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Java adding from multiple classes with an interface

Based on the following UML class diagram I am trying to get the total population of all the House and ApartmentBuilding objects using an interface (Dwelling) and I am stuck on how to proceed. I have included the code I have so far.
Dwelling:
interface Dwelling {
int getNumberOfOccupants();
}
House:
import javafx.scene.canvas.GraphicsContext;
import java.util.Scanner;
public class House extends Building implements Dwelling {
private final int bedrooms;
private final int occupants;
private House(String name, double xPosition,int bedrooms, int occupants){
super(name,xPosition);
this.bedrooms = bedrooms;
this.occupants = occupants;
}
public static House create() {
Scanner scan = new Scanner(System.in);
House a;
System.out.println("Enter name of the House: ");
String name = scan.nextLine();
System.out.println("Enter XPosition of the House: ");
int xPosition = scan.nextInt();
System.out.println("Enter number of bedrooms: ");
int bedrooms = scan.nextInt();
System.out.println("Enter number of occupants: ");
int occupants = scan.nextInt();
a = new House(name, xPosition, bedrooms, occupants);
return a;
}
public void draw(GraphicsContext canvas){
}
#Override
public String toString(){
return "House: " + "bedrooms= " + bedrooms + " occupants= " + occupants + "\n" + super.toString();
}
#Override
public int getNumberOfOccupants() {
return occupants;
}
}
ApartmentBuilding:
import javafx.scene.canvas.GraphicsContext;
import java.util.Scanner;
public class ApartmentBuilding extends HighRise implements Dwelling{
private final int occupantsPerFloor;
private ApartmentBuilding(String name, double xPosition, int numberOfFloors, int occupantsPerFloor){
super(name, xPosition, numberOfFloors);
this.occupantsPerFloor = occupantsPerFloor;
}
public static ApartmentBuilding create() {
Scanner scan = new Scanner(System.in);
ApartmentBuilding a;
System.out.println("Enter name of the Apartment Building: ");
String name = scan.nextLine();
System.out.println("Enter XPosition of the Apartment Building: ");
int xPosition = scan.nextInt();
System.out.println("Enter number of floors: ");
int numberOfFloors = scan.nextInt();
System.out.println("Enter number of occupants per floor: ");
int occupantsPerFloor = scan.nextInt();
a = new ApartmentBuilding(name, xPosition, numberOfFloors, occupantsPerFloor);
return a;
}
public void draw(GraphicsContext canvas){
}
#Override
public String toString(){
return "Apartment Building: " + "occupantsPerFloor= " + occupantsPerFloor + "\n" + super.toString() + "\n";
}
#Override
public int getNumberOfOccupants() {
return numberOfFloors * occupantsPerFloor;
}
}
Building:
import javafx.scene.canvas.GraphicsContext;
public class Building implements Drawable {
private final String name;
private final double xPosition;
public Building(String name, double xPosition){
this.name = name;
this.xPosition = xPosition;
}
public String getName(){
return name;
}
public void draw(GraphicsContext canvas) {
}
public double getXPosition() {
return xPosition;
}
#Override
public String toString(){
return "Type... Building: " + "name= " + getName() + ", xPosition= " + getXPosition() + "\n";}
}
HighRise:
public class HighRise extends Building{
int numberOfFloors;
public HighRise(String name, double xPosition, int numberOfFloors) {
super(name, xPosition);
this.numberOfFloors=numberOfFloors;
}
public int getNumberOfFloors(){
return numberOfFloors;
}
#Override
public String toString() {
return "Type... HighRise: " + "numberOfFloors= " + getNumberOfFloors() + "\n" + super.toString();
}
}
Village:
import javafx.scene.canvas.GraphicsContext;
import java.util.Scanner;
public class Village extends Building{
private static String name;
private static int xPosition;
public static final double Y_FLOOR = 300;
private int size;
private final String villageName;
private final Building[] buildings;
private Village(String villageName, int size){
super(name, xPosition);
this.size = size;
this.villageName = villageName;
this.buildings = new Building[size];
}
public static Village create() {
Scanner scan = new Scanner(System.in);
Village a;
System.out.println("Enter name of village: ");
String villageName = scan.nextLine();
System.out.println("Enter number of buildings: ");
int num = scan.nextInt();
a = new Village(villageName, num);
for(int i = 0; i < num; i++) {
System.out.println("Enter type of Building: 1= House, 2= Apartment, 3= Store ");
int choice = scan.nextInt();
if (choice == 1){
a.buildings[i] = House.create();
}
if (choice == 2){
a.buildings[i] = ApartmentBuilding.create();
}
}
return a;
}
public int getPopulation(){
return size;
}
public void draw(GraphicsContext canvas){
}
public String toString(){
String str = "\n"+ "Village of " + villageName + "\n\n";
for (int i=0; i<buildings.length; i++) {
str = str + buildings[i].toString() + "\n"; // this adds each buildings information to the string
}
return str;
}
}
I am new at programming and trying my best to learn but I am getting stuck on this, unfortunately.

