Question

Add Instance to the Array

List Instances in an Array

Search for an Instance in the Array

Delete an Instance from the Array

Update an Instance in the Array

Save Array Elements to CSV File

Exit Program

The requirement of this assignment is to design and implement a system in Java that will manage instantiated instances of the Objects created in the User Designed Object Assignment. This is the Young Adult Object. The system should be able to add an instance of a Young Adult Object to the array, remove an instance of a Young Adult Object from the array, list all instances of Young Adult Objects in the array, Update an instance of a Young Adult object in the array and Store all instances in the array to a Comma Separated Value (CSV) File. It should also be able to load a set of starter Young Adult Objects. The task to load the starter set of objects can be a menu option or an automated process when the program starts.

The System should read data for 3 to 5 sample instances from a text file, load the data into the appropriate objects, and add the objects to the array. After loading the sample instances into the array, the system should display a menu similar to the one listed below. Your menu does not have to exactly match this one

Answer 1

Person.java

public class Person {
private String firstName, lastName, address, phone;
  
public Person()
{
this.firstName = this.lastName = this.address = this.phone = "";
}

public Person(String firstName, String lastName, String address, String phone) {
this.firstName = firstName;
this.lastName = lastName;
this.address = address;
this.phone = phone;
}

public String getFirstName() {
return firstName;
}

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

public String getLastName() {
return lastName;
}
  
public String getName(){ return(getFirstName() + " " + getLastName()); }

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

public String getAddress() {
return address;
}

public void setAddress(String address) {
this.address = address;
}

public String getPhone() {
return phone;
}

public void setPhone(String phone) {
this.phone = phone;
}
  
public String strToFile()
{
return(firstName + "," + lastName + "," + address + "," + phone);
}
  
@Override
public String toString()
{
return("Name: " + getFirstName() + " " + getLastName() + ", Address: " + getAddress() + ", Phone: " + getPhone());
}
}

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<Person> people;
  
public AddressBook()
{
this.people = new ArrayList<>();
}
  
public void readFile(String filename)
{
Scanner fileReader;
try
{
fileReader = new Scanner(new File(filename));
while(fileReader.hasNextLine())
{
String[] data = fileReader.nextLine().trim().split(",");
String firstName = data[0];
String lastName = data[1];
String address = data[2];
String phone = data[3];
people.add(new Person(firstName, lastName, address, phone));
}
fileReader.close();
}catch(FileNotFoundException fnfe){
System.out.println(filename + " could not be found! Exiting..");
System.exit(0);
}
}
  
public void writeFile(String filename)
{
FileWriter fw;
PrintWriter pw;
try {
fw = new FileWriter(new File(filename));
pw = new PrintWriter(fw);
for(Person p : people)
pw.write(p.strToFile() + System.lineSeparator());
  
pw.flush();
fw.close();
pw.close();
System.out.println("Address book has been saved to " + filename + ".\n");
} catch (IOException ex) {
System.out.println("Error in writing data to " + filename + "! Exiting..");
System.exit(0);
}
}
  
private int indexOf(String name)
{
int index = -1;
for(int i = 0; i < people.size(); i++)
{
if(people.get(i).getFirstName().equalsIgnoreCase(name))
{
index = i;
break;
}
}
return index;
}
  
public void addPerson()
{
Scanner sc = new Scanner(System.in);
System.out.print("Enter the first name: ");
String firstName = sc.nextLine().trim();
int index = indexOf(firstName);
if(index == -1)
{
System.out.print("Enter the last name: ");
String lastName = sc.nextLine().trim();
System.out.print("Enter the address: ");
String address = sc.nextLine().trim();
System.out.print("Enter the phone number: ");
String phone = sc.nextLine().trim();
people.add(new Person(firstName, lastName, address, phone));
System.out.println(firstName + " is added to the address book successfully.\n");
}
else
System.out.println(firstName + " is already added to the address book!\n");
}
  
public void removePerson()
{
if(people.isEmpty())
{
System.out.println("List is empty!\n");
return;
}
Scanner sc = new Scanner(System.in);
System.out.print("Enter the first name: ");
String firstName = sc.nextLine().trim();
int index = indexOf(firstName);
if(index == -1)
System.out.println("Sorry, no such person found!\n");
else
{
people.remove(index);
System.out.println(firstName + " is removed from the address book successfully.\n");
}
}
  
public void searchPerson()
{
if(people.isEmpty())
{
System.out.println("List is empty!\n");
return;
}
Scanner sc = new Scanner(System.in);
System.out.print("Enter the first name: ");
String firstName = sc.nextLine().trim();
int index = indexOf(firstName);
if(index == -1)
System.out.println("Sorry, no such person found!\n");
else
{
System.out.println("Match found:\n" + people.get(index) + "\n");
}
}
  
public void updatePerson()
{
if(people.isEmpty())
{
System.out.println("List is empty!\n");
return;
}
Scanner sc = new Scanner(System.in);
System.out.print("Enter the first name: ");
String firstName = sc.nextLine().trim();
int index = indexOf(firstName);
if(index == -1)
System.out.println("Sorry, no such person found!\n");
else
{
System.out.println("Provide new information for " + people.get(index).getName() + ":");
System.out.print("Enter new address: ");
String newAddress = sc.nextLine().trim();
System.out.print("Enter new phone: ");
String newPhone = sc.nextLine().trim();
people.get(index).setAddress(newAddress);
people.get(index).setPhone(newPhone);
System.out.println("Information for " + people.get(index).getName() + " is successfully updated.\n");
}
}
  
public void displayAll()
{
if(people.isEmpty())
{
System.out.println("List is empty!\n");
return;
}
for(Person p : people)
System.out.println(p);
System.out.println();
}
}

Main.java (Main class)

import java.util.Scanner;

public class Main {
  
private static final String FILENAME = "my_address_book.txt";
  
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
AddressBook book = new AddressBook();
book.readFile(FILENAME);
int choice;
do
{
displayMenu();
choice = Integer.parseInt(sc.nextLine().trim());
switch(choice)
{
case 1:
{
System.out.println("\nADD A PERSON:\n"
+ "-------------");
book.addPerson();
break;
}
case 2:
{
System.out.println("\nREMOVE A PERSON:\n"
+ "----------------");
book.removePerson();
break;
}
case 3:
{
System.out.println("\nSEARCH A PERSON:\n"
+ "----------------");
book.searchPerson();
break;
}
case 4:
{
System.out.println("\nUPDATE A PERSON:\n"
+ "----------------");
book.updatePerson();
break;
}
case 5:
{
System.out.println("\nDISPLAY ALL PEOPLE:\n"
+ "-------------------");
book.displayAll();
break;
}
case 0:
{
book.writeFile(FILENAME);
System.out.println("\nThanks..Goodbye!\n");
System.exit(0);
}
default:
System.out.println("\nInvalid selection!\n");
}
}while(choice != 0);
}
  
private static void displayMenu()
{
System.out.print("Choose from the following options:\n"
+ "1. Add a person\n"
+ "2. Remove a person\n"
+ "3. Search a person\n"
+ "4. Update a person\n"
+ "5. Display all people\n"
+ "0. Exit\n"
+ "Your selection >> ");
}
}

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

INPUT FILE (my_address_book.txt) - This file needs to be created before running the code and this file should be created within the same working directory where the above .java files will be residing.

CONSOLE OUTPUT :