#java #hashmap
#java #хэш-карта
Вопрос:
У меня есть хэш-карта, которая содержит идентификатор для ключа и клиента в качестве значения. У клиента есть один или несколько банковских счетов. У меня есть отдельный класс Account, в котором есть сведения об учетной записи. Мой класс Client имеет доступ к классу Account, а учетные записи создаются из конструктора в классе Driver. Я хотел бы получить доступ к коллекции учетных записей клиента, но каждый раз, когда я пытаюсь, мне возвращается только одна учетная запись, вместо того, чтобы иметь доступ к любой или ко всем из них. Я создаю учетные записи в классе драйверов и устанавливаю каждую учетную запись для клиента. Есть идеи, как я могу получить доступ к любой или всем учетным записям?
import java.util.ArrayList;
public class ATM {
private InputReader reader;
private String accountNumber;
private String passcode;
private boolean customerVerified;
private String customerId;
private Bank theBank;
private Bank theBanks;
private Customer currentCustomer;
private final int senior = 65;
/**
* Default constructor. Calls the initialize() method to seed the Bank with
* some Customers. Calls the run() method to perform the primary program
* functions.
*/
public ATM() {
super();
initialize();
run();
}
/**
* Main method calls the class default constructor.
* @param args for program arguments (not used)
*/
public static void main(String[] args) {
new ATM();
}
/**
* The primary application processor. All application functions are c alled
* from here. Uses a loop to prompt users to perform banking transactions.
* Must use switch/case selection to determine uses choices.
*/
public void run() {
reader = new InputReader();
boolean exit = false;
System.out.println("Welcome to Bullwinkle's Bank.");
while (!exit) {
System.out.println("Choose one of the following options:");
System.out.println("1 - Sign In");
System.out.println("2 - Deposit");
System.out.println("3 - Withdraw");
System.out.println("4 - Display Account Info");
System.out.println("5 - Exit");
System.out.print("> ");
int choice = reader.getIntInput();
switch (choice) {
case 1:
choice = 1;
verifyCustomer();
break;
case 2:
choice = 2;
transactDeposit();
break;
case 3:
choice = 3;
transactWithdraw();
break;
case 4:
choice = 4;
displayAccountInformation();
break;
case 5:
choice = 5;
System.out
.println("Thank you for banking at Bullwinkle's Bank");
System.out
.println("DEBUG: Displaying all the accounts in the bank.");
Bank.displayAllCustomers();
System.exit(0);
}
}
}
/**
* Creates Customer objects by calling overloaded constructor.
* creates Account objects by calling overloaded constructor.
* Sets Accounts to Customers.
* Adds Customer references to the Back HashMap as seed data for testing.
*/
public void initialize() {
theBank = new Bank();
Customer myia = new Customer("Myia", "Dog", "456", "123", 65);
if (myia.getAge() >= senior) {
ArrayList<Account> accounts = new ArrayList<Account>();
accounts.add(new SavingsAccount("SA-123", 0.0));
accounts.add(new GoldAccount("GL-123", 0.0, .01, false));
for (int j = 0; j < accounts.size(); j ) {
Account act = accounts.get(j);
myia.setAccount(act);
theBank.addCustomer(myia);
System.out.println(myia);
}
}/*
Customer freckle = new Customer("Freckle", "Cat", "789", "3", 22);
freckle.setAccount(new SavingsAccount("SA-789", 0.0));
theBank.addCustomer(freckle);
*/
/*Customer[] cust = {new Customer("Freckle", "Cat", "123", "1", 22), new Customer("Myia", "Dog", "456", "2", 65)};
Account[] acct = { new SavingsAccount("SA-123", 0.0), new ChequingAccount("CH-123", 0.0, 3)};
for(int i = 0; i < cust.length; i ) {
cust[i].setAccount(acct[i]);
}
for (Customer customer : cust) {
theBank.addCustomer(customer);
}*/
}
/**
* Performs a deposit into a Customer's account. Checks to see if the
* customer has signed in. If not, then verifyCustomer() is called and the menu
* is displayed again.