..I am trying to get the total population of all the House and ApartmentBuilding objects using an interface (Dwelling)..
You can not get the population while using that UML. Please try modify a bit as below.
First, Dwelling must declaire getPopulation();
Implementing getPopulation() within House and ApartmentBuilding
You need a variable to keep the population within House and ApartmentBuilding class as well (it will be returned while calling getPopulation()).
After that, you able to cast House and ApartmentBuilding to Dwelling. Then dwelling.getPopulation(). Hope it is useful.

How do i clear screen?

After user enter Status and enter how can i make everything on the top disappear and just show whatever's below that. I do want the inputs to be visible anymore. How can i implement this? Can someone help me fix my code, I previously tried a system out flush but it did not work. Thank you very much.
package com.company;
import java.util.ArrayList;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
ArrayList<Car> cars = new ArrayList<>();
int choice;
Car car = new Car();
Scanner scanner = new Scanner(System.in);
while (true){
System.out.println("\n1 - Insert car\n2 - Edit car\n3 - Exit");
System.out.println("Enter your choice: ");
choice = scanner.nextInt();
switch (choice){
case 1:
car = new Car();
scanner = new Scanner(System.in);
System.out.println("Enter Plate number: ");
car.setPlateNumber(scanner.nextLine());
System.out.println("Enter Brand: ");
car.setBrand(scanner.nextLine());
System.out.println("Enter Model: ");
car.setModel(scanner.nextLine());
System.out.println("Enter type: ");
car.setType(scanner.nextLine());
System.out.println("Enter Color: ");
car.setColour(scanner.nextLine());
System.out.println("Enter Price: ");
car.setPrice(scanner.nextDouble());
scanner = new Scanner(System.in);
System.out.println("Enter Status: ");
car.setStatus(scanner.nextLine());
cars.add(car);
System.out.println("\nCar saved successfully!!");
break;
case 2:
car = new Car();
scanner = new Scanner(System.in);
System.out.println("Enter car Plate Number: ");
car.setPlateNumber(scanner.nextLine());
if(!car.editCarRecord(cars))
System.out.println("Car not found!!");
break;
case 3:
return;
default:
System.out.println("Invalid option!!");
}
}
}
}
package com.company;
import java.util.ArrayList;
import java.util.Scanner;
public class Car {
private String plateNumber;
private String brand;
private String model;
private String type;
private String colour;
private String status;
private double price;
public Car() {
// Define this if we want default values
}
public Car(String pn, String br, String mo, String ty, String co, String st, double pr) {
plateNumber = pn;
brand = br;
model = mo;
type = ty;
colour = co;
status = st;
price = pr;
}
public void setPlateNumber(String pn) {
plateNumber = pn;
}
public void setBrand(String br) {
brand = br;
}
public void setModel(String mo) {
model = mo;
}
public void setType(String ty) {
type = ty;
}
public void setColour(String co) {
colour = co;
}
public void setStatus(String st) {
status = st;
}
public void setPrice(double pr) {
price = pr;
}
public String getPlateNumber() {
return plateNumber;
}
public String getBrand() {
return brand;
}
public String getModel() {
return model;
}
public String getType() {
return type;
}
public String getColour() {
return colour;
}
public String getStatus() {
return status;
}
public double getPrice() {
return price;
}
public boolean editCarRecord(ArrayList<Car> list){
Scanner scanner = new Scanner(System.in);
int choice;
for(int i=0; i<list.size(); i++) {
if (list.get(i).getPlateNumber().compareToIgnoreCase(this.getPlateNumber()) == 0) {
System.out.println("Car record matched!!");
System.out.println(list.get(i).toString());
while(true) {
