From e2a4078199cb582e55520107dfdce203e9da9142 Mon Sep 17 00:00:00 2001
From: Dao <comnuoc@users.noreply.gitlab.utu.fi>
Date: Sat, 29 Jun 2024 05:15:17 +0300
Subject: [PATCH] feat(part2): Exercise 4.
---
part_2/exercise_4/.gitignore | 30 +++
part_2/exercise_4/exercise_4.iml | 11 ++
part_2/exercise_4/src/Card.java | 110 +++++++++++
part_2/exercise_4/src/CardId.java | 20 ++
part_2/exercise_4/src/CommandLineApp.java | 175 ++++++++++++++++++
part_2/exercise_4/src/CommandLineHelper.java | 137 ++++++++++++++
part_2/exercise_4/src/Main.java | 6 +
part_2/exercise_4/src/MoneyHelper.java | 14 ++
part_2/exercise_4/src/TicketType.java | 37 ++++
.../exercise_4/src/TicketTypeRepository.java | 56 ++++++
10 files changed, 596 insertions(+)
create mode 100644 part_2/exercise_4/.gitignore
create mode 100644 part_2/exercise_4/exercise_4.iml
create mode 100644 part_2/exercise_4/src/Card.java
create mode 100644 part_2/exercise_4/src/CardId.java
create mode 100644 part_2/exercise_4/src/CommandLineApp.java
create mode 100644 part_2/exercise_4/src/CommandLineHelper.java
create mode 100644 part_2/exercise_4/src/Main.java
create mode 100644 part_2/exercise_4/src/MoneyHelper.java
create mode 100644 part_2/exercise_4/src/TicketType.java
create mode 100644 part_2/exercise_4/src/TicketTypeRepository.java
diff --git a/part_2/exercise_4/.gitignore b/part_2/exercise_4/.gitignore
new file mode 100644
index 0000000..d578053
--- /dev/null
+++ b/part_2/exercise_4/.gitignore
@@ -0,0 +1,30 @@
+### IntelliJ IDEA ###
+/.idea/
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### Eclipse ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
+
+### Mac OS ###
+.DS_Store
\ No newline at end of file
diff --git a/part_2/exercise_4/exercise_4.iml b/part_2/exercise_4/exercise_4.iml
new file mode 100644
index 0000000..c90834f
--- /dev/null
+++ b/part_2/exercise_4/exercise_4.iml
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+ <component name="NewModuleRootManager" inherit-compiler-output="true">
+ <exclude-output />
+ <content url="file://$MODULE_DIR$">
+ <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+ </content>
+ <orderEntry type="inheritedJdk" />
+ <orderEntry type="sourceFolder" forTests="false" />
+ </component>
+</module>
\ No newline at end of file
diff --git a/part_2/exercise_4/src/Card.java b/part_2/exercise_4/src/Card.java
new file mode 100644
index 0000000..0e831df
--- /dev/null
+++ b/part_2/exercise_4/src/Card.java
@@ -0,0 +1,110 @@
+import java.util.Objects;
+import java.util.Optional;
+
+/*
+ * @.classInvariant: getId() != null && getBalanceInCents() >= 0
+ */
+public class Card {
+ private final CardId id;
+ private long balanceInCents = 0;
+ private TicketType lastPurchasedTicketType = null;
+ private long ticketExpiredAt = 0; // number of milliseconds passed since 1970
+
+ /*
+ * @.pre: true
+ * @.post: Object is constructed
+ * throw NullPointerException if id == null
+ */
+ public Card(CardId id) {
+ this.id = Objects.requireNonNull(id, "Id should not be null");
+ }
+
+ /*
+ * @.pre: true
+ * @.post: RESULT != null
+ */
+ public CardId getId() {
+ return id;
+ }
+
+ /*
+ * @.pre: true
+ * @.post: getBalanceInCents() = OLD(getBalanceInCents()) + amountInCents
+ * throw ZeroOrNegativeAmountException if amountInCents <= 0
+ */
+ public void topUp(long amountInCents) throws ZeroOrNegativeAmountException {
+ if (amountInCents <= 0) {
+ throw new ZeroOrNegativeAmountException("Top up amount should be greater than zero");
+ }
+
+ balanceInCents += amountInCents;
+ }
+
+ /*
+ * @.pre: true
+ * @.post: RESULT >= 0
+ */
+ public long getBalanceInCents() {
