io.flutter.embedding.engine

Class FlutterEngineCache

java.lang.Object

io.flutter.embedding.engine.FlutterEngineCache

public class FlutterEngineCache
extends Object

Static singleton cache that holds FlutterEngine instances identified by Strings.

The ID of a given FlutterEngine can be whatever String is desired.

FlutterEngineCache is useful for storing pre-warmed FlutterEngine instances. FlutterActivity and FlutterFragment use the FlutterEngineCache singleton internally when instructed to use a cached FlutterEngine based on a given ID. See FlutterActivity.CachedEngineIntentBuilder and FlutterFragment.withCachedEngine(String) for related APIs.

Method Summary

Modifier and Type	Method and Description
void	clear() Removes all FlutterEngine's that are currently in the cache.
boolean	contains(String engineId) Returns true if a FlutterEngine in this cache is associated with the given engineId.
FlutterEngine	get(String engineId) Returns the FlutterEngine in this cache that is associated with the given engineId, or null is no such FlutterEngine exists.
static FlutterEngineCache	getInstance() Returns the static singleton instance of FlutterEngineCache.
void	put(String engineId, FlutterEngine engine) Places the given FlutterEngine in this cache and associates it with the given engineId.
void	remove(String engineId) Removes any FlutterEngine that is currently in the cache that is identified by the given engineId.

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

@NonNull
public static FlutterEngineCache getInstance()

Returns the static singleton instance of FlutterEngineCache.

Creates a new instance if one does not yet exist.

contains

public boolean contains(@NonNull
                        String engineId)

Returns true if a FlutterEngine in this cache is associated with the given engineId.

get

@Nullable
public FlutterEngine get(@NonNull
                                   String engineId)

Returns the FlutterEngine in this cache that is associated with the given engineId, or null is no such FlutterEngine exists.

put

public void put(@NonNull
                String engineId,
                @Nullable
                FlutterEngine engine)

Places the given FlutterEngine in this cache and associates it with the given engineId.

If a FlutterEngine already exists in this cache for the given engineId, that FlutterEngine is removed from this cache.

remove

public void remove(@NonNull
                   String engineId)

Removes any FlutterEngine that is currently in the cache that is identified by the given engineId.

clear

public void clear()

Removes all FlutterEngine's that are currently in the cache.