de.lmu.ifi.dbs.elki.database
Class DistanceCache<D extends Distance<D>>

java.lang.Object
  de.lmu.ifi.dbs.elki.database.DistanceCache<D>

public class DistanceCache<D extends Distance<D>>
extends Object

Provides a cache for distances between database objects.

Author:

Elke Achtert

Field Summary

private Map<Integer,Map<Integer,D>>

cache The map holding the pairwise distances.

Constructor Summary

DistanceCache()

Method Summary

boolean	containsKey(Integer id1, Integer id2) Returns true if this cache contains a distance value for the specified ids.
D	get(Integer id1, Integer id2) Returns the distance value of the specified ids if it has been cached, null otherwise.
void	put(Integer id1, Integer id2, D distance) Puts the specified distance value for the given ids to cache.

Methods inherited from class java.lang.Object

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

Field Detail

cache

private Map<Integer,Map<Integer,D extends Distance<D>>> cache

The map holding the pairwise distances.

Constructor Detail

DistanceCache

public DistanceCache()

Method Detail

put

public void put(Integer id1,
                Integer id2,
                D distance)

Puts the specified distance value for the given ids to cache.

Parameters:

id1 - the first id

id2 - the second id

distance - the distance value

get

public D get(Integer id1,
             Integer id2)

Returns the distance value of the specified ids if it has been cached, null otherwise.

Parameters:

id1 - the first id

id2 - the second id

Returns:

the distance value of the specified ids if it has been cached, null otherwise

containsKey

public boolean containsKey(Integer id1,
                           Integer id2)

Returns true if this cache contains a distance value for the specified ids.

Parameters:

id1 - the first id

id2 - the second id

Returns:

true if this cache contains a distance value for the specified ids, false otherwise