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How to access an object parameter from a hashmap value

I am trying to access the accOpBalance parameter from the Account method stored in the HashMap. I want to be able to change this value based on transaction type and store it again. I also want to save the the 6 most recent transactions fot the account but not sure how to approach the problem. I hope this describes the problem well enough. Im still very new to this and would love feedback on my code aswell.
public class BankingSystem{
static int accNum;
static String accName;
static String accAdd;
static String accOpDate;
static double accOpBalance;
int option = 0;
static Scanner keyboard = new Scanner(System.in);
static HashMap<Integer, Account> accounts = new HashMap<Integer, Account>(Map.of(
accNum, new Account(accNum, accName, accAdd, accOpDate, accOpBalance)
));
public BankingSystem() {
}
public static void main(String[] args) {
BankingSystem bankingSystem = new BankingSystem();
int option;
do{
option = mainMenu(keyboard);
System.out.println();
if(option == 1){
bankingSystem.createAccount(keyboard);
} else if (option == 2) {
bankingSystem.showAccounts();
} else if (option == 4) {
bankingSystem.deleteAccount();
}
}while(option != 5);
}
public void createAccount(Scanner keyboard) {
do{
System.out.println("-----------------------------------------------");
System.out.print("Please enter 1 to continue or -1 to exit: ");
option = keyboard.nextInt();
switch (option) {
case 1 -> {
Account newAccount = new Account(accNum, accName, accAdd, accOpDate, accOpBalance);
System.out.println("-----------------------------------------------");
System.out.print("Please enter the new account number: ");
accNum = keyboard.nextInt();
newAccount.setAccNum(accNum);
System.out.print("Please enter the name of the account holder: ");
accName = keyboard.next();
newAccount.setAccName(accName);
System.out.print("Please enter the address of the account holder: ");
accAdd = keyboard.next();
newAccount.setAccAdd(accAdd);
System.out.print("Please enter the accounts open date: ");
accOpDate = keyboard.next();
newAccount.setAccOpDate(accOpDate);
System.out.print("Please enter the starting balance: ");
accOpBalance = keyboard.nextDouble();
newAccount.setAccOpBalance(accOpBalance);
accounts.put(accNum, new Account(accNum, accName, accAdd, accOpDate, accOpBalance));
}
case 2 -> {
System.out.println("Please type -1 the exit create account menu: ");
option = keyboard.nextInt();
}
}
}while (option != -1);
}
public void showAccounts() {
for (Map.Entry<Integer, Account> accountEntry : accounts.entrySet()) {
System.out.println("Account key(number) = " + accountEntry.getKey() + accountEntry.getValue());
}
}
public void deleteAccount(){
int key;
option = 0;
do {
System.out.println("-----------------------------------------------");
System.out.print("Please enter 1 to continue or -1 to exit: ");
option = keyboard.nextInt();
switch (option) {
case 1 -> {
System.out.print("-----------------------------------------------");
System.out.print("Please enter the Account number of the" + "\n" +
" the account you wish to delete");
System.out.print("-----------------------------------------------");
key = keyboard.nextInt();
accounts.remove(key);
}
case 2 -> {
System.out.println("Please type -1 the exit delete account menu: ");
option = keyboard.nextInt();
}
}
}while (option != -1);
}
public static int mainMenu(Scanner keyboard){
int menuOption;
System.out.println("Welcome to the bank of Cal");
System.out.println("-----------------------------------------------");
System.out.println("Main Menu" + "\n" + "Please select option:");
System.out.println("1. Create Account");
System.out.println("2. Display Accounts");
System.out.println("3. Deposit/Withdraw");
System.out.println("4. Delete Account");
System.out.println("5. Exit Program");
System.out.println("-----------------------------------------------");
do{
menuOption = keyboard.nextInt();
}while(menuOption <1 || menuOption >5);
return menuOption;
}
public class Account {
private int accNum;
private String accName;
private String accAdd;
private String accOpDate;
private double accOpBalance;
Scanner getDetails = new Scanner(System.in);
public Account(int theAccNum, String theAccName, String theAccAdd, String theAccOpDate, double theAccOpBalance){
accNum = theAccNum;
accName = theAccName;
accAdd = theAccAdd;
accOpDate = theAccOpDate;
accOpBalance = theAccOpBalance;
}
public void setAccNum(int accNum){
this.accNum = accNum;
}
public int getAccNum(){
return accNum;
}
public void setAccName(String accName){
this.accName = accName;
}
public String getAccName(){
return accName;
}
public void setAccAdd(String accAdd){
this.accAdd = accAdd;
}
public String getAccAdd(){
return accAdd;
}
public void setAccOpDate(String accOpDate){
this.accOpDate = accOpDate;
}
public String getAccOpDate(){
return accOpDate;
}
public void setAccOpBalance(double accOpBalance){
this.accOpBalance = accOpBalance;
}
public double getAccOpBalance(){
return accOpBalance;
}
#Override
public String toString() {
return "\n" + "Account Number: " + accNum + "\n" + "Name: " + accName +
"\n" + "Account Holder Address: " + accAdd + "\n" +"Account open date: "
+ accOpDate + "\n" + "Account balance: " + accOpBalance;
}
}