*/
public void transactDeposit() {
if (customerVerified) {
System.out.println("Enter the amount to deposit: ");
currentCustomer.getAccount().addToBalance(reader.getDoubleInput());
} else {
System.out
.println("ERROR: You must LOGIN before you can perform a transaction.");
verifyCustomer();
}
}
/**
* Performs a withdrawal from a Customer's account. Checks to see if the
* customer has signed in. If not, then verifyCustomer() is called and the menu
* is displayed again.
*/
public void transactWithdraw() {
if (customerVerified) {
System.out.println("Enter the amount to withdraw: ");
double amount = reader.getDoubleInput();
if (amount <= currentCustomer.getAccount().getBalance()) {
currentCustomer.getAccount().subtractFromBalance(amount);
} else {
System.out
.println("ERROR: You have insufficinet funds to withdraw that amount.");
}
} else {
System.out
.println("ERROR: You must LOGIN before you can perform a transaction.");
verifyCustomer();
}
}
/**
* Displays a Customer's information if the customer has been
* previously verified.
*/
public void displayAccountInformation() {
if (customerVerified) {
System.out.println("Here is your information.");
Bank.displayCustomerInformation(currentCustomer);
} else {
System.out
.println("ERROR: You must LOGIN before you can perform a transaction.");
verifyCustomer();
}
}
/**
* Confirms a Customer's account number and passcode. Called when the
* user is required to sign in to the application. Will set a boolean so the
* user does not have to sign in again during the session.
*/
public void verifyCustomer() {
System.out.println("Enter CustomerID: ");
customerId = reader.getStringInput();
System.out.println("Enter Passcode: ");
passcode = reader.getStringInput();
System.out.println("Enter AccountNumber");
accountNumber = reader.getStringInput();
currentCustomer = Bank.theBank.get(customerId);
if (currentCustomer != null) {
if (passcode.equals(currentCustomer.getPasscode())) {
customerVerified = true;
} else{
System.out.println("ERROR: Either account number or passcode is not correct.");
run();
}
} else {
System.out.println("ERROR: Either account number or passcode is not correct.");
run();
}
}
}
import java.util.HashMap;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class Bank {
private ATM atm;
/**
* The bank collection to hold all Customer data.
* Uses a customer's account number as key and the Customer reference as the value.
*/
public static HashMap<String, Customer > theBank;
public static HashMap<String, HashMap<String, Customer>> theBanks;
public static ArrayList<Customer> bankster;
/**
* Default constructor for Bank class.
* Initializes the HashMap
*/
public Bank() {
super();
theBank = new HashMap<String, Customer>();
bankster = new ArrayList<Customer>();
theBanks = new HashMap<String, HashMap<String, Customer>>();
}
/**
* Add a new Customer to the HashMap.
* @param newCustomer The new element to add to the HashpMap using
* the account number as the key and the new Customer as the value.
* @param string
*/
public void addCustomer(Customer newCustomer) {
if (newCustomer != null) {
theBank.put(newCustomer.getCustomerId(), newCustomer);
}
}
/**
* Removes an Customer from the HashMap.
* @param accountNumber The key of the element to remove from the HashMap.
*/
public void closeAccount(String customerId, String accountNumber) {
if (accountNumber != null amp;amp; customerId != null) {
theBank.get(customerId).getAccount().setActive(false);
}
}
/**
* Displays the details of a Customer element in the HshMap.
* Uses Customer.toString() implementation.
* @param customer the Customer chosen to display.
*/
public static void displayCustomerInformation(Customer customer){
if(customer != null){
System.out.println(customer.getAccount().getAccountNumber());
System.out.println(customer.toString());
System.out.println(customer);
}
}
/**
* Displays all elements of the HashMap by using Customer.toString()
* implementation of each.
