Write a Junit test case for minimum character only

public void menu(Get get) throws IOException, FileNotFoundException { Character min = 'a'; Character max = 'f'; Inputs input = new Input(); while(true) { System.out.println("a. Import contacts from file"); System.out.println("b. Add contact"); System.out.println("c. Delete contact"); System.out.println("d. Search contact"); System.out.println("e. List contact list"); System.out.println("f. Exit program"); Character info = scan.next().toLowerCase().charAt(0); switch (info) { case 'a': System.out.println("Enter directory: "); System.out.println("no extension"); String contact = scan.next() + ".txt"; File file = new File(contact); get.readFromFile(file); break; case 'b': get.add(input); break; case 'c': System.out.println("Enter last name"); String remove = scan.next(); get.remove(remove + ".*"); break; case 'd': System.out.println("Search by last name:"); String last = scan.next(); ab.find(last + ".*"); break; case 'e': get.list(); break; case 'f': System.out.println("Stopping the program"); System.exit(0); default: System.out.println("A - F only"); break; } } }