Consider a text file of names, with one name per line, that has been compiled from several different sources. A sample is shown below:

Question

Brooke Trout
Dinah Soars
Jed Dye
Brooke Trout
Jed Dye
Paige Turner

There are duplicate names in the file. We would like to generate an invitation list but don’t want to send multiple invitations to the same person. Write a program that eliminates the duplicate names by using a HashSet. Read each name from the file, add it to the HashSet, and then output all names in the HashSet to generate the invitation list without duplicates.

The solution is a fairly straightforward implementation of a HashSet that holds each name and we loop through the file checking to see if a name is in the set before adding it. It may be worth mentioning that equals and hashcode must be overwritten if the student wants to use HashSet with their own set.

Answer 1

See the code in InviteList.java and data in names.txt