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LongSparseArray Class

Definition

SparseArray mapping longs to Objects.

[Android.Runtime.Register("android/util/LongSparseArray", DoNotGenerateAcw=true)]
[Java.Interop.JavaTypeParameters(new System.String[] { "E" })]
public class LongSparseArray : Java.Lang.Object, IDisposable, Java.Interop.IJavaPeerable, Java.Lang.ICloneable
[<Android.Runtime.Register("android/util/LongSparseArray", DoNotGenerateAcw=true)>]
[<Java.Interop.JavaTypeParameters(new System.String[] { "E" })>]
type LongSparseArray = class
    inherit Object
    interface ICloneable
    interface IJavaObject
    interface IDisposable
    interface IJavaPeerable
Inheritance
LongSparseArray
Attributes
Implements

Remarks

SparseArray mapping longs to Objects. Unlike a normal array of Objects, there can be gaps in the indices. It is intended to be more memory efficient than using a HashMap to map Longs to Objects, both because it avoids auto-boxing keys and its data structure doesn't rely on an extra entry object for each mapping.

Note that this container keeps its mappings in an array data structure, using a binary search to find keys. The implementation is not intended to be appropriate for data structures that may contain large numbers of items. It is generally slower than a traditional HashMap, since lookups require a binary search and adds and removes require inserting and deleting entries in the array. For containers holding up to hundreds of items, the performance difference is not significant, less than 50%.

To help with performance, the container includes an optimization when removing keys: instead of compacting its array immediately, it leaves the removed entry marked as deleted. The entry can then be re-used for the same key, or compacted later in a single garbage collection step of all removed entries. This garbage collection will need to be performed at any time the array needs to be grown or the the map size or entry values are retrieved.

It is possible to iterate over the items in this container using #keyAt(int) and #valueAt(int). Iterating over the keys using keyAt(int) with ascending values of the index will return the keys in ascending order, or the values corresponding to the keys in ascending order in the case of valueAt(int).

Java documentation for android.util.LongSparseArray.

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Constructors

LongSparseArray()

Creates a new LongSparseArray containing no mappings.

LongSparseArray(Int32)

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

LongSparseArray(IntPtr, JniHandleOwnership)

A constructor used when creating managed representations of JNI objects; called by the runtime.

Properties

Class

Returns the runtime class of this Object.

(Inherited from Object)
Handle

The handle to the underlying Android instance.

(Inherited from Object)
JniIdentityHashCode (Inherited from Object)
JniPeerMembers
PeerReference (Inherited from Object)
ThresholdClass

This API supports the Mono for Android infrastructure and is not intended to be used directly from your code.

ThresholdType

This API supports the Mono for Android infrastructure and is not intended to be used directly from your code.

Methods

Append(Int64, Object)

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

Clear()

Removes all key-value mappings from this LongSparseArray.

Clone()

Creates and returns a copy of this Object.

Delete(Int64)

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

Dispose() (Inherited from Object)
Dispose(Boolean) (Inherited from Object)
Equals(Object)

Indicates whether some other object is "equal to" this one.

(Inherited from Object)
Get(Int64, Object)

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

Get(Int64)

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

GetHashCode()

Returns a hash code value for the object.

(Inherited from Object)
IndexOfKey(Int64)

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

IndexOfValue(Object)

Returns an index for which #valueAt would return the specified key, or a negative number if no keys map to the specified value.

JavaFinalize()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.

(Inherited from Object)
KeyAt(Int32)

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

Notify()

Wakes up a single thread that is waiting on this object's monitor.

(Inherited from Object)
NotifyAll()

Wakes up all threads that are waiting on this object's monitor.

(Inherited from Object)
Put(Int64, Object)

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

Remove(Int64)

Alias for #delete(long).

RemoveAt(Int32)

Removes the mapping at the specified index.

SetHandle(IntPtr, JniHandleOwnership)

Sets the Handle property.

(Inherited from Object)
SetValueAt(Int32, Object)

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

Size()

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

ToArray<T>() (Inherited from Object)
ToString()

Returns a string representation of the object.

(Inherited from Object)
UnregisterFromRuntime() (Inherited from Object)
ValueAt(Int32)

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

Wait()

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>.

(Inherited from Object)
Wait(Int64, Int32)

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed.

(Inherited from Object)
Wait(Int64)

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed.

(Inherited from Object)

Explicit Interface Implementations

IJavaPeerable.Disposed() (Inherited from Object)
IJavaPeerable.DisposeUnlessReferenced() (Inherited from Object)
IJavaPeerable.Finalized() (Inherited from Object)
IJavaPeerable.JniManagedPeerState (Inherited from Object)
IJavaPeerable.SetJniIdentityHashCode(Int32) (Inherited from Object)
IJavaPeerable.SetJniManagedPeerState(JniManagedPeerStates) (Inherited from Object)
IJavaPeerable.SetPeerReference(JniObjectReference) (Inherited from Object)

Extension Methods

JavaCast<TResult>(IJavaObject)

Performs an Android runtime-checked type conversion.

JavaCast<TResult>(IJavaObject)
GetJniTypeName(IJavaPeerable)

Applies to