Sync. List or Unmodifiable List - better way.

[Laax]

Hi,

I am using a list with external sync.

What if I use the list for updation and use unmodifiable list for
iterators by different thread?

What is costly? What happens internally?
Your help is greatly appreciated.
Thanks.

 

[John C. Bollinger]

Hi,

I am using a list with external sync.

What if I use the list for updation and use unmodifiable list for
iterators by different thread?

What is costly? What happens internally?
Your help is greatly appreciated.
Thanks.

Collections.unmodifiableList(List) "returns an unmodifiable view of the
specified list." (API docs). In other words, the object returned by
that method has dynamic dependency on the original List. This means,
among other things, that an unmodifiable List does not provide any
measure of thread safety vs. concurrent modification of the original List.

Note also that if the List(s) contain mutable objects then thread safety
furthermore depends on correct synchronization of access to them.


John Bollinger
(e-mail address removed)

 

[Laax]

Hi John,

Thanks for your reply.
Your answer is a valuable one.

thanks,
Laax.