cannot resolve or is not a field error

I am trying to search an arraylist of objects for an ID code, but I am stuck.
import java.util.Scanner;
import java.util.ArrayList;
public class Homework01{
public static void main(String[] args){
ArrayList<Transaction> argList = new ArrayList<Transaction>();
Scanner input = new Scanner(System.in);
System.out.println("Transaction List Menu");
System.out.println("=====================");
System.out.println("1) Add Transaction.");
System.out.println("2) Search Transactions.");
System.out.println("3) Filter.");
System.out.println("4) Display All Transactions.");
System.out.println("5) Exit.");
int menu = input.nextInt();
while (menu != 5) {
switch (menu) {
case 1:
addTransaction(argList);
break;
case 2:
;// Search Transaction
break;
case 3:
;// Filter Withdraws and Deposits
break;
case 4:
;// Display transactions
break;
case 5:
System.out.println("End");
break;
default:
System.out.println("Invalid response");
break;
}
menu = input.nextInt();
}
}
public static void addTransaction(ArrayList<Transaction> argList) {
Scanner input = new Scanner(System.in);
int tempId;
double tempAmount;
char tempType;
String tempDescription;
System.out.println("Enter in an ID for the transaction: ");
tempId = input.nextInt();
System.out.println("Enter in the amount of money: ");
tempAmount = input.nextDouble();
System.out.println("W for withdraw, D for deposit: ");
tempType = input.next(".").charAt(0);
System.out.println("Give transaction a description: ");
tempDescription = input.next();
//add transaction
argList.add(new Transaction(tempId, tempAmount, tempType, tempDescription) ); }
public static void searchTransactions(ArrayList<Transaction> argList){
Scanner input = new Scanner(System.in);
System.out.println("Please type in transaction ID: ");
int searchId = input.nextInt();
for(int i=0;i<argList.size();i++){
if(argList.argId.get(i).contains(searchId)){
System.out.println("Yes");
}
}
}
}
My second file contains this
public class Transaction {
int id;
char type;
double amount;
String description;
public Transaction(int argId, double argAmount,char argType, String
argDescription){
id = argId;
type = argType;
amount = argAmount;
description = argDescription;
}
public void getId(int id){
}
public void getAmount(double amount){
}
public void getType(char type){
}
public void getDescription(String description){
}
}
And i get the error message: argId cannot be resolved or is not a field on line 58. I think my error is that argId is not part of the ArrayList, and i need to find the right tern to search the ID codes in the ArrayList.
Thanks

Earlier, before you edited your question, you had wrong getter methods.
Instead of
public void getId(int id){
}
you should write this:
public int getId() {
return id;
}
Declare your fields in Transaction class as private.
Then change your other getters in the similar way.
About your actual question, you can use for-each loop:
public static void searchTransactions(ArrayList<Transaction> argList) {
try (Scanner input = new Scanner(System.in)) {
System.out.println("Please type in transaction ID: ");
int searchId = input.nextInt();
for (Transaction transaction : argList) {
if (transaction.getId() == searchId) {
System.out.println("Yes");
break;
}
}
}
}
If you insist for i loop, change it this way:
for (int i = 0; i < argList.size(); i++) {
if(argList.get(i).getId() == searchId){
System.out.println("Yes");
break;
}
}

ArgId is a property of the objects in the list, not a property of the list itself which is why the compiler is giving you an error.

Looks like a typo:
You have:
argList.argId.get(i).contains(searchId)
try using:
argList.get(i).argId.contains(searchId)
argList is a collection, then you get object, read argId and check if it contains searchId
I would suggest to encapsulate class Transaction:
public class Transaction {
private int id;
private char type;
private double amount;
private String description;
public Transaction(int argId, double argAmount, char argType, String argDescription) {
id = argId;
type = argType;
amount = argAmount;
description = argDescription;
}
public int getId() {
return id;
}
public char getType() {
return type;
}
public double getAmount() {
return amount;
}
public String getDescription() {
return description;
}
}
Then main class will look in this way:
import java.util.Scanner;
import java.util.ArrayList;
public class Homework01{
public static void main(String[] args){
ArrayList<Transaction> argList = new ArrayList<Transaction>();
Scanner input = new Scanner(System.in);
System.out.println("Transaction List Menu");
System.out.println("=====================");
System.out.println("1) Add Transaction.");
System.out.println("2) Search Transactions.");
System.out.println("3) Filter.");
System.out.println("4) Display All Transactions.");
System.out.println("5) Exit.");
int menu = input.nextInt();
while (menu != 5) {
switch (menu) {
case 1: ; addTransaction(argList);
break;
case 2: ;// Search Transaction
break;
case 3: ;// Filter Withdraws and Deposits
break;
case 4: ;// Display transactions
break;
case 5: System.out.println("End");
break;
default: System.out.println("Invalid response");
break;
}
menu = input.nextInt();
}
}
public static void addTransaction(ArrayList<Transaction> argList) {
Scanner input = new Scanner(System.in);
int tempId;
double tempAmount;
char tempType;
String tempDescription;
System.out.println("Enter in an ID for the transaction: ");
tempId = input.nextInt();
System.out.println("Enter in the amount of money: ");
tempAmount = input.nextDouble();
System.out.println("W for withdraw, D for deposit: ");
tempType = input.next(".").charAt(0);
System.out.println("Give transaction a description: ");
tempDescription = input.next();
//add transaction
argList.add(new Transaction(tempId, tempAmount, tempType, tempDescription)
);
}
public static void searchTransactions(ArrayList<Transaction> argList){
Scanner input = new Scanner(System.in);
System.out.println("Please type in transaction ID: ");
int searchId = input.nextInt();
for(int i=0;i<argList.size();i++){
if(argList.get(i).getId()==searchId){
System.out.println("Yes");
}
}
}
}

Using Linked List as the output?

