In this program you will replace the linked list from Program 1 with a
binary search tree as the basis for your address book. You will also save
your address book in a text file.
Your program will appear the same as Program 1 to the user except that
it will first ask the user "Do you want to open a file? (y/n)." If the user
answers "y" the program will ask for a file name, open and read the
input file. Each pair of lines from the input file will be made an entry in
the address book: a name line and an address line. If the user answers
"n" the program will not open a file. In either case the program will
continue as did Program 1.
A new operation "save" will be added to the menu. When the user
selects "save" the program will ask the user for the name of a file in
which to write the address book, open the file and write the entire
address book to the file. This operation will be very similar to the
"displayAll()" operation.
Internals
Again, you will write (among other classes) a class Table which will
store entries comprised of (key/value) pairs of Strings. This class will
have the same public methods as did Program 1 with the addition of
a public void save() method and it will have none of the "mark" classes.
Table will now be implemented as a binary search tree. Each node will
have two String fields (for the name and address). insert, lookUp, delete,
and update will use binary search tree operations (which you will
write). You will use traversals to implement "displayAll()" and "save()".
For "displayAll()" use an in-order traversal but for "save" use either a
pre- or post-order traversal.
