IConcurrentMap.PutIfAbsent(Object, Object) Method
Definition
Important
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If the specified key is not already associated with a value, associates it with the given value.
[Android.Runtime.Register("putIfAbsent", "(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;", "GetPutIfAbsent_Ljava_lang_Object_Ljava_lang_Object_Handler:Java.Util.Concurrent.IConcurrentMapInvoker, Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null")]
public Java.Lang.Object? PutIfAbsent (Java.Lang.Object? key, Java.Lang.Object? value);
[<Android.Runtime.Register("putIfAbsent", "(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;", "GetPutIfAbsent_Ljava_lang_Object_Ljava_lang_Object_Handler:Java.Util.Concurrent.IConcurrentMapInvoker, Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null")>]
abstract member PutIfAbsent : Java.Lang.Object * Java.Lang.Object -> Java.Lang.Object
Parameters
- key
- Object
key with which the specified value is to be associated
- value
- Object
value to be associated with the specified key
Returns
the previous value associated with the specified key, or
null
if there was no mapping for the key.
(A null
return can also indicate that the map
previously associated null
with the key,
if the implementation supports null values.)
Implements
- Attributes
Remarks
If the specified key is not already associated with a value, associates it with the given value. This is equivalent to, for this map
:
{@code
if (!map.containsKey(key))
return map.put(key, value);
else
return map.get(key);}
except that the action is performed atomically.
Java documentation for java.util.concurrent.ConcurrentMap.putIfAbsent(K, 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.