, to set a BytesRef with the specified slice, avoiding copying bytes in the common case when the slice is contained in a single block in the byte block pool.
int	size()	Returns the current size of this BytesRefArray
BytesRefArray.SortState	sort(Comparator<BytesRef> comp, boolean stable)	Returns a BytesRefArray.SortState representing the order of elements in this array.

Methods inherited from class java.lang.Object

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

Field Details

pool

private final ByteBlockPool pool

offsets

private int[] offsets

lastElement

private int lastElement

currentOffset

private int currentOffset

bytesUsed

private final Counter bytesUsed

Constructor Details

BytesRefArray

public BytesRefArray(Counter bytesUsed)

Creates a new BytesRefArray with a counter to track allocated bytes

Method Details

clear

public void clear()

Clears this BytesRefArray

Specified by:

clear in interface SortableBytesRefArray

append

public int append(BytesRef bytes)

Appends a copy of the given BytesRef to this BytesRefArray.

Specified by:

append in interface SortableBytesRefArray

Parameters:

bytes - the bytes to append

Returns:

the index of the appended bytes

size

public int size()

Returns the current size of this BytesRefArray

Specified by:

size in interface SortableBytesRefArray

Returns:

the current size of this BytesRefArray

get

public BytesRef get(BytesRefBuilder spare,
 int index)

Returns the n'th element of this BytesRefArray

Parameters:

spare - a spare BytesRef instance

index - the elements index to retrieve

Returns:

the n'th element of this BytesRefArray

setBytesRef

private void setBytesRef(BytesRefBuilder spare,
 BytesRef result,
 int index)

Used only by sort below, to set a BytesRef with the specified slice, avoiding copying bytes in the common case when the slice is contained in a single block in the byte block pool.

sort

public BytesRefArray.SortState sort(Comparator<BytesRef> comp,
 boolean stable)

Returns a BytesRefArray.SortState representing the order of elements in this array. This is a non-destructive operation.

Parameters:

comp - The comparator to compare BytesRefs. A radix sort optimization is available if the comparator implements BytesRefComparator

stable - If the sort needs to be stable

Returns:

A BytesRefArray.SortState that could be used in iterator(SortState)

iterator

public BytesRefIterator iterator()

sugar for iterator(Comparator) with a null comparator

iterator

public BytesRefIterator iterator(Comparator<BytesRef> comp)

Returns a BytesRefIterator with point in time semantics. The iterator provides access to all so far appended BytesRef instances.

If a non null Comparator is provided the iterator will iterate the byte values in the order specified by the comparator. Otherwise the order is the same as the values were appended.

This is a non-destructive operation.

Specified by:

iterator in interface SortableBytesRefArray

iterator

public BytesRefArray.IndexedBytesRefIterator iterator(BytesRefArray.SortState sortState)

Returns an BytesRefArray.IndexedBytesRefIterator with point in time semantics. The iterator provides access to all so far appended BytesRef instances. If a non-null sortState is specified then the iterator will iterate the byte values in the order of the sortState; otherwise, the order is the same as the values were appended.