System.out.println("1 - Edit Status\n2 - Edit Price\n3 - Edit Color\n4 - Back to main menu");
System.out.println("Enter your choice: ");
choice = scanner.nextInt();
if (choice == 1) {
System.out.println("Enter new Status: ");
list.get(i).setStatus(scanner.nextLine());
System.out.println("Status updated Successfully!");
} else if (choice == 2) {
System.out.println("Enter new Price: ");
list.get(i).setPrice(scanner.nextDouble());
System.out.println("Price updated Successfully!");
} else if (choice == 3) {
System.out.println("Enter new Color: ");
list.get(i).setColour(scanner.nextLine());
System.out.println("Color updated Successfully!");
} else if (choice == 4) {
return true;
} else {
System.out.println("Invalid choice!!");
}
}
}
}
return false;
}
public String toString() {
return "Plate number: " + plateNumber
+ "\nBrand: " + brand
+ "\nModel: " + model
+ "\nType: " + type
+ "\nColour: " + colour
+ "\nStatus: " + status
+ "\nPrice: " + price;
}
}

Difficulty setting and updating objects in a Sorted ArrayList [duplicate]

This question already has answers here:
method in class cannot be applied to given types
(7 answers)
Closed 2 years ago.
I wish to be able to update information about objects entered by a user. I would like the user to enter a book name and user name to take out the book, as well as being able to return it with the same information. The objects have to be inserted into the right place in my sortedarraylists. Each user is assumed to be unique and each book can only be taken out by one user (who can take out up to 3 books).
When I try to compile my code, I get this error message:
java: method issueBook in class Driver cannot be applied to given types;
required: Book,User
found: no arguments
reason: actual and formal argument lists differ in length
This corresponds to issueBook(); in case i of my menu.
I also have User and Book classes that implement Comparable<Book> etc. I tried to omit as much irrelevant code as I could, such as the filereader to scan in new user and book objects. I included the book and user classes in case they need to be looked at (I think they are mostly fine). Please let me know if you need any more details however.
import java.io.*;
import java.util.Scanner;
public class Driver {
static Scanner sc = new Scanner(System.in);
private static void mainMenu() {
System.out.println("------------------------------\n"+
"f: Finish running the program\n" +
"b -Display on the screen the information about all the books in the library\n" +
"u -Display on the screen the information about all the users.\n" +
"i -Update the stored data when a book is issued to a user\n" +
"r -Update the stored data when a user returns a book to the library\n" +
"------------------------------\n" +
"Type a letter and press Enter\n");
}
private static User readNames() throws User.InvalidBookLimitException {
System.out.println("Enter the user's firstname: ");
String firstName = sc.next();
System.out.println("Enter the user's surname: ");
String surName = sc.next();
sc.nextLine(); //TODO check this
return new User(firstName, surName, 0);
}
private static User readUserData(User user) throws User.InvalidBookLimitException {
User u = readNames();
System.out.println("Enter " + user + "'s age, and press Enter");
int numberOfBooks = sc.nextInt();
sc.nextLine();
return new User(u.getFirstName(), u.getSurName(),u.getNumberOfBooks());
}
private static Book readBookName (){
System.out.println("Type in the name of the book");
String bookName = sc.nextLine();
return new Book(bookName);
}
/* public SortedArrayList<User> sortedUsers = new SortedArrayList<>(); public SortedArrayList<Book> sortedBooks = new SortedArrayList<>();*/
//If this part is commented out, I get errors since I can't seem to access the arraylists in the
// main method for the issueBook/returnBook methods.
