ZCW-PhoneBook/PhoneBook.java

import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.SortedMap;
import java.util.TreeMap; 
import java.util.ArrayList;

public class PhoneBook {
    public TreeMap<String, ArrayList<String>> bookEntries;

    public PhoneBook (){
        this.bookEntries = new TreeMap<String, ArrayList<String>>();
    }

    public void add(String name, String phoneNumber) {
        ArrayList<String> addMe = new ArrayList<String>();
        if (bookEntries.containsKey(name)) {
            addMe = bookEntries.get(name);
        }
        addMe.add(phoneNumber);
        bookEntries.put(name, addMe);
    }

    public void remove(String name, String phoneNumber) {
        ArrayList listOfNumbers = new ArrayList();
        if (bookEntries.containsKey(name)) {
            listOfNumbers = bookEntries.get(name);
            listOfNumbers.remove(phoneNumber);
        }
        if (listOfNumbers.size() == 0) {
            bookEntries.remove(name);
        }
    }

    public void removeRecord(String name) {
        if (bookEntries.containsKey(name)) {
            bookEntries.remove(name);
        }
    }

    public String lookup(String name) {
        String phoneNumber = "This entry doesn't exist. Please enter valid entry.";
        if (bookEntries.containsKey(name)) {
            phoneNumber = bookEntries.get(name).toString().replace("[", "").replace("]", "");
        }
        return phoneNumber;
    }

    public String reverseLookup(String phoneNumber) {
        String name = "This entry doesn't exist. Please enter valid entry.";
        Set<String> keys = bookEntries.keySet();
        for(String key: keys){
            if(bookEntries.get(key).contains(phoneNumber) == true) {
                name = key;
            }
        }
        return name;
    }

    public void display() {
        Set<String> keys = bookEntries.keySet();
        for(String key: keys){
            System.out.println(key + ": " + bookEntries.get(key).toString().replace("[", "").replace("]", ""));
        }
    }

    public void main(String[] args) {
        PhoneBook myBook = new PhoneBook();
        myBook.add("Tomato", "267-945-5231");
        myBook.add("Asparagus", "305-504-1159");
        myBook.add("Eggplant", "123-345-6789");
        myBook.add("Beet", "233-464-1289");
        myBook.add("Asparagus", "454-345-4566");
        myBook.add("Leeks", "194-345-3458");
        myBook.add("Leeks", "345-209-1095");
        myBook.display();

        System.out.println("***");
        myBook.remove("Asparagus", "305-504-1159");
        myBook.removeRecord("Beet");
        System.out.println("Phonebook after removing Asparagus' number and Beets' record");
        myBook.display();

        System.out.println("***");
        System.out.println("Looking for Leeks' phone number");
        System.out.println(myBook.lookup("Leeks"));

        System.out.println("***");
        System.out.println("Looking for the owner of number 454-345-4566");
        System.out.println(myBook.reverseLookup("454-345-4566"));

        System.out.println("***");
        System.out.println("Looking for Banana's phone number");
        System.out.println(myBook.lookup("Banana"));
    }
}