which Collection Class is synchronied?

[guo mark]

Ara all Collection Class unsynchronied? or there are some synchronied and some unsynchronied?

[Corey McGlone]

Some are and some aren't. For example, ArrayList isn't synchronized while Vector is. Your best resource would be to check the API for whichever classes you're interested in.
Corey

[guo mark]

3x

[Rob Ross]

Well, specifically Vector and HashTable are synchronized. All the other collection classes are unsynchronized. However, you can obtain a synchronized wrapper for the collection classes via the Collections class; but the default implementations are all unsynchronized (except for Vector and HashTable)