public void issueBook(Book book, User user){
for (Book b : sortedBooks){
if(b.equals(book)){
b.loanStatus(true);
/*b.setLoanerNames(user);*/ b.setLoanerNames("John", "Doe");
break;
}
}
for (User u: sortedUsers){
if(u.equals(user)){
u.setNumberOfBooks(u.getNumberOfBooks()+1);
}
}
}
public void returnBook(Book book, User user){
for (Book b : sortedBooks){
if(b.equals(book)){
b.loanStatus(false);
b.setLoanerNames(null, null);
break;
} for (User u: sortedUsers){
if(u.equals(user)){
u.setNumberOfBooks(u.getNumberOfBooks()-1);
}
}
}
}
public static <E> void main(String[] args) throws FileNotFoundException, User.InvalidBookLimitException {
//These SortedArrayLists have been derived from the sorted arraylist class
SortedArrayList<User> sortedUsers = new SortedArrayList<>();
SortedArrayList<Book> sortedBooks = new SortedArrayList<>();
mainMenu(); //main menu printing method
char ch = sc.next().charAt(0);
sc.nextLine();
while (ch !='f') //the program ends as desired if f is pressed
{ switch(ch){
case 'b':
System.out.println("Displaying information about all books in the library: ");
/*for (Object item : sortedBooks) {
System.out.println(sortedBooks.toString());
}*/
System.out.println(sortedBooks/*.toString()*/);
break;
case 'u':
System.out.println("Displaying information about all users");
System.out.println(sortedUsers/*.toString()*/);
break;
case 'i':
System.out.println("Enter the loaning out data. ");
System.out.println("Enter the user's first name and surname: ");
readNames();
System.out.println("Enter the name of the book: ");
readBookName();
issueBook();
or maybe if(u1.compareTo(u2) == 0)*/
break;
case 'r':
System.out.println("Please the details of the book to be returned: ");
/*Book b = new Book("test1", "test2", true, "lol","lol2");*/
//this was just a test and didn't work
/*returnBook(b);*/
break;
default:
System.out.println("Invalid input, please enter f, b, i or r");
}
mainMenu();
ch = sc.next().charAt(0);
sc.nextLine();
}
}
}
My sorted arraylist class with a (working) insert method:
import java.util.ArrayList;
public class SortedArrayList<E extends Comparable<E>> extends ArrayList<E> {
//no need for a generic in the insert method as this has been declared in the class
public void insert(E value) {
if (this.size() == 0) {
this.add(value);
return; }
for (int i = 0; i < this.size(); i++) {
int comparison = value.compareTo((E) this.get(i));
if (comparison < 0) {
this.add(i, value);
return; }
if (comparison == 0) {
return; }
}
this.add(value);
}
User class:
import java.io.PrintWriter;
public class User implements Comparable<User> {
private String firstName;
private String surName;
private int numberOfBooks;
public User(){
firstName = "";
surName = "";
numberOfBooks = 0;
}
public class InvalidBookLimitException extends Exception{
public InvalidBookLimitException(){
super("Invalid number of books");
}
}
public User(String name1, String name2, int books) throws InvalidBookLimitException {
this.firstName = name1;
this.surName = name2;
if (books>3) throw new InvalidBookLimitException ();
this.numberOfBooks = books;
}
public String getFirstName() {
return firstName;
}
public String getSurName(){
return surName;
}
public int getNumberOfBooks(){
return numberOfBooks;
}
public boolean borrowMoreBooks(){
return numberOfBooks < 3;
}
public void setNumberOfBooks(int numberOfBooks){
this.numberOfBooks=numberOfBooks;
}
public void setUser(String name1, String name2, int books){
firstName = name1;
surName = name2;
numberOfBooks = books;
}
public boolean userNameTest (User otherUser){
return (firstName.equals(otherUser.firstName) && surName.equals(otherUser.surName));
