Question

Requirements Create an Address Book class in Java for general use with the following behaviors: 1. Constructor: public Address Book Construct a new address book object. • A contact has four fields: first name, last name, email and phone. (There could be more information for a real contact. But these are sufficient for the assignment.) . The constructor reads from the disk to retrieve previously entered contacts. If previous contacts exist, the address book will be populated with those contacts retrieved from the disk. Otherwise, the address book will be empty. . The constructor should notify the user if any disk I/O error occurs (IOException). Note: Since the Address Book class should not include the user interface, the way in which the user is notified should be a correspondingly thrown exception object. A System.out.println() is NOT appropriate for this method.

Answer 1

EmptyNameException.java

public class EmptyNameException extends Exception{
  
public EmptyNameException(String msg)
{
super(msg);
}
}

ContactNotFoundException.java

public class ContactNotFoundException extends Exception{
  
public ContactNotFoundException(String msg)
{
super(msg);
}
}

DuplicateContactException.java

public class DuplicateContactException extends Exception{
  
public DuplicateContactException(String msg)
{
super(msg);
}
}

Contact.java

public class Contact {
  
private String firstName, lastName, email, phone;
  
public Contact()
{
this.firstName = this.lastName = this.email = this.phone = "";
}
  
public Contact(String firstName, String lastName) throws EmptyNameException
{
if(firstName.equals("") || firstName.trim().equals("") || lastName.equals("") || lastName.trim().equals(""))
throw new EmptyNameException("First/Last name cannot be empty!");
  
this.firstName = firstName;
this.lastName = lastName;
this.email = this.phone = "";
}

public Contact(String firstName, String lastName, String email, String phone) {
this.firstName = firstName;
this.lastName = lastName;
this.email = email;
this.phone = phone;
}

public String getFirstName() {
return firstName;
}

public void setFirstName(String firstName) {
this.firstName = firstName;
}

public String getLastName() {
return lastName;
}

public void setLastName(String lastName) {
this.lastName = lastName;
}

public String getEmail() {
return email;
}

public void setEmail(String email) {
this.email = email;
}

public String getPhone() {
return phone;
}

public void setPhone(String phone) {
this.phone = phone;
}
  
@Override
public String toString()
{
return("Name: " + this.firstName + " " + this.lastName + ", Email: " + this.email + ", Phone: " + this.phone);
}
  
public boolean equals(Contact other)
{
return (this.firstName.equalsIgnoreCase(other.getFirstName()) &&
this.lastName.equalsIgnoreCase(other.getLastName()));
}
}

AddressBook.java

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Scanner;

public class AddressBook {
private ArrayList<Contact> contacts;
private static final String FILE = "contacts.dat";
  
public AddressBook()
{
this.contacts = new ArrayList<>();
  
// reads input file and populate all contacts to the list
Scanner fileReader;
try
{
fileReader = new Scanner(new File(FILE));
while(fileReader.hasNextLine())
{
String line = fileReader.nextLine().trim();
String[] data = line.split(",");
String firstName = data[0];
String lastName = data[1];
String email = data[2];
String phone = data[3];
  
this.contacts.add(new Contact(firstName, lastName, email, phone));
}
fileReader.close();
}catch(FileNotFoundException fnfe){
System.exit(1);
}
}
  
public void addContact(Contact newContact) throws EmptyNameException, DuplicateContactException, IOException
{
if(newContact.getFirstName().equals("") || newContact.getFirstName().trim().equals("")
|| newContact.getLastName().equals("") || newContact.getLastName().trim().equals(""))
throw new EmptyNameException("First/Last name cannot be empty!");
  
for(Contact con : this.contacts)
{
if(con.equals(newContact))
throw new DuplicateContactException(("Duplicate contact found!"));
}
  
this.contacts.add(newContact);
saveContactsToDisk();
}
  
private void saveContactsToDisk() throws IOException
{
FileWriter fw;
PrintWriter pw;
  
fw = new FileWriter(new File(FILE));
pw = new PrintWriter(fw);
  
for(Contact con : this.contacts)
{
pw.write(con.getFirstName() + "," + con.getLastName() + "," + con.getEmail() + "," + con.getPhone()
+ System.lineSeparator());
}
  
pw.flush();
fw.close();
pw.close();
}
  
public void deleteContact(String firstName, String lastName) throws EmptyNameException, ContactNotFoundException, IOException
{
if(firstName.equals("") || firstName.trim().equals("") || lastName.equals("") || lastName.trim().equals(""))
throw new EmptyNameException(("First/Last name cannot be empty!"));
  
int index = -1;
boolean found = false;
for(int i = 0; i < this.contacts.size(); i++)
{
if(this.contacts.get(i).getFirstName().equalsIgnoreCase(firstName) &&
this.contacts.get(i).getLastName().equalsIgnoreCase(lastName))
{
found = true;
index = i;
break;
}
}
  
if(!found)
throw new ContactNotFoundException("No contact with name " + firstName + " " + lastName + " were found!");
  