+ return balanceInCents;
+ }
+
+ /*
+ * @.pre: true
+ * @.post: RESULT == true if a ticket is purchased and is not expired, otherwise RESULT == false
+ */
+ public boolean isTicketValid() {
+ return isTicketPurchased() && !isTicketExpired();
+ }
+
+ /*
+ * @.pre: true
+ * @.post: RESULT == null if there is no ticket
+ */
+ public Optional<TicketType> getLastPurchasedTicketType() {
+ return Optional.ofNullable(lastPurchasedTicketType);
+ }
+
+ /*
+ * @.pre: ticketType != null
+ * @.post: isTicketValid() == true && getBalanceInCents() == OLD(getBalanceInCents()) - ticketType.priceInCents()
+ * throw NotEnoughMoneyForTicketException if getBalanceInCents() < ticketType.priceInCents()
+ */
+ public void buyTicket(TicketType ticketType) throws NotEnoughMoneyForTicketException {
+ if (balanceInCents < ticketType.priceInCents()) {
+ throw new NotEnoughMoneyForTicketException("Your balance is not sufficient for the ticket");
+ }
+
+ balanceInCents -= ticketType.priceInCents();
+ lastPurchasedTicketType = ticketType;
+ ticketExpiredAt = getTimestamp() + ticketType.durationInMilliseconds();
+ }
+
+ @Override
+ public String toString() {
+ return id.toString();
+ }
+
+ private boolean isTicketPurchased() {
+ return null != lastPurchasedTicketType;
+ }
+
+ private boolean isTicketExpired() {
+ return getTimestamp() > ticketExpiredAt;
+ }
+
+ private long getTimestamp() {
+ return System.currentTimeMillis();
+ }
+}
+
+class ZeroOrNegativeAmountException extends RuntimeException {
+ public ZeroOrNegativeAmountException(String message) {
+ super(message);
+ }
+}
+
+class NotEnoughMoneyForTicketException extends RuntimeException {
+ public NotEnoughMoneyForTicketException(String message) {
+ super(message);
+ }
+}
\ No newline at end of file
diff --git a/part_2/exercise_4/src/CardId.java b/part_2/exercise_4/src/CardId.java
new file mode 100644
index 0000000..bc4e957
--- /dev/null
+++ b/part_2/exercise_4/src/CardId.java
@@ -0,0 +1,20 @@
+import java.util.Objects;
+
+/*
+ * @.classInvariant: id() != null
+ */
+public record CardId(Object id) {
+ /*
+ * @.pre: true
+ * @.post: Object is constructed
+ * throw NullPointerException if id == null
+ */
+ public CardId {
+ Objects.requireNonNull(id, "Id should not be null");
+ }
+
+ @Override
+ public String toString() {
+ return id.toString();
+ }
+}
diff --git a/part_2/exercise_4/src/CommandLineApp.java b/part_2/exercise_4/src/CommandLineApp.java
new file mode 100644
index 0000000..22538e9
--- /dev/null
+++ b/part_2/exercise_4/src/CommandLineApp.java
@@ -0,0 +1,175 @@
+import java.util.*;
+
+public class CommandLineApp {
+ private final Card card;
+ private final CommandLineHelper commandLineHelper;
+ private final TicketTypeRepository ticketTypeRepository;
+ private final MoneyHelper moneyHelper;
+
+ public CommandLineApp() {
+ card = createCard();
+ commandLineHelper = new CommandLineHelper();
+ ticketTypeRepository = new TicketTypeRepository();
+ moneyHelper = new MoneyHelper();
+ }
+
+ public void run() {
+ int choice = getMenuChoice();
+ commandLineHelper.clearScreen();
+
+ switch (choice) {
+ case 1:
+ showBalance();
+ break;
+
+ case 2:
+ topUp();
+ break;
+
+ case 3:
+ checkTicketValidity();
+ break;
+ }
+ }
+
+ private int getMenuChoice() {
+ List<String> menu = new ArrayList<>();
+ menu.add("Your card ID: " + card.toString());
+ menu.add(" ");
+ menu.add("1. Show balance");
+ menu.add("2. Top-up");
+ menu.add("3. Buy ticket");
+ menu.add("4. Exit");
+ commandLineHelper.printMenu(menu);
+
+ return commandLineHelper.getIntInput(
+ "Please choose",
+ "Error: please select a number between 1 and 4",