I'm trying to write a bank account that asks the user if they want to see records, remove records, and other stuff. This is what I'm trying to produce
My program is nearly done the only problem I'm having is getting the output. I'm getting some weird error when i tried producing the output. When the output works. I'll put it inside a linked list.
public class Bank
{
public static void main(String args[]){
ArrayList<Customer> accounts = new ArrayList<Customer>();
Customer customer1 = new Customer(1, "Savings", "Dollars", 800);
Customer customer2 = new Customer(2, "Checking", "Euro", 1900);
Customer customer3 = new Customer(3, "Checking", "Pound", 8000);
accounts.add(customer1);
accounts.add(customer2);
accounts.add(customer3);
int customerID=4;
String choice;
int deposit;
int withdraw;
Scanner in = new Scanner(System.in);
Customer operation = new Customer();
boolean flag = true;
String accountType;
String currencyType;
int balance;
while(flag){
System.out.println("Select a choice:");
System.out.println("1. Existing customer");
System.out.println("2. New customer");
System.out.println("3. Quit");
String input = in.next();
//existing user
if(input.equals("1")){
System.out.println("Enter CustomerID: ");
customerID = in.nextInt();
System.out.println("Would you like to: ");
System.out.println("1. Deposit ");
System.out.println("2. Withdraw ");
System.out.println("3. Display account info ");
System.out.println("4. Check balance ");
choice = in.next();
if(choice.equals("1")){
System.out.println("How much would you like to deposit?");
deposit = in.nextInt();
operation.deposit(deposit);
}
else if (choice.equals("2")){
System.out.println("How much would you like to withdraw?");
withdraw = in.nextInt();
operation.withdraw(withdraw);
}
else if (choice.equals("3")){
operation.display(accounts.get(customerID));
}
else if (choice.equals("4"))
operation.balance(accounts.get(customerID));
else
System.out.println("Invalid");
}
//new user
else if(input.equals("2")){
//add new user to arraylist
int newID = customerID + 1;
System.out.println("Enter account type: ");
accountType = in.next();
System.out.println("Enter currency type: ");
currencyType = in.next();
System.out.println("Enter initial balance: ");
balance = in.nextInt();
System.out.println("Your customer ID will be: " + newID);
accounts.add(new Customer(newID, accountType, currencyType, balance));
}
else if(input.equals("3")){
System.out.println("Thanks for using this bank!");
flag = false;
}
else{
System.out.println("Invalid");
}
}
}
}
My second class:
public class Customer
{
String accountType, currencyType, info;
public int customerID, balance, amount;
Scanner input = new Scanner(System.in);
public Customer(int customerID, String accountType, String currencyType, int balance)
{
this.accountType = accountType;
this.currencyType = currencyType;
this.customerID = customerID;
this.balance = balance;
this.amount = amount;
}
public Customer() {
// TODO Auto-generated constructor stub
}
public int deposit(int amount){
amount = input.nextInt();
if (amount >= 500) {
System.out.println("Invalid");
}
else{
balance = balance + amount;
}
return balance;
}
public int withdraw(int amount){
if (balance < amount) {
System.out.println("Invalid amount.");
}
else if (amount >= 500) {
System.out.println("Invalid");
}
else {
balance = balance - amount;
}
return balance;
}
public void display(ArrayList<Customer> accounts)
{
System.out.println("CustomerID:" + accounts.customerID);
System.out.println("Account Type:" + accounts.accountType);
System.out.println("Currency Type: " + accounts.currencyType);
System.out.println("Balance:" + accounts.balance);
}
public void balance(ArrayList<Customer> accounts) {
System.out.println("Balance:" + accounts.balance);
}
}

java.util.ArrayList won't have properties or methods such as customerID, accountType, currencyType and balance.
I guess your methods display() and balance() shoudn't take any arguments and should use the properties of the instance to print.
public void display()
{
System.out.println("CustomerID:" + customerID);
System.out.println("Account Type:" + accountType);
System.out.println("Currency Type: " + currencyType);
System.out.println("Balance:" + balance);
}
public void balance() {
System.out.println("Balance:" + balance);
}
Then, these lines
operation.display(accounts.get(customerID));
operation.balance(accounts.get(customerID));
should be
accounts.get(customerID).display();
accounts.get(customerID).balance();
There seems many more things to be corrected -- for example, usage of withdraw().

How to connect multiple ArrayLists in different classes. (Bank program in java)

