org.varienaja.util
Class DenseSet

java.lang.Object
  org.varienaja.util.DenseSet

public class DenseSet
extends java.lang.Object

A Dense Set is a set of long-values. The Set is meant to contain many consecutive longs while using as little memory as possible. The more holes there are in the list of long-values, the more memory will be consumed. The memory consumption per hole is constant and independent of the size of the hole. The advantage of a DenseSet over a BitSet, is that the DenseSet has a constant size. It can hold MAX_LONG values, and still use two longs memory. Only the holes consume memory. A Bitset containing MAX_LONG bits would take an insane amount of 2^64/8 bytes, regardless of the amount of holes. So, when the amount of holes stays low enough, the DenseSet is a better choise than a BitSet.

Author:

varienaja

Field Summary

protected java.util.Set<org.varienaja.util.Range>

_ranges

Constructor Summary

DenseSet()

Method Summary

boolean	add(long l) Adds a long to the Set of longs.
void	clear() Removes all Long-values from the Set
boolean	contains(long l) Checks whether a certain value exists in the Set.
boolean	equals(java.lang.Object o)
long	get(long index) Searches for a long-value at a specific position.
int	hashCode()
java.lang.String	prettyPrint() Returns a string representation of the contents of the set in the format: a-b,c,d-e, ...
boolean	remove(long l) /** Removes a long value from the Set of longs.
int	size()
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

_ranges

protected java.util.Set<org.varienaja.util.Range> _ranges

Constructor Detail

DenseSet

public DenseSet()

Method Detail

size

public int size()

Returns:

The amount of long-values that is contained in the Set

add

public boolean add(long l)

Adds a long to the Set of longs.

Parameters:

l - The value to be added.

Returns:

Whether the Set changed because of this operation

remove

public boolean remove(long l)

/** Removes a long value from the Set of longs.

Parameters:

l - The long-value to be removed.

Returns:

Whether the long was removed

clear

public void clear()

Removes all Long-values from the Set

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

prettyPrint

public java.lang.String prettyPrint()

Returns a string representation of the contents of the set in the format: a-b,c,d-e, ...

Returns:

A String representation of the contents of the dense set.

get

public long get(long index)

Searches for a long-value at a specific position.

Parameters:

index - The position to look in

Returns:

returns the long that is at position index in the Set

contains

public boolean contains(long l)

Checks whether a certain value exists in the Set.

Parameters:

l - The value to check for.

Returns:

True, if this value is contained in this Set, False otherwise.

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object