*/
public static void displayAllCustomers(){
for(Customer customer : theBank.values()){
System.out.println(customer);
for (HashMap<String, Customer> custy : theBanks.values()) {
System.out.println(custy);
}
for (Customer custer : bankster) {
System.out.println(custer);
}
}
}
}
import java.util.*;
public class Customer {
private String firstName;
private String lastName;
private String passcode;
private Account account;
private int age;
private String customerId;
/**
* Default constructor for a Customer. Sets the fields to the default values
* for each type.
*/
public Customer() {
super();
}
/**
* @param firstName
* String to initialize the firstName field
* @param lastName
* String to initialize the lastName field
* @param passcode
* String to initialize the passcode field
*/
public Customer(String firstName, String lastName, String passcode, String customerId, int age) {
super();
setFirstName(firstName);
setLastName(lastName);
setPasscode(passcode);
setAge(age);
setCustomerId(customerId);
account = new Account();
setAccount(account);
}
/**
* Accessor for a Cutomer's collection of Accounts
*
* @return a customer account as an Account
*/
public Account getAccount() {
return account;
}
public int getAge() {
return age;
}
public void setAge(int age) {
if (age > 17 amp;amp; age <= 120) {
this.age = age;
}
}
public String getCustomerId() {
return customerId;
}
public void setCustomerId(String customerId) {
if (customerId != null) {
this.customerId = customerId;
}
}
/**
* Mutator for the Account filed
*
* @param account
* the Account to set
*/
public void setAccount(Account account) {
if (account != null) {
this.account = account;
}
}
/**
* Accessor method for the firstName field
*
* @return the firstName as a String
*/
public String getFirstName() {
return firstName;
}
/**
* Mutator for the firstName field
*
* @param firstName
* the firstName to set
*/
public void setFirstName(String firstName) {
if (firstName != null amp;amp; !firstName.trim().isEmpty()) {
this.firstName = firstName;
}
}
/**
* Accessor method for the lastName
*
* @return the lastName as a String
*/
public String getLastName() {
return lastName;
}
/**
* Mutator for the lastName field
*
* @param lastName
* the lastName to set
*/
public void setLastName(String lastName) {
if (lastName != null amp;amp; !lastName.trim().isEmpty()) {
this.lastName = lastName;
}
}
/**
* Accessor method for the passcode field
*
* @return the passcode as a String
*/
public String getPasscode() {
return passcode;
}
/**
* Mutator for the passcode field
*
* @param passcode
* the passcode to set
*/
public void setPasscode(String passcode) {
if (passcode != null amp;amp; !passcode.trim().isEmpty()) {
this.passcode = passcode;
}
}
/* (non-Javadoc)
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
return "Customer [firstName=" firstName ", lastName=" lastName ", passcode=" passcode ", account="
account ", age=" age ", customerId=" customerId ", toString()=" super.toString() "]";
}
}
------
import java.util.ArrayList;
import java.util.Date;
public class Account {
private String accountNumber;
private double balance;
private boolean active;
protected ArrayList<String>transactions;
/**
* Default constructor to create Account objects
*/
public Account() {
super();
transactions = new ArrayList<String>();
}
/**
* Overloaded Account constructor
*
* @param accountNumber
* to set the accountNumber field
* @param balance
* to set the balance field
*/
public Account(String accountNumber, double balance) {
super();
setAccountNumber(accountNumber);
setBalance(balance);
transactions = new ArrayList<String>();
active = true;
}
public void setAccountNumber(String accountNumber) {
if (accountNumber != null) {
this.accountNumber = accountNumber;
}
}
/**
* accessor for the accountNumber field
*
* @return the accountNumber as a String
*/
public String getAccountNumber() {
return accountNumber;
}
/**
* accessor for the balance field
*