I'm involved in a group assignment where we are supposed to create a bank program. This is our first time programming in java. We are stuck and we are having trouble figuring out how to connect our customer and account classes. They both consist of ArrayLists and we want the customer arraylists to contain the accounts. So that if we delete a customer, the accounts that belong to that customer will also be deleted. Can anyone give us a push in the right direction?
This is our main class which contains the bank menu:
package bank6;
import java.util.Scanner;
import java.util.HashMap;
import java.util.Map;
public class Bankmenu {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
Customer client = new Customer();
Account bank = new Account();
Account accs = new Account();
Customer cust1, cust2, cust3;
cust1 = new Customer("8905060000", "Henrik");
cust2 = new Customer("8910210000", "Emelie");
cust3 = new Customer("8611040000", "Fredrik");
bank.addNewAccount(cust1);
bank.addNewAccount(cust2);
bank.addNewAccount(cust3);
client.addCustomerAr(cust1);
client.addCustomerAr(cust2);
client.addCustomerAr(cust3);
int ChoiceOne = 0;
int CustChoice;
int currentCustomer;
int currentAccount;
int amountC;
int amountD;
int editCust;
String personNummer = null;
String Pnr = "0";
int AdminChoice;
/*prompts the user to set ChoiceOne equal to 1 or 2. Hasnextint checks
if the input is an int. else asks for new input. */
while (ChoiceOne != 1 && ChoiceOne != 2) {
System.out.println("Press 1 to login as customer or 2 to login as admin ");
if (input.hasNextInt()) {
ChoiceOne = input.nextInt();
System.out.println();
} else {
System.out.println("You must enter number 1 or number 2");
input.next();
}//ends else
}//ends while
/*
If the user chooses 1 in the previous question, the user will be sent to
the interface for the customer. User is then asked to enter his social
security number and this number will be checked using the Luhn algoritm. Since
the scanner input is already used we added a new Scanner calleds nexLine
to deal with custPnr as a string.
(http://stackoverflow.com/questions/5032356/using-scanner-nextline)
*/
if (ChoiceOne == 1) {
//boolean quit=false;
while ("0".equals(Pnr)) {
// System.out.println("Welcome customer. Please login by using your birthdate (yymmddnnnn) ");
// Scanner nextLine = new Scanner(System.in);
// Pnr = nextLine.nextLine();
//Luhn.checkLogin(Pnr);
//Här måste en kontroll med Luhn algoritmen göras.
// getUserBirthdate();
boolean CorrectBirthDate = false;
while (CorrectBirthDate == false) {
System.out.println("Please enter your birthdate");
Scanner inception = new Scanner(System.in);
personNummer = inception.next();
CorrectBirthDate = Luhn.checkLogin(personNummer);
if (CorrectBirthDate == false) {
System.out.println("Incorrect birthdate. You will be prompted to type it again");
}
}
break;
/* }
Sets "quit" to false and executes quit=true if customer chooses case 0
*/
}
boolean quit = false;
do {
// boolean quit = false;
//System.out.println();
System.out.println("Logged on as " + personNummer);
System.out.println("1. deposit money");
System.out.println("2. Withdraw money");
System.out.println("3. Check balance");
System.out.print("Your choice, 0 to quit: ");
CustChoice = input.nextInt();
switch (CustChoice) {
case 1: //Deposit money
System.out.println(bank.getAccountNumbersFor(personNummer));
System.out.println("Enter account number:");
currentAccount = input.nextInt();
System.out.println("Enter amount to deposit:");
amountC = input.nextInt();
System.out.println(bank.creditAccount(currentAccount, amountC));
System.out.println(bank.getAccountNumbersFor("Henrik"));
break;
case 2://Withdraw money
// System.out.println(bank.getAccNosFor(custPnr));
bank.getAccountNo();
System.out.println("Enter account number:");
currentAccount = input.nextInt();
System.out.println("Enter amount to withdraw:");
amountD = input.nextInt();
System.out.println(bank.debitAccount(currentAccount, amountD));
System.out.println(bank.getAccountNumbersFor("Henrik"));
break;
case 3://Check ballance and accounts
System.out.println(bank.getAccountNumbersFor("Henrik"));
break;
case 0:
quit = true;
break;
default:
System.out.println("Wrong choice.");
break;
}
System.out.println();
} while (!quit);
System.out.println("Bye!");
}//ends if
else if (ChoiceOne == 2) {
while ("0".equals(Pnr)) {
boolean CorrectBirthDate = false;
while (CorrectBirthDate == false) {
System.out.println("Please enter your birthdate");
Scanner inception = new Scanner(System.in);
personNummer = inception.next();
CorrectBirthDate = Luhn.checkLogin(personNummer);
if (CorrectBirthDate == false) {
System.out.println("Incorrect birthdate. You will be prompted to type it again");
}
}
break;
}
//AdminpNr = input.nextInt();
//Här måste en kontroll av AdminpNr göras med hjälp av Luhn.
boolean quit = false;
do {
System.out.println("1. Add customer");
System.out.println("2. Add account");
System.out.println("3. List customer");
