Most visited

Recently visited

Results for

Summary: Ctors | Methods | Protected Methods | Inherited Methods | [Expand All]

LruCache

public class LruCache
extends Object

java.lang.Object
↳	android.support.v4.util.LruCache<K, V>

Static library version of LruCache. Used to write apps that run on API levels prior to 12. When running on API level 12 or above, this implementation is still used; it does not try to switch to the framework's implementation. See the framework SDK documentation for a class overview.

Summary

Public constructors
`LruCache(int maxSize)`

Public methods
`final int`	`createCount()` Returns the number of times `create(Object)` returned a value.
`final void`	`evictAll()` Clear the cache, calling `entryRemoved(boolean, K, V, V)` on each removed entry.
`final int`	`evictionCount()` Returns the number of values that have been evicted.
`final V`	`get(K key)` Returns the value for `key` if it exists in the cache or can be created by `#create`.
`final int`	`hitCount()` Returns the number of times `get(K)` returned a value that was already present in the cache.
`final int`	`maxSize()` For caches that do not override `sizeOf(K, V)`, this returns the maximum number of entries in the cache.
`final int`	`missCount()` Returns the number of times `get(K)` returned null or required a new value to be created.
`final V`	`put(K key, V value)` Caches `value` for `key`.
`final int`	`putCount()` Returns the number of times `put(K, V)` was called.
`final V`	`remove(K key)` Removes the entry for `key` if it exists.
`void`	`resize(int maxSize)` Sets the size of the cache.
`final int`	`size()` For caches that do not override `sizeOf(K, V)`, this returns the number of entries in the cache.
`final Map<K, V>`	`snapshot()` Returns a copy of the current contents of the cache, ordered from least recently accessed to most recently accessed.
`final String`	`toString()` Returns a string representation of the object.
`void`	`trimToSize(int maxSize)` Remove the eldest entries until the total of remaining entries is at or below the requested size.

Protected methods
`V`	`create(K key)` Called after a cache miss to compute a value for the corresponding key.
`void`	`entryRemoved(boolean evicted, K key, V oldValue, V newValue)` Called for entries that have been evicted or removed.
`int`	`sizeOf(K key, V value)` Returns the size of the entry for `key` and `value` in user-defined units.

Inherited methods

From class


  
    java.lang.Object

`Object`	`clone()` Creates and returns a copy of this object.
`boolean`	`equals(Object obj)` Indicates whether some other object is "equal to" this one.
`void`	`finalize()` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
`final Class<?>`	`getClass()` Returns the runtime class of this `Object`.
`int`	`hashCode()` Returns a hash code value for the object.
`final void`	`notify()` Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()` Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()` Returns a string representation of the object.
`final void`	`wait(long millis, int nanos)` Causes the current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed.
`final void`	`wait(long millis)` Causes the current thread to wait until either another thread invokes the `notify()` method or the `notifyAll()` method for this object, or a specified amount of time has elapsed.
`final void`	`wait()` Causes the current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object.

Public constructors

LruCache

LruCache (int maxSize)

Parameters
`maxSize`	`int`: for caches that do not override `sizeOf(K, V)`, this is the maximum number of entries in the cache. For all other caches, this is the maximum sum of the sizes of the entries in this cache.

Public methods

createCount

int createCount ()

Returns the number of times create(Object) returned a value.

Returns
`int`

evictAll

void evictAll ()

Clear the cache, calling entryRemoved(boolean, K, V, V) on each removed entry.

evictionCount

int evictionCount ()

Returns the number of values that have been evicted.

Returns
`int`

get

V get (K key)

Returns the value for key if it exists in the cache or can be created by #create. If a value was returned, it is moved to the head of the queue. This returns null if a value is not cached and cannot be created.

Parameters
`key`	`K`

Returns
`V`

hitCount

int hitCount ()

Returns the number of times get(K) returned a value that was already present in the cache.

Returns
`int`

maxSize

int maxSize ()

For caches that do not override sizeOf(K, V), this returns the maximum number of entries in the cache. For all other caches, this returns the maximum sum of the sizes of the entries in this cache.

Returns
`int`

missCount

int missCount ()

Returns the number of times get(K) returned null or required a new value to be created.

Returns
`int`

put

V put (K key, 
                V value)

Caches value for key. The value is moved to the head of the queue.

Parameters
`key`	`K`
`value`	`V`

Returns
`V`	the previous value mapped by `key`.

putCount

int putCount ()

Returns the number of times put(K, V) was called.

Returns
`int`

remove

V remove (K key)

Removes the entry for key if it exists.

Parameters
`key`	`K`

Returns
`V`	the previous value mapped by `key`.

resize

void resize (int maxSize)

Sets the size of the cache.

Parameters
`maxSize`	`int`: The new maximum size.

size

int size ()

For caches that do not override sizeOf(K, V), this returns the number of entries in the cache. For all other caches, this returns the sum of the sizes of the entries in this cache.

Returns
`int`

snapshot

Map<K, V> snapshot ()

Returns a copy of the current contents of the cache, ordered from least recently accessed to most recently accessed.

Returns
`Map<K, V>`

toString

String toString ()

Returns a string representation of the object. In general, the toString method returns a string that "textually represents" this object. The result should be a concise but informative representation that is easy for a person to read. It is recommended that all subclasses override this method.

The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', and the unsigned hexadecimal representation of the hash code of the object. In other words, this method returns a string equal to the value of:

 getClass().getName() + '@' + Integer.toHexString(hashCode())

Returns
`String`	a string representation of the object.

trimToSize

void trimToSize (int maxSize)

Remove the eldest entries until the total of remaining entries is at or below the requested size.

Parameters
`maxSize`	`int`: the maximum size of the cache before returning. May be -1 to evict even 0-sized elements.

Protected methods

create

V create (K key)

Called after a cache miss to compute a value for the corresponding key. Returns the computed value or null if no value can be computed. The default implementation returns null.

The method is called without synchronization: other threads may access the cache while this method is executing.

If a value for key exists in the cache when this method returns, the created value will be released with entryRemoved(boolean, K, V, V) and discarded. This can occur when multiple threads request the same key at the same time (causing multiple values to be created), or when one thread calls put(K, V) while another is creating a value for the same key.

Parameters
`key`	`K`

Returns
`V`

entryRemoved

void entryRemoved (boolean evicted, 
                K key, 
                V oldValue, 
                V newValue)

Called for entries that have been evicted or removed. This method is invoked when a value is evicted to make space, removed by a call to remove(K), or replaced by a call to put(K, V). The default implementation does nothing.

The method is called without synchronization: other threads may access the cache while this method is executing.

Parameters
`evicted`	`boolean`: true if the entry is being removed to make space, false if the removal was caused by a `put(K, V)` or `remove(K)`.
`key`	`K`
`oldValue`	`V`
`newValue`	`V`: the new value for `key`, if it exists. If non-null, this removal was caused by a `put(K, V)`. Otherwise it was caused by an eviction or a `remove(K)`.

sizeOf

int sizeOf (K key, 
                V value)

Returns the size of the entry for key and value in user-defined units. The default implementation returns 1 so that size is the number of entries and max size is the maximum number of entries.

An entry's size must not change while it is in the cache.

Parameters
`key`	`K`
`value`	`V`

Returns
`int`

Interfaces

Classes

Most visited

Recently visited

Results for

LruCache

Summary

Public constructors

Public methods

Protected methods

Inherited methods

Public constructors

LruCache

Public methods

createCount

evictAll

evictionCount

get

hitCount

maxSize

missCount

put

putCount

remove

resize

size

snapshot

toString

trimToSize

Protected methods

create

entryRemoved

sizeOf