org.h2.util
Class HashBase

java.lang.Object
  org.h2.util.HashBase

Direct Known Subclasses:

IntIntHashMap, ValueHashMap

public abstract class HashBase
extends java.lang.Object

The base for other hash classes.

Field Summary

protected int	deletedCount The number of deleted slots.
protected int	len The number of slots in the table.
protected int	level The level.
protected int	mask The bit mask to get the index from the hash code.
protected int	size The number of occupied slots, excluding the zero key (if any).
protected boolean	zeroKey Whether the zero key is used.

Constructor Summary

HashBase()

Method Summary

protected void	checkSizeRemove() Check the size before removing an entry.
protected int	getIndex(int hash) Calculate the index for this hash code.
protected abstract void	rehash(int newLevel) Increase the size of the underlying table and re-distribute the elements.
protected void	reset(int newLevel) Clear the map and reset the level to the specified value.
int	size() Get the size of the map.

Methods inherited from class java.lang.Object

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

Field Detail

mask

protected int mask

The bit mask to get the index from the hash code.

len

protected int len

The number of slots in the table.

size

protected int size

The number of occupied slots, excluding the zero key (if any).

deletedCount

protected int deletedCount

The number of deleted slots.

level

protected int level

The level. The number of slots is 2 ^ level.

zeroKey

protected boolean zeroKey

Whether the zero key is used.

Constructor Detail

HashBase

public HashBase()

Method Detail

rehash

protected abstract void rehash(int newLevel)

Increase the size of the underlying table and re-distribute the elements.

Parameters:

newLevel - the new level

size

public int size()

Get the size of the map.

Returns:

the size

checkSizeRemove

protected void checkSizeRemove()

Check the size before removing an entry. This method resizes the map if required.

reset

protected void reset(int newLevel)

Clear the map and reset the level to the specified value.

Parameters:

newLevel - the new level

getIndex

protected int getIndex(int hash)

Calculate the index for this hash code.

Parameters:

hash - the hash code

Returns:

the index