System.out.println("4. List accounts");
System.out.println("5. Remove customer");
System.out.println("6. Remove account");
System.out.print("Your choice, 0 to quit: ");
AdminChoice = input.nextInt();
switch (AdminChoice) {
case 1://add customer
int i = 0;
do {
System.out.println("Skriv in nytt personnummer:");
Scanner scan = new Scanner(System.in);
Map<String, Customer> testCustomers = new HashMap<String, Customer>();
String name = scan.nextLine();
//System.out.println("Att arbeta på bank ska vara jobbigt, skriv in det igen:");
//String pnummer = scan.nextLine();
String pnummer = name;
System.out.println("Skriv in namn:");
String kundnamn = scan.nextLine();
Customer obj = new Customer(pnummer, kundnamn);
testCustomers.put(name, obj);
client.addCustomerAr(obj);
i++;
} while (i < 2);
break;
case 2://add account
int i2 = 0;
do {
System.out.println("Skriv in nytt personnummer:");
Scanner scan = new Scanner(System.in);
Map<Long, Account> testAccs = new HashMap<Long, Account>();
Long name = scan.nextLong();
//System.out.println("Skriv in personnummer igen:");
Long own = name;
long bal = 0;
Account obt = new Account(own, bal);
testAccs.put(name, obt);
accs.addAccAr(obt);
i2++;
} while (i2 < 2);
break;
case 3:// List customer and accounts
for (String info : client.getAllClients()) {
System.out.println(info);
}
break;
case 4:
for (Long infoAcc : accs.getAllAccounts()) {
System.out.println(infoAcc);
}
break;
case 5:
// ta bort kund
break;
case 6:
// ta bort konto
break;
case 0:
quit = true;
break;
default:
System.out.println("Wrong choice.");
break;
}
System.out.println();
} while (!quit);
System.out.println("Bye!");
}//ends else if
}//ends main
/* private static void getUserBirthdate() {
boolean CorrectBirthDate = false;
while (CorrectBirthDate == false) {
System.out.println("Please enter your birthdate");
Scanner inception = new Scanner (System.in);
String personNummer = inception.next();
CorrectBirthDate = Luhn.checkLogin(personNummer);
if (CorrectBirthDate == false) {
System.out.println("Incorrect birthdate. You will be prompted to type it again");
}
}
}
*/
}//ends class
This is our Account class;
package bank6;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.ListIterator;
public class Account {
private ArrayList accounts;
private Object lastAcc;
public String customerSocial;
private Integer balance;
private Integer accountNumber;
private Customer owner;
private Account Customer6; // Association customer/account.
private ArrayList<Account> myAccounts = new ArrayList<Account>();
public Integer deposit;
public Integer withdraw;
static Integer accountNo = 1010;
private Long persnr;
private long balans = 0;
/*Constructor.. A account cannot exist unless it is owned by a customer*/
public Account(Customer owner, Integer balance) {
this.owner = owner;
this.balance = balance;
accountNumber = accountNo++;
}
public Account() {
accounts = new ArrayList();
}
public Account(Long persnr, long balans) {
this.persnr = persnr;
this.balans = balans;
accountNumber = accountNo++;
}
public Integer getAccountNo() {
return accountNumber;
}
public String getOwner() {
return owner.getName();
}
public Customer getOwn() {
return owner;
}
public Integer getBalance() {
return balance;
}
//credits the account with an amount of money and returns a string
public String credit(Integer anAmount) {
balance += anAmount;
// return "Account number " + accountNumber + " Has been credited with "+anAmount + " kr.";
return " " + anAmount + " kr has been deposited to " + accountNumber + "\n";
}
public boolean canDebit(Integer anAmount) {
return anAmount <= balance;
}
public String debit(Integer anAmount) {
if (this.canDebit(anAmount)) {
balance -= anAmount;
return " " + anAmount + " kr has been withdrawn from " + accountNumber + "\n";
} else {
return "Account number" + accountNo + "has insufficient funds to debit"
+ anAmount;
}
}
public void addNewAccount(Customer customer) {
accounts.add(new Account(customer, 0));
lastAcc = accounts.get(accounts.size() - 1);
System.out.println("*** New account created. ***" //+ lastAcc
+ "\n");
}
public String removeAccount(int accountNumber) {
boolean found = false;
String results = "";
ListIterator iter = accounts.listIterator();
while (iter.hasNext() && found) {
Account account = (Account) iter.next();
if (account.getAccountNo() == accountNumber) {
found = true; //there is a match stop the loop
if (account.getBalance() == 0) {
iter.remove();//remove this account object
results = "Account number " + accountNumber + " has been removed";
} else {
results = "Account number " + accountNumber + " cannot be removed"
+ "as it has a balance of: " + account.getBalance();
}
}//ends if there is a match
}// end while loop
if (!found) {
results = "No such account";
}
return results;
}
public String creditAccount(int accountNumber, Integer anAmount) {
boolean found = false;
String results = "";
ListIterator iter = accounts.listIterator();
while (iter.hasNext() && !found) {
