list method in Java

* create
    * create: List\<Obj> list = new ArrayList<>(); 
    * copy: 
* add
    * prepend: 
    * append: add(Object)
    * insert: add(int index, Object)
    * extend: 
* change
    * set: set(int index, element)
    * reverse: 
    * sort: 
    * toArray: 
* query
    * compare: 
    * counts: 
    * get: get(int index)
    * head: 
    * tail: 
    * last: 
    * init: 
    * index: indexOf(element)
    * null: 
    * size: size()
* delete
    * clear: clear()
    * remove: remove(Object)
    * pop: remove(int index)