net.ontopia.utils
Class SoftHashMapIndex<K,E>

java.lang.Object
  net.ontopia.utils.SoftHashMapIndex<K,E>

All Implemented Interfaces:

LookupIndexIF<K,E>

Direct Known Subclasses:

TransactionalSoftHashMapIndex

public class SoftHashMapIndex<K,E>
extends java.lang.Object
implements LookupIndexIF<K,E>

INTERNAL: A lookup index implementation that uses soft references for the keys, in order to allow them to be garbage-collected. It doesn't support a fallback, since this is not needed where it is used. It's simply a cache that allows its keys to be GC-ed. Note that the keys passed in should not be SoftReferences; the index will wrap them as references where needed.

General approach is closed hashing, like in CompactHashSet. We simplify a little by assuming that null keys do not occur in put() and remove().

Nested Class Summary

static class

SoftHashMapIndex.SoftEntry<K,E>

Field Summary

SoftHashMapIndex.SoftEntry<K,E>[]

entries

Constructor Summary

SoftHashMapIndex()

Method Summary

E	get(K key)
K	getKey(K key)
E	put(K key, E value)
protected void	rehash() INTERNAL: Figures out correct size for rehashed set, then does the rehash.
E	remove(K key)
int	size()
void	writeReport(java.io.Writer out)

Methods inherited from class java.lang.Object

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

Field Detail

entries

public SoftHashMapIndex.SoftEntry<K,E>[] entries

Constructor Detail

SoftHashMapIndex

public SoftHashMapIndex()

Method Detail

get

public E get(K key)

Specified by:

get in interface LookupIndexIF<K,E>

getKey

public K getKey(K key)

put

public E put(K key,
             E value)

Specified by:

put in interface LookupIndexIF<K,E>

remove

public E remove(K key)

Specified by:

remove in interface LookupIndexIF<K,E>

rehash

protected void rehash()

INTERNAL: Figures out correct size for rehashed set, then does the rehash.

size

public int size()

writeReport

public void writeReport(java.io.Writer out)
                 throws java.io.IOException

Throws:

java.io.IOException