Account account = (Account) iter.next();
if (account.getAccountNo() == accountNumber) {
results = account.credit(anAmount);
found = true;//stop the loop
}
}
if (!found) {
results = "No such customer";
}
return results;
}
public String debitAccount(int accountNumber, Integer anAmount) {
boolean found = false;
String results = "";
ListIterator iter = accounts.listIterator();
while (iter.hasNext() && !found) {
Account account = (Account) iter.next();
if (account.getAccountNo() == accountNumber) {
results = account.debit(anAmount);
found = true;
}
}
if (!found) {
results = "No such Customer";
}
return results;
}
public String getAccountNumbersFor(String CustomerName) {
String details = CustomerName + " has the followinng accounts: "
+ "\n\n";
Iterator iter = accounts.iterator();
//visit all of the accounts in the ArrayList
while (iter.hasNext()) {
Account account = (Account) iter.next();
if (account.getOwner().equals(CustomerName)) {
details += " Account number " + account.getAccountNo()
+ " Balance " + account.getBalance() + "kr \n";
}//ends if
}//ends while
return details;
}
public String bankAccounts() {
String details = "ALL BANK ACCOUNTS" + "\n"
+ "-----------------" + '\n';
if (accounts.size() == 0) {
details += "There are no bank accounts";
} else {
Iterator iter = accounts.iterator();
while (iter.hasNext()) {
details += iter.next().toString() + '\n';
}
}
return details;
}
#Override
public String toString() {
return "Account " + accountNumber + ": " + owner
+ "\nBalance: " + balance + " kr.\n";
}
public Boolean authenticateUser(String login, String ssn) {
if (Luhn.checkLogin(ssn)) {
System.out.println("User authenticated");
return true;
} else {
System.out.println("Authentication refused");
return false;
}
}
public void addAccAr(Account myAccount) {
myAccounts.add(myAccount);
}
public Long getBalanceToLong() {
long balTemp = balans;
return balTemp;
}
public Long getPnTorLong() {
return persnr;
}
public Long getAccNoLong() {
long accTemp = accountNumber;
return accTemp;
}
public ArrayList<Long> getAllAccounts() {
ArrayList<Long> allAccounts = new ArrayList<>();
System.out.println("ALL ACCOUNTS\n-----------");
for (Account myAccount : myAccounts) {
allAccounts.add(myAccount.getAccNoLong());
allAccounts.add(myAccount.getPnTorLong());
allAccounts.add(myAccount.getBalanceToLong());
}
return allAccounts;
}
/*
public ArrayList<String> getMyAccounts() {
ArrayList<String> ownAccounts = new ArrayList<>();
System.out.println("MY ACCOUNTS\n-----------");
for (Account myAccount : myAccounts) {
ownAccounts.add(myAccount.getAccNoStr());
ownAccounts.add(myAccount.getBalanceToStr());
}
return ownAccounts;
}*/
}
This is our Customer class
package bank6;
import java.util.ArrayList;
public class Customer {
int custCounter;
//attribut
private Long socialNo;
private String name;
private ArrayList customers;
public Integer customerNumber;
static Integer custNo = 1;
private ArrayList<Customer> clients = new ArrayList<Customer>();
//konstruktor
public Customer(String socialStr, String name) {
Long socialTemp = new Long(socialStr);
this.name = name;
this.socialNo = socialTemp;
customerNumber = custNo++;
}//ends konstruktor customer6
public Customer() {
customers = new ArrayList();
}
/* Set methods*/
public void setName(String name) {
this.name = name;
}
public void setsocialNo(Long socialNo) {
this.socialNo = socialNo;
}
/* get methods */
public String getName() {
return name;
}
public String getSocialNoStr() {
String socialTemp = Long.toString(socialNo);
return socialTemp;
}
public Long getSocialNo() {
return socialNo;
}
/*toString() method*/
#Override
public String toString() {
return "\n" + "Owner: " + name + " (" + socialNo + ")";
}
public void addAccCustAr() {
}
public void addCustomerAr(Customer client) {
clients.add(client);
}
public ArrayList<String> getAllClients() {
ArrayList<String> allClients = new ArrayList<>();
System.out.println("ALL CLIENTS\n-----------");
for (Customer client : clients) {
allClients.add(client.getName());
allClients.add(client.getSocialNoStr() + "\n");
}
return allClients;
//add account
//public void addAccount(account6 account){
// accounts.add(account);
//}// ends adds account
//remove account
//public void removeAccount (account6 account) {
// accounts.remove(account);
//}//ends remove account
}
}//ends public class
This is our Luhn class
package bank6;
public class Luhn {
public static boolean checkLogin(String pnr) {
if (pnr.length() != 10) {
System.out.println("");
return false;
} else {
int length = pnr.length();
int sum = 0;
int pos = length - 1;
for (int i = 1; i <= length; i++, pos--) {
char tmp = pnr.charAt(pos);
int num = Integer.parseInt(String.valueOf(tmp));
int produkt;
if (i % 2 != 0) {
produkt = num * 1;
} else {
produkt = num * 2;
}
if (produkt > 9) {
produkt -= 9;
}
sum += produkt;
}
boolean korrekt = (sum % 10) == 0;
if (korrekt) {
System.out.println("Correct");
return true;
} else {
System.out.println("Invalid");
return false;
}
}
}
}

