ZCW-PhoneBook/PhoneBook.java

 
import java.util.TreeMap;
import java.util.Set;
import java.util.ArrayList;
/**
 * Created by leon on 1/23/18.
 * Updated by allison on 5/30/18
 */
public class PhoneBook {
    
    TreeMap<String, ArrayList<String>> myFriendsDigits;
    
    public PhoneBook() {
        myFriendsDigits = new TreeMap<String, ArrayList<String>>();
    }

    public void add(String name, String phoneNumber) {
        if (lookup(name).equals("Not Found")){
            ArrayList<String> soManyDigits = new ArrayList<String>();
            soManyDigits.add(phoneNumber);
            myFriendsDigits.put(name, soManyDigits);
        }
        else {
            ArrayList<String> soManyDigits = myFriendsDigits.get(name);
            soManyDigits.add(phoneNumber);
        }
    }
    
    public void add(String name, ArrayList<String> phoneNumbers) {
        myFriendsDigits.put(name, phoneNumbers);
    }

    public void remove(String name) {
        myFriendsDigits.remove(name);
    }
    public void remove(String name, int phoneNumberIndex) {
        ArrayList phoneNumbers = myFriendsDigits.get(name);
        phoneNumbers.remove(phoneNumberIndex);
    }
    public String lookup(String name) {
        ArrayList<String> phoneNumbers = myFriendsDigits.get(name);
        if (phoneNumbers != null) {
            return getPhoneNumberString(phoneNumbers);
        }
        else {
           return "Not Found";
        }
    }

    public String reverseLookup(String phoneNumber) {
        Set<String> names = myFriendsDigits.keySet();
        for (String name : names) {
            if (searchPhoneNumberList(myFriendsDigits.get(name), phoneNumber)){
                return name;
            }
        } 
        return "Not Found";
    }

    public void display() {
        Set<String> names = myFriendsDigits.keySet();
        for (String name : names){
            System.out.println("Name: " + name + ": " + myFriendsDigits.get(name));
        }
    }
    private boolean searchPhoneNumberList(ArrayList<String> phoneNumbers, String theMagicNumber) {
        boolean found = false;
        for (int i = 0; i < phoneNumbers.size(); i++) {
            if (phoneNumbers.get(i).equals(theMagicNumber)) {
                found = true;
                break;
            }
        }
        return found;
    }
    private String getPhoneNumberString(ArrayList<String> phoneNumbers) {
        StringBuilder formattedNumbers = new StringBuilder();
        for (int i = 0; i < phoneNumbers.size(); i++) {
           if (i == phoneNumbers.size() - 1) {
               formattedNumbers.append(phoneNumbers.get(i));
           }
           else {
               formattedNumbers.append(phoneNumbers.get(i) + ", ");
           }
        }
        return formattedNumbers.toString();
    }
}