// contact found at index
this.contacts.remove(index);
saveContactsToDisk();
}
  
public Contact[] searchByLastName(String lastName) throws EmptyNameException
{
if(lastName.equals("") || lastName.trim().equals(""))
throw new EmptyNameException(("First/Last name cannot be empty!"));
  
ArrayList<Contact> searchedContacts = new ArrayList<>();
  
for(int i = 0; i < this.contacts.size(); i++)
{
if(this.contacts.get(i).getLastName().equalsIgnoreCase(lastName))
searchedContacts.add(this.contacts.get(i));
}
  
return (Contact[]) searchedContacts.toArray(new Contact[0]);
}
  
public Contact[] list()
{
return (Contact[]) this.contacts.toArray(new Contact[0]);
}
  
public Contact[] searchByLastNamePartial(String partialLastName) throws EmptyNameException
{
if(partialLastName.equals("") || partialLastName.trim().equals(""))
throw new EmptyNameException(("First/Last name cannot be empty!"));
  
ArrayList<Contact> searchedContacts = new ArrayList<>();
  
for(int i = 0; i < this.contacts.size(); i++)
{
if(this.contacts.get(i).getLastName().contains(partialLastName))
searchedContacts.add(this.contacts.get(i));
}
  
return (Contact[]) searchedContacts.toArray(new Contact[0]);
}
}

AddressBookTester.java (Main class)

import java.io.IOException;

public class AddressBookTester {
  
public static void main(String[] args)
{
System.out.println("Attempting to read disk for contacts..");
AddressBook addressBook = new AddressBook();
  
System.out.println("\nDisplaying all contacts read from disk..");
for(int i = 0; i < addressBook.list().length; i++)
{
System.out.println(addressBook.list()[i]);
}
  
System.out.println("\nAttempting to add an empty Contact..");
try {
addressBook.addContact(new Contact(" ", " ", "alice@hotmail.com", "445698712"));
} catch (EmptyNameException | DuplicateContactException | IOException ex) {
System.out.println(ex.getMessage());
}
  
System.out.println("\nAttempting to add a duplicate Contact..");
try {
addressBook.addContact(new Contact("Alice", "Stuart", "alice@hotmail.com", "445698712"));
} catch (EmptyNameException | DuplicateContactException | IOException ex) {
System.out.println(ex.getMessage());
}
  
System.out.println("\nAttempting to add a new Contact..");
try {
addressBook.addContact(new Contact("Alakha", "Measil", "alakmeas@rediffmail.com", "1169987231"));
} catch (EmptyNameException | DuplicateContactException | IOException ex) {
System.out.println(ex.getMessage());
}
System.out.println("Displaying all contacts read from disk..");
for(int i = 0; i < addressBook.list().length; i++)
{
System.out.println(addressBook.list()[i]);
}
  
System.out.println("\nAttempting to delete a contact not present..");
try {
addressBook.deleteContact("Wannah", "Halfboy");
} catch (EmptyNameException | ContactNotFoundException | IOException ex) {
System.out.println(ex.getMessage());
}
  
System.out.println("\nAttempting to delete a contact present (Alice Stuart)..");
try {
addressBook.deleteContact("Alice", "Stuart");
} catch (EmptyNameException | ContactNotFoundException | IOException ex) {
System.out.println(ex.getMessage());
}
System.out.println("Displaying all contacts read from disk..");
for(int i = 0; i < addressBook.list().length; i++)
{
System.out.println(addressBook.list()[i]);
}
  
System.out.println("\nAttempting to search contacts by last name (Weasely)..");
try {
for(int i = 0; i < addressBook.searchByLastName("Weasely").length; i++)
{
System.out.println(addressBook.searchByLastNamePartial("Weasely")[i]);
}
} catch (EmptyNameException ex) {
System.out.println(ex.getMessage());
}
  
