Scala - Mutable thread safe collections

Question

I need a mutable thread safe Map and a mutable thread safe List in Scala. I know that the immutable collections are thread safe by default. But, I need to update my collecti

Answer 1

Fast hint for those coming to this in 2018 or later:

import java.util.concurrent.ConcurrentHashMap

val m: ConcurrentHashMap[String,MyClass] = new ConcurrentHashMap

Answer 2

1. You're duplicating topics....

2. As was mentioned by AlexIv in his answer, there's a trait you can mix in if you want thread safety. There's another way though:

   val synchronizedMap = new scala.collection.mutable.LinkedHashMap[String, Any]() with scala.collection.mutable.SynchronizedMap[String, Any]
   

That should give you the map with synchronization on each access. Easy, but might not meet the performance requirements. If so, it would be probably easier to create a custom class extending the LinkedHashMap, mixing in the concurrent.Map trait (as was suggested) and provide the implementation of relevant methods, i.e: putIfAbsent, remove replace (2 overloads).