DROP UI file upload , accept text and excel file and process it

DROP UI file upload , accept text and excel file and process it

I want a functionality of dropping only .txt or .xls file into my web page e.g. within div tags. Once file is dropped it should send the contents to Java (using call back method or so) or parse the file by itself and send data for further processing.

Please let me know is it possible?If possible how to?