}
/* public boolean loanAnotherBook(){
return !(numberOfBooks<3);
numberOfBooks++;
}*/
public void printName(PrintWriter f){f.println(firstName+ " " + surName);}
/*
public void setUser(User user) {
if (loanStatus == false){
loanStatus = Driver.readNameInput();
loanStatus = true;
}
}*/
#Override
public String toString(){
return "Name: " + firstName + " " + surName + " | Number of books: " + numberOfBooks;
}
public int compareTo(User u) {
/* int snCmp = surName.compareTo(u.surName);
if (snCmp != 0)
return snCmp;
else{
int fnCmp = firstName.compareTo(u.firstName);
if (fnCmp !=0)
return fnCmp;
}*/
int fnCmp = firstName.compareTo(u.firstName);
if (fnCmp != 0) return fnCmp;
int snCmp= surName.compareTo(u.surName);
if (snCmp !=0) return snCmp;
else return numberOfBooks -u.numberOfBooks;
}
#Override
public boolean equals(Object obj) {
return super.equals(obj);
}
}
Book class:
public class Book implements Comparable<Book>{
public String bookName;
public String authorName;
public boolean loanStatus;
public String loanerFirstName;
public String loanerSurName;
//if boolean loanStatus == true private string loaner name
public Book(){
bookName = "";
authorName = "";
loanStatus = false;
loanerFirstName = null;
loanerSurName = null;
}
Book(String book, String author, boolean loanStatus, String loanerFirstName, String loanerSurName) {
this.bookName = book;
this.authorName = author;
this.loanStatus = loanStatus;
this.loanerFirstName = loanerFirstName;
this.loanerSurName = loanerSurName;
}
Book(String book){
this.bookName=book;
}
public String getBookName(){
return bookName;
}
public String getAuthorName(){
return bookName;
}
public boolean getLoanStatus(){
return loanStatus;
}
public String getLoanerFirstName(){
return loanerFirstName;
}
public String getLoanerSurName(){
return loanerSurName;
}
public void setBook(String book, String author, boolean loanStatus, String loanerFirstName, String loanerSurName){
bookName = book;
authorName = author;
loanStatus = loanStatus;
loanerFirstName = loanerFirstName;
loanerSurName = loanerSurName;
}
public void setBookName(String bookName){
this.bookName=bookName;
}
public void loanStatus(boolean loanStatus){
this.loanStatus=loanStatus;
}
public void setLoanerNames(String loanerFirstName, String loanerSurName){
this.loanerFirstName=loanerFirstName;
this.loanerSurName=loanerSurName;
}
/* public boolean nameTest (User otherUser){
return (loanerFirstName.equals(otherUser.loanerFirstName)&& loanerSurName.equals(otherUser.loanerSurName));
}
*/
public String toString(){
return "Book: " + bookName + " | Author: " + authorName + " | Loan status: " + loanStatus + " | Loaned to: " + loanerFirstName + " " + loanerSurName ;
}
//this may be redundant TODO
/* public void setLoanStatus(User user){
loanStatus = false;
}*/
//This compare method allows new user objects to be compared to ones in the
#Override //sortedArrayList, enabling the insertion method.
public int compareTo(Book b) {
int bnCmp = bookName.compareTo(b.bookName);
if (bnCmp != 0) return bnCmp;
int anCmp= authorName.compareTo(b.authorName);
if (anCmp !=0) return anCmp;
// int lsCmp= loanStatus.(b.loanStatus);
// if (lsCmp !=0) return lsCmp;
int lrfnCmp =loanerFirstName.compareTo(b.loanerFirstName);
if (lrfnCmp !=0) return lrfnCmp;
int lrlnCmp =loanerSurName.compareTo(b.loanerSurName);
if (lrlnCmp !=0) return lrlnCmp;
else return 0;
}
}

User user = readNames();
Book book = readBookName();
issueBook(book, user);
You have to pass the user and book which you have created while calling the issueBook method.

