The Collection interface is a set of objects that allow duplicate. The SET interface inherits the Collection, but it is not allowed to repeat. The List interface inherits the Collection, allows you to repeat, and introduce the location subscript. The MAP interface does not inherit the set and does not inherit the Collection. The specific implementation is summarized as follows:
Interface Implementation History Set Set Hashset Treeset List ArrayList Vector LINKEDLIST Stack Map HashMap HashTable Treemap Properties Difference: ArrayList If you want to support random access, you don't have to insert or remove elements anywhere in the end of the end, ArrayList provides an optional collection; It can be seen as a dynamic array, the principle of the advanced first. LinkedList If you want to add and remove elements from the middle position of the list, as long as the order of access list elements, the LinkedList is better; can be seen as a stack, attached and advanced principle.
