Double underscore (__), differnetiates differnet parts of the file name. Part1 --> value before first __ (example, address_change) Part2 --> value after first __ and before second__ (example, customer_request, corres_in) Part3 --> value after second __ (example, 111, 222)
I am able to read the file names and get the values for Part1, Part2 and Part3. The file names with similar Part3 need to be handled in the same way. Example, files 1 and 2, need to be handled differently from files 3,4 and 5.
So to distinguish files based on Part3, I want to create a datastructure such as Map<String, <List<String>>
example, The Map which has first key as 111 and value is an Arraylist containing address_change__customer_request__111.pdf and address_change__corres_in__111.pdf Second key in the Map is 222 and value is an ArrayList containing values address_change__signature_card__222.pdf, address_change__customer_request__222.pdf and address_change__corres_in__222.pdf
You mean you want to use one part of the String as a key to get a List<String> as the value and add the remainder of the String to the List? You just need to make sure to put a new List<String> into the Map if it doesn't contain that particular key.
That's what you have to do. Go through the Map interface API documentation and all the functionality you need is there.