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ConcurrentHashMap.Compute(Object, IBiFunction) Method

Definition

Attempts to compute a mapping for the specified key and its current mapped value (or null if there is no current mapping).

[Android.Runtime.Register("compute", "(Ljava/lang/Object;Ljava/util/function/BiFunction;)Ljava/lang/Object;", "GetCompute_Ljava_lang_Object_Ljava_util_function_BiFunction_Handler", ApiSince=24)]
public virtual Java.Lang.Object? Compute (Java.Lang.Object key, Java.Util.Functions.IBiFunction remappingFunction);
[<Android.Runtime.Register("compute", "(Ljava/lang/Object;Ljava/util/function/BiFunction;)Ljava/lang/Object;", "GetCompute_Ljava_lang_Object_Ljava_util_function_BiFunction_Handler", ApiSince=24)>]
abstract member Compute : Java.Lang.Object * Java.Util.Functions.IBiFunction -> Java.Lang.Object
override this.Compute : Java.Lang.Object * Java.Util.Functions.IBiFunction -> Java.Lang.Object

Parameters

key
Object

key with which the specified value is to be associated

remappingFunction
IBiFunction

the function to compute a value

Returns

the new value associated with the specified key, or null if none

Implements

Attributes

Remarks

Attempts to compute a mapping for the specified key and its current mapped value (or null if there is no current mapping). The entire method invocation is performed atomically. The supplied function is invoked exactly once per invocation of this method. Some attempted update operations on this map by other threads may be blocked while computation is in progress, so the computation should be short and simple.

The remapping function must not modify this map during computation.

Java documentation for java.util.concurrent.ConcurrentHashMap.compute(K, java.util.function.BiFunction<? super K, ? super V, ? extends V>).

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.

Applies to