android.util
Class SparseBooleanArray

java.lang.Object
  android.util.SparseBooleanArray

public class SparseBooleanArray
extends Object

SparseBooleanArrays map integers to booleans. Unlike a normal array of booleans there can be gaps in the indices. It is intended to be more efficient than using a HashMap to map Integers to Booleans.

Constructor Summary

SparseBooleanArray()
Creates a new SparseBooleanArray containing no mappings.

SparseBooleanArray(int initialCapacity)
Creates a new SparseBooleanArray containing no mappings that will not require any additional memory allocation to store the specified number of mappings.

Method Summary

void	append(int key, boolean value) Puts a key/value pair into the array, optimizing for the case where the key is greater than all existing keys in the array.
void	clear() Removes all key-value mappings from this SparseBooleanArray.
void	delete(int key) Removes the mapping from the specified key, if there was any.
boolean	get(int key) Gets the boolean mapped from the specified key, or false if no such mapping has been made.
boolean	get(int key, boolean valueIfKeyNotFound) Gets the boolean mapped from the specified key, or the specified value if no such mapping has been made.
int	indexOfKey(int key) Returns the index for which keyAt(int) would return the specified key, or a negative number if the specified key is not mapped.
int	indexOfValue(boolean value) Returns an index for which valueAt(int) would return the specified key, or a negative number if no keys map to the specified value.
int	keyAt(int index) Given an index in the range 0...size()-1, returns the key from the indexth key-value mapping that this SparseBooleanArray stores.
void	put(int key, boolean value) Adds a mapping from the specified key to the specified value, replacing the previous mapping from the specified key if there was one.
int	size() Returns the number of key-value mappings that this SparseBooleanArray currently stores.
boolean	valueAt(int index) Given an index in the range 0...size()-1, returns the value from the indexth key-value mapping that this SparseBooleanArray stores.

Methods inherited from class java.lang.Object

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

Constructor Detail

SparseBooleanArray

public SparseBooleanArray()

Creates a new SparseBooleanArray containing no mappings.

SparseBooleanArray

public SparseBooleanArray(int initialCapacity)

Creates a new SparseBooleanArray containing no mappings that will not require any additional memory allocation to store the specified number of mappings.

Method Detail

get

public boolean get(int key)

Gets the boolean mapped from the specified key, or false if no such mapping has been made.

get

public boolean get(int key,
                   boolean valueIfKeyNotFound)

Gets the boolean mapped from the specified key, or the specified value if no such mapping has been made.

delete

public void delete(int key)

Removes the mapping from the specified key, if there was any.

put

public void put(int key,
                boolean value)

Adds a mapping from the specified key to the specified value, replacing the previous mapping from the specified key if there was one.

size

public int size()

Returns the number of key-value mappings that this SparseBooleanArray currently stores.

keyAt

public int keyAt(int index)

Given an index in the range 0...size()-1, returns the key from the indexth key-value mapping that this SparseBooleanArray stores.

valueAt

public boolean valueAt(int index)

Given an index in the range 0...size()-1, returns the value from the indexth key-value mapping that this SparseBooleanArray stores.

indexOfKey

public int indexOfKey(int key)

Returns the index for which keyAt(int) would return the specified key, or a negative number if the specified key is not mapped.

indexOfValue

public int indexOfValue(boolean value)

Returns an index for which valueAt(int) would return the specified key, or a negative number if no keys map to the specified value. Beware that this is a linear search, unlike lookups by key, and that multiple keys can map to the same value and this will find only one of them.

clear

public void clear()

Removes all key-value mappings from this SparseBooleanArray.

append

public void append(int key,
                   boolean value)

Puts a key/value pair into the array, optimizing for the case where the key is greater than all existing keys in the array.