Can anyone say how many null values are allowed in the following collections: (1) ArrayList (2) TreeMap (3) LinkedList (4) HashSet (5) HashMap I know hashtable does not allow any null values. The API does not clearly say this. It just says ArrayList, etc. allow values including null. TIA.
(1) ArrayList (2) TreeMap (3) LinkedList (4) HashSet (5) HashMap All of them allow null values. Try it. The only thing is in a set values must be unique. SO if you add another null the value will not be added or it will be removed and a new null value be added i don't remember.