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

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	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.