Your Account class already has a Customer field -- good.
You should give Customer an ArrayList<Account> accounts field.
And also give Customer addAccount(Account acct) and removeAccount(Account acct) methods.
Why does Customer have an ArrayList<Customer> field? That makes little sense. Should a Customer hold a list of other Customers? Why? For what purpose?
Why does Account have private ArrayList<Account> myAccounts = new ArrayList<Account>();? That also makes little sense. Should an Account hold a bunch of other Accounts? Again, for what purpose?
The Account class should logically represent one and only one Account.
Same for the Customer class -- it should logically represent only one Customer.
If you think through things logically, they usually come together, and each component of your code should make sense. If it doesn't, question why it is there.
So this code is broken:
Account bank = new Account();
//....
bank.addNewAccount(cust1);
bank.addNewAccount(cust2);
bank.addNewAccount(cust3);
Since you're adding a bunch of Customer's to an Account object. It looks like you should have another class, a Bank class, one that can hold an ArrayList<Customer>. Wouldn't this make sense?

Creating a Bank program [closed]

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Closed 9 years ago.
I am almost done with an assignment. I am creating a Bank program, and I have almost everything done. The part that I am stuck on is the transactions part. I have to create a function public String getTransactionInfo(int n) which returns the last n transactions of a bank account. I cannot seem to figure this part out. i have a variable private int numOfTransactions and I tried incorporating that into the function, but it didn't work. this is what I tried.
public String gettransactionInfo(int n)
{
numOfTransactions = n;
return n;
}
that did not work. cannot figure out how to return this is a string. any ideas?
import java.util.Scanner;
public class BankApp {
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
Bank myBank = new Bank();
int user_choice = 2;
do {
//display menu to user
//ask user for his choice and validate it (make sure it is between 1 and 6)
System.out.println();
System.out.println("1) Open a new bank account");
System.out.println("2) Deposit to a bank account");
System.out.println("3) Withdraw to bank account");
System.out.println("4) Print short account information");
System.out.println("5) Print the detailed account information including last transactions");
System.out.println("6) Quit");
System.out.println();
System.out.print("Enter choice [1-6]: ");
user_choice = s.nextInt();
switch (user_choice) {
case 1: System.out.println("Enter a customer name");
String cn = s.next();
System.out.println("Enter a opening balance");
double d = s.nextDouble();
System.out.println("Account was created and it has the following number: " + myBank.openNewAccount(cn, d));
break;
case 2: System.out.println("Enter a account number");
int an = s.nextInt();
System.out.println("Enter a deposit amount");
double da = s.nextDouble();
myBank.depositTo(an, da);
break;
case 3: System.out.println("Enter a account number");
int acn = s.nextInt();
System.out.println("Enter a withdraw amount");
double wa = s.nextDouble();
myBank.withdrawFrom(acn, wa);
break;
case 4: System.out.println("Enter a account number");
int anum = s.nextInt();
myBank.printAccountInfo(anum);
break;
//case 5: ... break;
}
}
while (user_choice != '6');
}
static class Bank {
private BankAccount[] accounts; // all the bank accounts at this bank
private int numOfAccounts; // the number of bank accounts at this bank
// Constructor: A new Bank object initially doesn’t contain any accounts.
public Bank() {
accounts = new BankAccount[100];
numOfAccounts = 0;
}
// Creates a new bank account using the customer name and the opening balance given as parameters
// and returns the account number of this new account. It also adds this account into the account list
// of the Bank calling object.
public int openNewAccount(String customerName, double openingBalance) {
BankAccount b = new BankAccount(customerName, openingBalance);
accounts[numOfAccounts] = b;
numOfAccounts++;
return b.getAccountNum();
}
// Withdraws the given amount from the account whose account number is given. If the account is
// not available at the bank, it should print a message.
public void withdrawFrom(int accountNum, double amount) {
for (int i =0; i<numOfAccounts; i++) {
if (accountNum == accounts[i].getAccountNum() ) {
accounts[i].withdraw(amount);
System.out.println("Amount withdrawn successfully");
return;
}
}
System.out.println("Account number not found.");
}
// Deposits the given amount to the account whose account number is given. If the account is not
// available at the bank, it should print a message.
public void depositTo(int accountNum, double amount) {
for (int i =0; i<numOfAccounts; i++) {
if (accountNum == accounts[i].getAccountNum() ) {
accounts[i].deposit(amount);
System.out.println("Amount deposited successfully");
return;
}
}
System.out.println("Account number not found.");
}
// Prints the account number, the customer name and the balance of the bank account whose
// account number is given. If the account is not available at the bank, it should print a message.
public void printAccountInfo(int accountNum) {
for (int i =0; i<numOfAccounts; i++) {
if (accountNum == accounts[i].getAccountNum() ) {
System.out.println(accounts[i].getAccountInfo());
return;
}
}
System.out.println("Account number not found.");
}
// Prints the account number, the customer number and the balance of the bank account whose
// account number is given, together with last n transactions on that account. If the account is not
// available at the bank, it should print a message.
public void printAccountInfo(int accountNum, int n) {
for (int i =0; i<numOfAccounts; i++) {
if (accountNum == accounts[i].getAccountNum() ) {
System.out.println(accounts[i].getAccountInfo());
System.out.println(accounts[i].getTransactionInfo(n));
return;
}
}
System.out.println("Account number not found.");
}
}
static class BankAccount{
private int accountNum;
private String customerName;
private double balance;
private double[] transactions;
private int numOfTransactions;
private static int noOfAccounts=0;
public String getAccountInfo(){
return "Account number: " + accountNum + "\nCustomer Name: " + customerName + "\nBalance:" + balance +"\n";
}
public String getTransactionInfo(int n)
{
numOfTransactions = n;
return n;
}
public BankAccount(String abc, double xyz){
customerName = abc;
balance = xyz;
noOfAccounts ++;
accountNum = noOfAccounts;
transactions = new double[100];
transactions[0] = balance;
numOfTransactions = 1;
}
public int getAccountNum(){
return accountNum;
}
public void deposit(double amount){
if (amount<=0) {
System.out.println("Amount to be deposited should be positive");
} else {
balance = balance + amount;
transactions[numOfTransactions] = amount;
numOfTransactions++;
}
}
public void withdraw(double amount)
{
if (amount<=0){
System.out.println("Amount to be withdrawn should be positive");
}
else
{
if (balance < amount) {
System.out.println("Insufficient balance");
} else {
balance = balance - amount;
transactions[numOfTransactions] = amount;
numOfTransactions++;
}
}
}
}//end of class
}

I think the correct solution to your problem will be something like this:
public String gettransactionInfo(int n)
{
//Traverse the "transactions" array in *reverse* order
//In For loop start with transactions.length, and decrement by 1 "n" times
// Append the transaction amount to a String
// Return the string.
}

public String gettransactionInfo(int n)
{
numOfTransactions = n;
return n;
}
Hehe! What are you exactly trying to do here? :) ... You messed up the rvalue and lvalue, but that's not related to the answer.
The key is to have a String Array in the class. Every time a transaction happens append the transaction details to the array..... Then gettransactionInfo should print the last n details in the string...
e.g.
transInfo[0] = "A deposited 30K"
transInfo[1] = "B withdrew 20K"
transInfo[2] = "C deposited 5k"
Last 1 transaction displays the last entry in the string "C deposited 5k"