+ (number) -> number >= 1 && number <= 4
+ );
+ }
+
+ private void showBalance() {
+ commandLineHelper.printSuccessMenu("Your balance is: " + moneyHelper.formatCents(card.getBalanceInCents()));
+ System.out.println();
+ run();
+ }
+
+ private void topUp() {
+ boolean isSucceed = false;
+
+ while (true) {
+ try {
+ long euro = commandLineHelper.getLongInput("Please enter amount in Euro", (number) -> number >= 0);
+ long cents = commandLineHelper.getLongInput("Please enter amount in cents", (number) -> number >= 0);
+ long amount = moneyHelper.euroToCent(euro) + cents;
+
+ card.topUp(amount);
+ isSucceed = true;
+
+ break;
+ } catch (ZeroOrNegativeAmountException e) {
+ commandLineHelper.printErrorMessage("Error: " + e.getMessage());
+ String isContinue = commandLineHelper.getStringInput("Do you want to continue? (y/n)");
+
+ if (isContinue.equals("n")) {
+ break;
+ }
+ }
+ }
+
+ if (isSucceed) {
+ commandLineHelper.printSuccessMessage("Top-up successfully");
+ showBalance();
+ return;
+ }
+
+ System.out.println();
+ run();
+ }
+
+ private void checkTicketValidity() {
+ boolean isBuyNewTicket = !card.isTicketValid();
+
+ if (!isBuyNewTicket) {
+ commandLineHelper.printSuccessMessage("Your ticket is still valid. Current ticket type:");
+ commandLineHelper.printSuccessMessage(formatTicketType(card.getLastPurchasedTicketType().get()));
+ String isContinue = commandLineHelper.getStringInput("Do you want to buy another? (y/n)");
+ isBuyNewTicket = isContinue.equals("y");
+ }
+
+ if (isBuyNewTicket) {
+ System.out.println();
+ buyTicket();
+ } else {
+ System.out.println();
+ run();
+ }
+ }
+
+ private void buyTicket() {
+ Optional<TicketType> optChoseType = getChoseTicketType();
+
+ if (optChoseType.isPresent()) {
+ try {
+ card.buyTicket(optChoseType.get());
+ commandLineHelper.printSuccessMessage("Buy ticket successfully");
+ } catch (NotEnoughMoneyForTicketException e) {
+ commandLineHelper.printErrorMessage("Error: " + e.getMessage());
+ }
+ }
+
+ System.out.println();
+ run();
+ }
+
+ private Optional<TicketType> getChoseTicketType() {
+ TicketType choseType = null;
+
+ List<String> menu = new ArrayList<>();
+ menu.add("Ticket types: ");
+ menu.add(" ");
+
+ for (TicketType type: ticketTypeRepository.getAllTypes()) {
+ menu.add(formatTicketType(type));
+ }
+
+ while (true) {
+ try {
+ commandLineHelper.printMenu(menu);
+
+ String typeName = commandLineHelper.getStringInput("Please enter the ticket type name or zero to cancel");
+
+ if (typeName.equals("0")) {
+ break;
+ }
+
+ choseType = ticketTypeRepository.getByName(typeName);
+
+ break;
+ } catch (TicketTypeNotFoundException e) {
+ commandLineHelper.printErrorMessage("Error: " + e.getMessage());
+ String isContinue = commandLineHelper.getStringInput("Do you want to continue? (y/n)");
+
+ if (isContinue.equals("n")) {
+ break;
+ }
+ }
+ }
+
+ return Optional.ofNullable(choseType);
+ }
+
+ private String formatTicketType(TicketType type) {
+ return "Name: '" + type.name()
+ + "'. Description: " + type.description()
+ + ". Price: " + moneyHelper.formatCents(type.priceInCents()) + ".";
+ }
+
+ private Card createCard() {
+ UUID uuid = UUID.randomUUID();
+ CardId cardId = new CardId(uuid);
+
+ return new Card(cardId);
+ }
+}
\ No newline at end of file
diff --git a/part_2/exercise_4/src/CommandLineHelper.java b/part_2/exercise_4/src/CommandLineHelper.java
new file mode 100644
index 0000000..77a0405
--- /dev/null
+++ b/part_2/exercise_4/src/CommandLineHelper.java
@@ -0,0 +1,137 @@
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Scanner;
+import java.util.function.Predicate;
