Set, List,arraylist,linkedlist,vectory,hashmap,hashtable,hashset,treeset,treeset

Set and List differences:

Both are interfaces, and inherit the collection interface; List order, allow repetition, set unordered, cannot repeat;

the difference between ArrayList and linklist:

ArrayList is a dynamic array, the query efficiency is high, while Linklist is a doubly linked list, the insertion and deletion efficiency is high;

　　

The difference between HashMap and Hashtable:

　　　　Implement the Map interface; HashMap is thread asynchronous (ArrayList is also), Hashtable is synchronous (Vectory also), you can use the Collections.synchronizedmap method to achieve synchronization; HashMap allows null key value pairs;

Set, List,arraylist,linkedlist,vectory,hashmap,hashtable,hashset,treeset,treeset