Start the discussion by brief Overview of Java Collections vs Scala Collections
Advantages of using Scala Collections:
1. Immutable Collections provided by Scala library by default – Need google Guava library in java with verbose syntax
2. A more consistent model across i.e. Collection and Map interfaces – both are iterable unlike java where as map interface does not implement iterable interface
3. Difference between Traversable and Iterable interfaces
4. Parallel Collections
5. Scala Rich Collection API functions – like map, flatmap, foldleft, partition, zip, groupByKey etc which not only reduce the code but also very expressive.