Displaying inputs using methods in java

I copied this code in a book I found in the internet about Data Structures and Algorithm in Java. This is the code:
//GameEntry Class
public class GameEntry
{
protected String name;
protected int score;
public GameEntry(String n, int s) {
name = n;
score = s;
}
public String getName() { return name; }
public int getScore() { return score; }
public String toString() {
return "(" + name + ", " + score + ")";
}
}
//Scores Class
public class Scores
{
public static final int maxEntries = 10;
protected int numEntries;
protected GameEntry[] entries;
public Scores(){
entries = new GameEntry[maxEntries];
numEntries = 3;
}
public String toString() {
String s = "[";
for(int i=0; i<numEntries; i++) {
if(i > 0) {
s = s + ", ";
}
s = s + entries[i];
}
return s + "]";
}
public static void main(String[] args){
Scanner input = new Scanner(System.in);
Scores s = new Scores();
for(int i=0; i<s.numEntries; i++){
System.out.print("Enter Name: ");
String nm = input.nextLine();
System.out.print("Enter Score: ");
int sc = input.nextInt();
input.nextLine();
s.entries[i] = new GameEntry(nm, sc);
System.out.println(s.toString());
}
}
}
This runs well like what it said in the book. It outputs:
//just an example input
[(John, 89), (Peter, 90), (Matthew, 90)]
What I don't understand is how did the names inside the parenthesis which is made in the GameEntry Class inside its toString() method (John, 89) is being outputted and yet what I written inside the System.out.println(s.toString); in Scores Class only pertains to the toString method in its own class?
I am expecting that the brackets in the toString() method in the Scores Class will be outputting only the brackets "[]" for it is the only one that I called in the main method... Can anyone please explain this to me how did this happened? I am little bit new in Java Data Structures.
Another thing I try to do this in a different sample program following the concept of what I see in the book..
This my codes:
//FirstClass
public class FirstClass
{
protected String name;
protected int age;
protected FirstClass(String n, int a) {
name = n;
age = a;
}
public String getName() { return name; }
public int getAge() { return age; }
public String printData() {
return "My name is: " + name + ", I am " + age + " years old";
}
}
//Second Class
import java.util.Scanner;
public class SecondClass
{
protected FirstClass f;
private static String nm;
private static int ag;
public SecondClass() {
f = new FirstClass(nm, ag);
}
public String toString(){
return "(" + f + ")";
}
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
SecondClass s = new SecondClass();
System.out.print("Enter Name: ");
nm = input.nextLine();
System.out.print("Enter Age: ");
ag = input.nextInt();
input.nextLine();
s.f = new FirstClass(nm, ag);
System.out.println(s.toString());
}
}
//Sample Input
Enter Name: John
Enter Age: 16
The output of this is:
(FirstClass#7cc7b1d2)
What I am expecting is:
("My name: is John, I am 16 years old")
What is my error in this???

