SparseIntArray

public class SparseIntArray
extends Object

java.lang.Object
   ↳ com.android.utils.SparseIntArray

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

Summary

Public constructors

SparseIntArray()

Creates a new SparseIntArray containing no mappings.

SparseIntArray(int initialCapacity)

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

Public methods

void append(int key, int 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 SparseIntArray.

void delete(int key)

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

int get(int key)

Gets the int mapped from the specified key, or 0 if no such mapping has been made.

int get(int key, int valueIfKeyNotFound)

Gets the int 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(int 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 index th key-value mapping that this SparseIntArray stores.

void put(int key, int value)

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

void removeAt(int index)

Removes the mapping at the given index.

int size()

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

int valueAt(int index)

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

Public constructors

SparseIntArray

public SparseIntArray ()

Creates a new SparseIntArray containing no mappings.

SparseIntArray

public SparseIntArray (int initialCapacity)

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

Parameters
initialCapacity int

Public methods

append

public void append (int key, 
                int 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.

Parameters
key int

value int

clear

public void clear ()

Removes all key-value mappings from this SparseIntArray.

delete

public void delete (int key)

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

Parameters
key int

get

public int get (int key)

Gets the int mapped from the specified key, or 0 if no such mapping has been made.

Parameters
key int

Returns
int

get

public int get (int key, 
                int valueIfKeyNotFound)

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

Parameters
key int

valueIfKeyNotFound int

Returns
int

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.

Parameters
key int

Returns
int

indexOfValue

public int indexOfValue (int 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.

Parameters
value int

Returns
int

keyAt

public int keyAt (int index)

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

Parameters
index int

Returns
int

put

public void put (int key, 
                int value)

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

Parameters
key int

value int

removeAt

public void removeAt (int index)

Removes the mapping at the given index.

Parameters
index int

size

public int size ()

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

Returns
int

valueAt

public int valueAt (int index)

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

Parameters
index int

Returns
int