Separate collection framework
Collection: single root interface collection class, for storing a series of elements meet certain rules. Set List and its sub-interfaces
List: is the ordered set, store and retrieve the same element order. It allows storing duplicate elements. An index, you can use ordinary for loop
Set: Storage is not repeating elements. There is no index (can not use ordinary for loop iterates).
Detailed List:
Since List is indexed, it is possible, according to the index increase at a particular location, returned, removed, replaced, data
public void add(int index,E element)
public E get(int index)
public E remove(int index)
public E set(int index,E element)
ArrayList
The underlying array structures, additions and deletions slow, fast look. Each add an element, all you need to create a new ArrayList, copy the old data plus new elements.
LinkedList
The bottom of the list structure, look slow, fast additions and deletions. Head and tail of the list is a good query, so there are a lot of additions and deletions head element and the tail element change search.
Vector
Single-threaded array
Set Detailed
HashSet
Miscellaneous storage element, and the element will not be repeated.
When adding elements rely HashCode () method to calculate a hash value,
Without the hash value is stored, returns to true.
If the hash value, through equals () method for determining values of two elements, if two elements are equal, the hash will produce a conflict, it returns false. If not equal, put the storage element to the collection, return true.
LinkedHashSet
+ Underlying hash table linked list order of the elements can be recorded, it is possible to ensure an orderly elements.