How do you retrieve all of the records that a user inputs into an arraylist in java

I am trying to retrieve every record that an arraylist contains. I have a class called ContactList which is the super class of another class called BusinessContacts. My first task is to print only the first name and last name of a contact. The second task is to print details of a contact that's related to its id number. The ContactList class has all the instance variables and the set/get methods and the toString() method. The BusinessContact class consists of only two instance variables that need to be appended to the ContactList class. How is can this be worked out? The code is below:
The ContactList class:
package newcontactapp;
public abstract class ContactList {
private int iD;
private String firstName;
private String lastName;
private String adDress;
private String phoneNumber;
private String emailAddress;
// six-argument constructor
public ContactList(int id, String first, String last, String address, String phone, String email) {
iD = id;
firstName = first;
lastName = last;
adDress = address;
phoneNumber = phone;
emailAddress = email;
}
public ContactList(){
}
public void displayMessage()
{
System.out.println("Welcome to the Contact Application!");
System.out.println();
}
public void displayMessageType(String type)
{
System.out.println("This is a " + type);
System.out.println();
}
public int getiD() {
return iD;
}
public void setiD(int id) {
iD = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String first) {
firstName = first;
}
public String getLastName() {
return lastName;
}
public void setLastName(String last) {
lastName = last;
}
public String getAdDress() {
return adDress;
}
public void setAdDress(String address) {
adDress = address;
}
public String getPhoneNumber() {
return phoneNumber;
}
public void setPhoneNumber(String phone) {
phoneNumber = phone;
}
public String getEmailAddress() {
return emailAddress;
}
public void setEmailAddress(String email) {
emailAddress = email;
}
public String toString(){
return getiD() + " " + getFirstName() + " " + getLastName() + " " + getAdDress() + " " + getPhoneNumber() + " " + getEmailAddress() + "\n" ;
}
}
The BusinessContacts class:
package newcontactapp;
public class BusinessContacts extends ContactList {
private String jobTitle;
private String orGanization;
//
public BusinessContacts(int id, String first, String last, String address, String phone, String email, String job, String organization){
super();
jobTitle = job;
orGanization = organization;
}
public BusinessContacts(){
}
public String getJobTitle() {
return jobTitle;
}
public void setJobTitle(String job) {
jobTitle = job;
}
public String getOrGanization() {
return orGanization;
}
public void setOrGanization(String organization) {
orGanization = organization;
}
//#Override
public String toString(){
return super.toString()+ " " + getJobTitle()+ " " + getOrGanization() + "\n";
}
}
Here is my main method class:
package newcontactapp;
import java.util.ArrayList;
//import java.util.Iterator;
import java.util.Scanner;
public class NewContactAppTest {
//ArrayList<ContactList> fullList = new ArrayList<>();
ArrayList<ContactList> bContacts = new ArrayList<>();
ArrayList<ContactList> pContacts = new ArrayList<>();
public static void main(String [] args)
{
ContactList myContactList = new ContactList() {};
myContactList.displayMessage();
new NewContactAppTest().go();
}
public void go()
{
ContactList myContactList = new ContactList() {};
System.out.println("Menu for inputting a Business Contact or Personal Contact");
System.out.println();
Scanner input = new Scanner(System.in);
System.out.println("Please enter a numeric choice below: ");
System.out.println();
System.out.println("1. Add a Business Contact");
System.out.println("2. Add a Personal Contact");
System.out.println("3. Display Contacts");
System.out.println("4. Quit");
System.out.println();
String choice = input.nextLine();
if(choice.contains("1")){
String type1 = "Business Contact";
myContactList.displayMessageType(type1);
businessInputs();
}
else if(choice.contains("2")){
String type2 = "Personal Contact";
myContactList.displayMessageType(type2);
personalInputs();
}
else if(choice.contains("3")) {
displayContacts();
displayRecord();
}
else if(choice.contains("4")){
endOfProgram();
}
}
public void businessInputs()
{
BusinessContacts myBcontacts = new BusinessContacts();
//ContactList myContactList = new ContactList() {};
//ContactList nameContacts = new ContactList() {};
bContacts.clear();
int id = 0;