* @return the balance as a double
*/
public double getBalance() {
return balance;
}
/**
* accessor for the active field
*
* @return the active boolean
*/
public boolean isActive() {
return active;
}
/**
* mutator fir the balance field
*
* @param balance
* the balance to set
*/
public void setBalance(double balance) {
if(balance >= 0){
this.balance = balance;
}
}
/**
* mutator for the active field
*
* @param active
* the active to set
*/
public void setActive(boolean active) {
this.active = active;
}
/**
* Adds to an Account balance
*
* @param amount
* a double to add to the existing balance field
*/
public void addToBalance(double amount) {
if (amount > 0) {
balance = amount;
addTransactionInfo(String.format("%s - deposit: $%.2f", new Date(), amount));
}
}
/**
* Subtracts from an Account balance
*
* @param amount
* a double to subtract from the balance field
*/
public void subtractFromBalance(double amount) {
if (amount > 0 amp;amp; balance - amount > 0) {
balance -= amount;
addTransactionInfo(String.format("%s - deposit: $%.2f", new Date(), amount));
}
}
/**
* method to add to transaction information
* @param transaction
*/
public void addTransactionInfo(String addTransaction) {
if (addTransaction != null) {
transactions.add(addTransaction);
}
}
/**
* Method to display the transactions
*/
public void displayAccountRecords() {
if (transactions.size() > 0) {
for (String transacts : transactions) {
System.out.println(transacts);
}
}
}
@Override
public String toString() {
return "Account [accountNumber=" accountNumber ", balance=" balance ", active=" active
", transactions=" transactions "]";
}
------
import java.util.Date;
public class ChequingAccount extends Account {
private final double FEE = 5.0;
private int numberOfCheques;
public ChequingAccount() {
super();
}
public ChequingAccount(String accountNumber, double balance, int numberOfCheques) {
super(accountNumber, balance);
setNumberOfCheques(numberOfCheques);
}
public int getNumberOfCheques() {
return numberOfCheques;
}
public void setNumberOfCheques(int numberOfCheques) {
if (numberOfCheques >= 0) {
this.numberOfCheques = numberOfCheques;
}
}
public double getFEE() {
return FEE;
}
/**
* Adds to an Account balance
*
* @param amount
* a double to add to the existing balance field
*/
public void addToBalance(double amount) {
if (amount > 0) {
super.addToBalance(amount);
addTransactionInfo(new Date() " Deposit: $" amount);
}
}
/**
* Subtracts from an Account balance
*
* @param amount
* a double to subtract from the balance field
*/
public void subtractFromBalance(double amount) {
if (super.getBalance() - amount - FEE > 0) {
super.subtractFromBalance(amount FEE);
}else if (super.getBalance() - amount - FEE < 0) {
if (super.getBalance() - FEE > 0) {
super.subtractFromBalance(0 FEE);
}
}
}
@Override
public String toString() {
return "ChequingAccount [FEE=" FEE ", numberOfCheques=" numberOfCheques ", toString()="
super.toString() "]";
}
}
-------
Комментарии:
1. Ммм…. Как у вас есть оператор if сразу после
public class Driver2. это всего лишь фрагменты кода, вам нужен полный код?
3. Конечно, я имею в виду, я думаю, что это необходимо, для меня это не имеет смысла… Извините, QAQ
Ответ №1:
По сути, что вам нужно сделать, так это то, что класс Client должен иметь набор, содержащий данные учетной записи для клиента.
public class Client {
....
private fields
....
private Set<Account> clientAccount;
}
Карта будет выглядеть следующим образом :
Map<Integer, Client>
или, что более предпочтительно, с случайно сгенерированными хэшированными идентификаторами клиентов, [как у нас в мире блокчейнов]
Map<String, client>
После того, как у вас будет такая договоренность, вы можете легко получить учетные записи для любого идентификатора клиента, который вы хотите.
Надеюсь, что это поможет..
Комментарии:
1. кстати, «..» выглядит великолепно, как ты так быстро прочитал ?_?
2. Спасибо 🙂 Я просто попытался быстро разобраться в проблеме.