If you want to return the number of transactions as a String, as opposed to the integer (which you have it stored as), then you want to convert the integer to a String.
In Java, you would do so via:
Integer.toString(numOfTransactions)
Side note: Out of curiosity, in your program, why are you doing this?
public String gettransactionInfo(int n)
{
numOfTransactions = n;
return n;
}
That is inefficient and wrong since you are setting the numberOfTransactions to the n value. That functionality, by convention is put in a setter method, as opposed to a getter method - which is what your implementation is supposed to do.
Ideally, it should be:
public String gettransactionInfo()
{
return Integer.toString(numOfTransactions);
}
EDIT:
As per the comments, the correct thing to do would be to return an index from the transactions array, corresponding to index n.
Where, in this case the transactions array should be a String array.
EDIT 2:
In the case where you use a separate string array, you would update it (depending on the transaction) as follows:
import java.util.Scanner;
public class BankApp {
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
Bank myBank = new Bank();
int user_choice = 2;
do {
//display menu to user
//ask user for his choice and validate it (make sure it is between 1 and 6)
System.out.println();
System.out.println("1) Open a new bank account");
System.out.println("2) Deposit to a bank account");
System.out.println("3) Withdraw to bank account");
System.out.println("4) Print short account information");
System.out.println("5) Print the detailed account information including last transactions");
System.out.println("6) Quit");
System.out.println();
System.out.print("Enter choice [1-6]: ");
user_choice = s.nextInt();
switch (user_choice) {
case 1: System.out.println("Enter a customer name");
String cn = s.next();
System.out.println("Enter a opening balance");
double d = s.nextDouble();
System.out.println("Account was created and it has the following number: " + myBank.openNewAccount(cn, d));
break;
case 2: System.out.println("Enter a account number");
int an = s.nextInt();
System.out.println("Enter a deposit amount");
double da = s.nextDouble();
myBank.depositTo(an, da);
break;
case 3: System.out.println("Enter a account number");
int acn = s.nextInt();
System.out.println("Enter a withdraw amount");
double wa = s.nextDouble();
myBank.withdrawFrom(acn, wa);
break;
case 4: System.out.println("Enter a account number");
int anum = s.nextInt();
myBank.printAccountInfo(anum);
break;
case 5: System.out.println("Enter a account number");
anum = s.nextInt();
myBank.printTransactionInfo(anum);
break;
default: System.out.println("Invalid option. Please try again.");
}
}
while (user_choice != '6');
}
static class Bank {
private BankAccount[] accounts; // all the bank accounts at this bank
private int numOfAccounts; // the number of bank accounts at this bank
//Constructor: A new Bank object initially doesn’t contain any accounts.
public Bank() {
accounts = new BankAccount[100];
numOfAccounts = 0;
}
// Creates a new bank account using the customer name and the opening balance given as parameters
// and returns the account number of this new account. It also adds this account into the account list
// of the Bank calling object.
public int openNewAccount(String customerName, double openingBalance) {
BankAccount b = new BankAccount(customerName, openingBalance);
accounts[numOfAccounts] = b;
numOfAccounts++;
return b.getAccountNum();
}
// Withdraws the given amount from the account whose account number is given. If the account is
// not available at the bank, it should print a message.
public void withdrawFrom(int accountNum, double amount) {
for (int i =0; i<numOfAccounts; i++) {
if (accountNum == accounts[i].getAccountNum() ) {
accounts[i].withdraw(amount);
System.out.println("Amount withdrawn successfully");
return;
}
}
System.out.println("Account number not found.");
}
// Deposits the given amount to the account whose account number is given. If the account is not
// available at the bank, it should print a message.
public void depositTo(int accountNum, double amount) {
for (int i =0; i<numOfAccounts; i++) {
if (accountNum == accounts[i].getAccountNum() ) {
accounts[i].deposit(amount);
System.out.println("Amount deposited successfully");
return;
}
}
System.out.println("Account number not found.");
}
// Prints the account number, the customer name and the balance of the bank account whose
// account number is given. If the account is not available at the bank, it should print a message.
public void printAccountInfo(int accountNum) {
for (int i =0; i<numOfAccounts; i++) {
if (accountNum == accounts[i].getAccountNum() ) {
System.out.println(accounts[i].getAccountInfo());
return;
}
}
System.out.println("Account number not found.");
}
public void printTransactionInfo(int accountNum) {
for (int i =0; i<numOfAccounts; i++) {
if (accountNum == accounts[i].getAccountNum() ) {
System.out.println(accounts[i].getAccountInfo());
System.out.println("Last transaction: " + accounts[i].getTransactionInfo(accounts[i].getNumberOfTransactions()-1));
return;
}
}
System.out.println("Account number not found.");
}
// Prints the account number, the customer number and the balance of the bank account whose
// account number is given, together with last n transactions on that account. If the account is not
// available at the bank, it should print a message.
public void printAccountInfo(int accountNum, int n) {
for (int i =0; i<numOfAccounts; i++) {
if (accountNum == accounts[i].getAccountNum() ) {
System.out.println(accounts[i].getAccountInfo());
System.out.println(accounts[i].getTransactionInfo(n));
return;
}
}
System.out.println("Account number not found.");
}
}
static class BankAccount{
private int accountNum;
private String customerName;
private double balance;
private double[] transactions;
private String[] transactionsSummary;
private int numOfTransactions;
private static int noOfAccounts=0;
public String getAccountInfo(){
return "Account number: " + accountNum + "\nCustomer Name: " + customerName + "\nBalance:" + balance +"\n";
}
public String getTransactionInfo(int n)
{
String transaction = transactionsSummary[n];
if (transaction == null) {
return "No transaction exists with that number.";
}
else {
return transaction;
}
}
public BankAccount(String abc, double xyz){
customerName = abc;
balance = xyz;
noOfAccounts ++;
accountNum = noOfAccounts;
transactions = new double[100];
transactionsSummary = new String[100];
transactions[0] = balance;
transactionsSummary[0] = "A balance of : $" + Double.toString(balance) + " was deposited.";
numOfTransactions = 1;
}
public int getAccountNum(){
return accountNum;
}
public int getNumberOfTransactions() {
return numOfTransactions;
}
public void deposit(double amount){
if (amount<=0) {
System.out.println("Amount to be deposited should be positive");
} else {
balance = balance + amount;
transactions[numOfTransactions] = amount;
transactionsSummary[numOfTransactions] = "$" + Double.toString(amount) + " was deposited.";
numOfTransactions++;
}
}
public void withdraw(double amount)
{
if (amount<=0){
System.out.println("Amount to be withdrawn should be positive");
}
else
{
if (balance < amount) {
System.out.println("Insufficient balance");
} else {
balance = balance - amount;
transactions[numOfTransactions] = amount;
transactionsSummary[numOfTransactions] = "$" + Double.toString(amount) + " was withdrawn.";
numOfTransactions++;
}
}
}
}//end of class
}

To convert an integer to a String:
String out = Integer.toString(n);

You description of case 5 is
Print the detailed account information including last transactions
Just returning the number of transactions as a string is not going to achieve that.
You need to store every transaction as it happens in the transactions array in your BankAccount class and then get the last n values in that array in the gettransactionInfo() function.
EDIT:
And btw, you have forgotten to call the openNewAccount() function

Convert primitive int to its wrapper class and call its toString() method
public String gettransactionInfo(int n) {
return new Integer(n).toString();
}