myBcontacts.setiD(id);
Scanner in = new Scanner(System.in);
while(true){
id = id + 1;
myBcontacts.setiD(id);
//myContactList.setiD(id);
System.out.println("Enter first name ");
String firstName = in.nextLine();
//nameContacts.setFirstName(firstName);
//myContactList.setFirstName(firstName);
myBcontacts.setFirstName(firstName);
System.out.println("Enter last name: ");
String lastName = in.nextLine();
//nameContacts.setLastName(lastName);
//myContactList.setLastName(lastName);
myBcontacts.setLastName(lastName);
System.out.println("Enter address: ");
String address = in.nextLine();
//myContactList.setAdDress(address);
myBcontacts.setAdDress(address);
System.out.println("Enter phone number: ");
String phoneNumber = in.nextLine();
//myContactList.setPhoneNumber(phoneNumber);
myBcontacts.setPhoneNumber(phoneNumber);
System.out.println("Enter email address: ");
String emailAddress = in.nextLine();
//myContactList.setEmailAddress(emailAddress);
myBcontacts.setEmailAddress(emailAddress);
System.out.println("Enter job title: ");
String jobTitle = in.nextLine();
myBcontacts.setJobTitle(jobTitle);
System.out.println("Enter organization: ");
String organization = in.nextLine();
myBcontacts.setOrGanization(organization);
//bContacts.add(myContactList);
bContacts.add(myBcontacts);
//names.add(nameContacts);
//System.out.println("as entered:\n" + bContacts);
System.out.println();
System.out.println("Enter another contact?");
Scanner input = new Scanner(System.in);
String choice = input.nextLine();
if(choice.equalsIgnoreCase("Y")) {
continue;
}
else{
break;
}
}
//bContacts.add(myBcontacts);
go();
}
public void personalInputs(){
ContactList myContactList = new ContactList() {};
PersonalContacts myPcontacts = new PersonalContacts();
Scanner in = new Scanner(System.in);
int id;
id = 1;
while(true){
System.out.println("Enter first name; ");
String firstName = in.nextLine();
myContactList.setFirstName(firstName);
myPcontacts.setFirstName(firstName);
System.out.println("Enter last name: ");
String lastName = in.nextLine();
myContactList.setLastName(lastName);
myPcontacts.setLastName(lastName);
System.out.println("Enter address: ");
String address = in.nextLine();
myContactList.setAdDress(address);
myPcontacts.setAdDress(address);
System.out.println("Enter phone number: ");
String phoneNumber = in.nextLine();
myContactList.setPhoneNumber(phoneNumber);
myPcontacts.setPhoneNumber(phoneNumber);
System.out.println("Enter email address: ");
String emailAddress = in.nextLine();
myContactList.setEmailAddress(emailAddress);
myPcontacts.setEmailAddress(emailAddress);
System.out.println("Enter birth date");
String dateOfBirth = in.nextLine();
myPcontacts.setDateOfBirth(dateOfBirth);
//pContacts.add(myContactList);
pContacts.add(myPcontacts);
id = id + 1;
myContactList.setiD(id);
System.out.println();
System.out.println("Enter another contact?");
Scanner input = new Scanner(System.in);
String choice = input.nextLine();
if (choice.equalsIgnoreCase("y")) {
continue;
}
else{
break;
}
}
go();
}
public void displayContacts(){
System.out.println();
for(ContactList name : bContacts){
System.out.println(name.getiD() + " " + name.getFirstName()+ " " + name.getLastName());
}
}
public void displayRecord(){
System.out.println();
System.out.println("Do you wish to see details of contact?");
Scanner input = new Scanner(System.in);
String choice = input.nextLine();
if(choice.equalsIgnoreCase("Y")) {
System.out.println();
System.out.println("Enter the numeric key from the list to see more specific details of that record");
System.out.println();
Scanner key = new Scanner(System.in);
System.out.println();
ContactList record = new ContactList() {};
for(int i = 0; i < bContacts.size(); i++){
record = bContacts.get(i);
System.out.println(record.toString());
}
}
else{
go();
}
/* else{
System.out.println();
System.out.println("This is a Personal Contact");
System.out.println();
for(int j = 0; j < pContacts.size(); j++){
ContactList pList = pContacts.get(j);
pList = pContacts.get(j);
System.out.println(pList.toString());
}
}*/
}
public void endOfProgram(){
System.out.println("Thank you! Have a great day!");
Runtime.getRuntime().exit(0);
}
}

If you're looking to get a value based on ID, try making a method that iterates over the contents of the ArrayList to find one that matches:
public ContactList getContactList(int id) {
for (ContactList list : /*your ContactList List object*/) {
if (list.getiD() == id) {
return list;
}
}
return null;
}
This will return null if none is found, or the first result in the list.