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Android APIs
public class

LongSparseArray

extends Object
implements Cloneable
java.lang.Object
   ↳ android.support.v4.util.LongSparseArray<E>

Class Overview

SparseArray mapping longs to Objects. Unlike a normal array of Objects, there can be gaps in the indices. It is intended to be more efficient than using a HashMap to map Longs to Objects.

Summary

Public Constructors

? Examples
LongSparseArray()
Creates a new LongSparseArray containing no mappings.

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

? Examples
void append(long key, E 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.

? Examples
void clear()
Removes all key-value mappings from this LongSparseArray.

? Examples
LongSparseArray<E> clone()
Creates and returns a copy of this Object.

? Examples
void delete(long key)
Removes the mapping from the specified key, if there was any.

? Examples
E get(long key, E valueIfKeyNotFound)
Gets the Object mapped from the specified key, or the specified Object if no such mapping has been made.

? Examples
E get(long key)
Gets the Object mapped from the specified key, or null if no such mapping has been made.

? Examples
static int idealByteArraySize(int need)

? Examples
static int idealLongArraySize(int need)

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

? Examples
int indexOfValue(E 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.

? Examples
long keyAt(int index)
Given an index in the range 0...size()-1, returns the key from the indexth key-value mapping that this LongSparseArray stores.

? Examples
void put(long key, E value)
Adds a mapping from the specified key to the specified value, replacing the previous mapping from the specified key if there was one.

? Examples
void remove(long key)
Alias for delete(long).

? Examples
void removeAt(int index)
Removes the mapping at the specified index.

? Examples
void setValueAt(int index, E value)
Given an index in the range 0...size()-1, sets a new value for the indexth key-value mapping that this LongSparseArray stores.

? Examples
int size()
Returns the number of key-value mappings that this LongSparseArray currently stores.

? Examples
E valueAt(int index)
Given an index in the range 0...size()-1, returns the value from the indexth key-value mapping that this LongSparseArray stores.
[Expand]
Inherited Methods
From class java.lang.Object

Public Constructors

public LongSparseArray ()

Creates a new LongSparseArray containing no mappings.

public LongSparseArray (int initialCapacity)

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

Public Methods

public void append (long key, E 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.

public void clear ()

Removes all key-value mappings from this LongSparseArray.

public LongSparseArray<E> clone ()

Creates and returns a copy of this Object. The default implementation returns a so-called "shallow" copy: It creates a new instance of the same class and then copies the field values (including object references) from this instance to the new instance. A "deep" copy, in contrast, would also recursively clone nested objects. A subclass that needs to implement this kind of cloning should call super.clone() to create the new instance and then create deep copies of the nested, mutable objects.

Returns
  • a copy of this object.

public void delete (long key)

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

public E get (long key, E valueIfKeyNotFound)

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

public E get (long key)

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

public static int idealByteArraySize (int need)

public static int idealLongArraySize (int need)

public int indexOfKey (long key)

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

public int indexOfValue (E 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.

public long keyAt (int index)

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

public void put (long key, E value)

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

public void remove (long key)

Alias for delete(long).

public void removeAt (int index)

Removes the mapping at the specified index.

public void setValueAt (int index, E value)

Given an index in the range 0...size()-1, sets a new value for the indexth key-value mapping that this LongSparseArray stores.

public int size ()

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

public E valueAt (int index)

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

No examples for this method.
Frequently called with: [Clear]
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