System.out.println("\nAttempting to search contacts by partial last name (son)..");
try {
for(int i = 0; i < addressBook.searchByLastNamePartial("son").length; i++)
{
System.out.println(addressBook.searchByLastNamePartial("son")[i]);
}
} catch (EmptyNameException ex) {
System.out.println(ex.getMessage());
}
}
}

******************************************************************** SCREENSHOT *******************************************************

run: Attempting to read disk for contacts.. Displaying all contacts read from disk.. Name: Henry Johnson, Email: hj@hotmail.com, Phone: 113695564 Name: Alice Stuart, Email: alice@hotmail.com, Phone: 144986321 Name: Max Jefferson, Email: maxx@rediffmail.com, Phone: 993114561 Name: Robert McKinely, Email: robert_fury@hotmail.com, Phone: 223618764 Name: Hannah Weasely, Email: weasleythefairy@rediffmail.com, Phone: 112534899 Attempting to add an empty Contact.. First/Last name cannot be empty! Attempting to add a duplicate Contact.. Duplicate contact found! Attempting to add a new contact.. Displaying all contacts read from disk.. Name: Henry Johnson, Email: hj@hotmail.com, Phone: 113695564 Name: Alice Stuart, Email: alice@hotmail.com, Phone: 144986321 Name: Max Jefferson, Email: maxx@rediffmail.com, Phone: 993114561 Name: Robert McKinely, Email: robert fury@hotmail.com, Phone: 223618764 Name: Hannah Weasely, Email: weasleythefairy@rediffmail.com, Phone: 112534899 Name: Alakha Measil, Email: alakmeas@rediffmail.com, Phone: 1169987231 Attempting to delete a contact not present.. No contact with name Wannah Halfboy were found! Attempting to delete a contact present (Alice Stuart).. Displaying all contacts read from disk.. Nama Dan Tobno m . 5abotm o m Dbane 112 GALEGA

STOCROTESTETICA moy m oyonova CroTTEOTECTIEDOT Attempting to add an empty Contact.. First/Last name cannot be empty! Attempting to add a duplicate Contact.. Duplicate contact found! Attempting to add a new contact.. Displaying all contacts read from disk.. Name: Henry Johnson, Email: hj@hotmail.com, Phone: 113695564 Name: Alice Stuart, Email: alice@hotmail.com, Phone: 144986321 Name: Max Jefferson, Email: maxx@rediffmail.com, Phone: 993114561 Name: Robert McKinely, Email: robert_fury@hotmail.com, Phone: 223618764 Name: Hannah Weasely, Email: weasleythefairy@rediffmail.com, Phone: 112534899 Name: Alakha Measil, Email: alakmeas@rediffmail.com, Phone: 1169987231 Attempting to delete a contact not present.. No contact with name Wannah Halfboy were found! Attempting to delete a contact present (Alice Stuart).. Displaying all contacts read from disk.. Name: Henry Johnson, Email: hj@hotmail.com, Phone: 113695564 Name: Max Jefferson, Email: maxx@rediffmail.com, Phone: 993114561 Name: Robert McKinely, Email: robert_fury@hotmail.com, Phone: 223618764 Name: Hannah Weasely, Email: weasleythefairy@rediffmail.com, Phone: 112534899 Name: Alakha Measil, Email: alakmeas@rediffmail.com, Phone: 1169987231 Attempting to search contacts by last name (Weasely).. Name: Hannah Weasely, Email: weasleythefairy@rediffmail.com, Phone: 112534899 Attempting to search contacts by partial last name (son).. Name: Henry Johnson, Email: hj@hotmail.com, Phone: 113695564 Name: Max Jefferson, Email: maxx@rediffmail.com, Phone: 993114561 BUILD SUCCESSFUL (total time: 0 seconds)

CONTACTS FILE (contacts.dat)

Contact.javax AddressBook.java * AddressBookTester.java x contacts.dat x Source History ... Q EDTB D O O Henry, Johnson, hi@hotmail.com, 113695564 Max, Jefferson, maxx@rediffmail.com, 993114561 Robert, McKinely fobert_fury@hotmail.com, 223618764 Hannah, Weasely, weasleythefairy@rediffmail.com, 112534 899 Alakha, Measit, alakmeas@rediffmail.com, 1169987231