Package com.arcadedb.index

Class CompressedRID2RIDsIndex

java.lang.Object

com.arcadedb.index.CompressedRID2RIDsIndex

public class CompressedRID2RIDsIndex
extends Object

Map like optimized to avoid stressing the GC by using mechanical sympathy technique + compression of key and values. This class is not synchronized. The key is a RID and values are pairs of RIDs. This Map implementation doesn't support the overwrite of a value. Values cannot be null.
This index is used for invert incoming edge creation.
A Binary object is used to store the hash table (the first part of it) and then keys and values. The RID key is serialized compressed in the position pointed by the hash table, then a fixed-size integer containing the next entry (with the same hash) and after that the compressed RIDs pair (edge+vertex). Another slot is kept to point to the previous entry. The hash table always points to the last element with a linked list in the only direction of the previous.

TODO support up to 4GB by using unsigned int

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	CompressedRID2RIDsIndex.EntryIterator

Field Summary

Fields

Modifier and Type	Field	Description
protected Binary	chunk
protected Database	database
protected int	keys
protected BinarySerializer	serializer
protected int	totalEntries
protected int	totalUsedSlots

Constructor Summary

Constructors

Constructor	Description
CompressedRID2RIDsIndex(Database database, int expectedVertices, int expectedEdges)
CompressedRID2RIDsIndex(Database database, Binary buffer)

Method Summary

Modifier and Type	Method	Description
boolean	containsKey(RID key)
CompressedRID2RIDsIndex.EntryIterator	entryIterator()
List<Pair<RID,RID>>	get(RID key)
int	getChunkAllocated()
int	getChunkSize()
int	getKeys()
int	getTotalUsedSlots()
boolean	isEmpty()
void	put(RID key, RID edgeRID, RID vertexRID)
void	setReadOnly()
int	size()

Methods inherited from class java.lang.Object

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

Field Detail

database

protected final Database database

serializer

protected final BinarySerializer serializer

keys

protected final int keys

chunk

protected Binary chunk

totalEntries

protected int totalEntries

totalUsedSlots

protected int totalUsedSlots

Constructor Detail

CompressedRID2RIDsIndex

public CompressedRID2RIDsIndex(Database database,
                               int expectedVertices,
                               int expectedEdges)

CompressedRID2RIDsIndex

public CompressedRID2RIDsIndex(Database database,
                               Binary buffer)

Method Detail

size

public int size()

setReadOnly

public void setReadOnly()

isEmpty

public boolean isEmpty()

containsKey

public boolean containsKey(RID key)

get

public List<Pair<RID,RID>> get(RID key)

put

public void put(RID key,
                RID edgeRID,
                RID vertexRID)

getKeys

public int getKeys()

entryIterator

public CompressedRID2RIDsIndex.EntryIterator entryIterator()

getChunkSize

public int getChunkSize()

getChunkAllocated

public int getChunkAllocated()

getTotalUsedSlots

public int getTotalUsedSlots()