List interface is also an implementation of Collections interface which is needed if we want duplicate entries. In other words List will allow duplicate elements to be added in it.
The concrete implementations of List are:
It is used to add an element at the end of the 'List' .
It is used to insert an element into the 'List' at a particular position mentioned in the index.
i.e. If you want to add an element/Object at the 3rd position of the existing List. This method helps you to achieve that.
It is used to add all elements of 'Collection' into the 'List' at a particular position mentioned in the index.
It is used to return an object stored at a particular location mentioned in the index.
i.e. Say if you want to store in Object/element at the 3rd position of the List. This method comes handy in that case.
It is used to replace an element at a particular location mentioned in the index.
It is used to delete an element at a particular location mentioned in the index and return the deleted element.
It is used to Iterate the elements in the List. Say, you have 10 elements in a List and want to iterate them one by one. listIterator() helps you to achieve that.
It is also used to Iterate the elements in the List but from a specific position mentioned in the 'index'.
i.e.Say, you have 10 elements in a List and want to iterate them starting from the 5th one. You can achieve that using this method.