+
+public class CommandLineHelper {
+ private final String ANSI_RESET = "\u001B[0m";
+ private final String ANSI_GREEN = "\u001B[32m";
+ private final String ANSI_RED = "\u001B[31m";
+
+ private final Scanner reader;
+
+ public CommandLineHelper() {
+ reader = new Scanner(System.in);
+ }
+
+ public void printMenu(List<String> strings) {
+ this.printMenu(strings, '*');
+ }
+
+ public void printMenu(List<String> strings, char character) {
+ int maxLen = strings.stream()
+ .mapToInt(String::length)
+ .max()
+ .orElse(0);
+
+ System.out.println(repeatCharacter(character, maxLen + 4));
+
+ for (String str: strings) {
+ System.out.println(
+ character + " " + str
+ + repeatCharacter(' ', maxLen - str.length())
+ + " " + character
+ );
+ }
+
+ System.out.println(repeatCharacter(character, maxLen + 4));
+ }
+
+ public void printMenu(List<String> strings, char character, String color) {
+ System.out.print(color);
+ printMenu(strings, character);
+ System.out.print(ANSI_RESET);
+ }
+
+ public void printMenu(List<String> strings, String color) {
+ this.printMenu(strings, '*', color);
+ }
+
+ public void printMenu(String string, String color) {
+ List<String> messages = new ArrayList<>();
+ messages.add(string);
+
+ printMenu(messages, color);
+ }
+
+ public void printSuccessMenu(String string) {
+ printMenu(string, ANSI_GREEN);
+ }
+
+ public void printSuccessMessage(String string) {
+ System.out.println(ANSI_GREEN + string + ANSI_RESET);
+ }
+
+ public void printErrorMessage(String string) {
+ System.out.println(ANSI_RED + string + ANSI_RESET);
+ }
+
+ public String repeatCharacter(char character, int number) {
+ if (number <= 0) {
+ return "";
+ }
+
+ char[] repeat = new char[number];
+ Arrays.fill(repeat, character);
+
+ return new String(repeat);
+ }
+
+ public void clearScreen() {
+ System.out.print("\033[H\033[2J");
+ System.out.flush();
+ }
+
+ public String getStringInput(String message) {
+ System.out.print(message + ": ");
+
+ return reader.nextLine();
+ }
+
+ public int getIntInput(String message, String errorMessage, Predicate<Integer> tester) {
+ int input;
+
+ while (true) {
+ try {
+ System.out.print(message + ": ");
+ input = Integer.parseInt(reader.nextLine());
+
+ if (null == tester || tester.test(input)) {
+ break;
+ }
+
+ printErrorMessage(errorMessage);
+ } catch (NumberFormatException e) {
+ printErrorMessage(errorMessage);
+ }
+ }
+
+ return input;
+ }
+
+ public long getLongInput(String message, Predicate<Long> tester) {
+ return getLongInput(message, "Error: please enter a number", tester);
+ }
+
+ public long getLongInput(String message, String errorMessage, Predicate<Long> tester) {
+ long input;
+
+ while (true) {
+ try {
+ System.out.print(message + ": ");
+ input = Long.parseLong(reader.nextLine());
+
+ if (null == tester || tester.test(input)) {
+ break;
+ }
+
+ printErrorMessage(errorMessage);
+ } catch (NumberFormatException e) {
+ printErrorMessage(errorMessage);
+ }
+ }
+
+ return input;
+ }
+}
\ No newline at end of file
diff --git a/part_2/exercise_4/src/Main.java b/part_2/exercise_4/src/Main.java
new file mode 100644
index 0000000..df4ad8d
--- /dev/null
+++ b/part_2/exercise_4/src/Main.java
@@ -0,0 +1,6 @@
+public class Main {
+ public static void main(String[] args) {
+ CommandLineApp app = new CommandLineApp();
+ app.run();
+ }
+}
\ No newline at end of file
diff --git a/part_2/exercise_4/src/MoneyHelper.java b/part_2/exercise_4/src/MoneyHelper.java
new file mode 100644
index 0000000..d6674f0
--- /dev/null
+++ b/part_2/exercise_4/src/MoneyHelper.java
@@ -0,0 +1,14 @@
+import java.text.NumberFormat;
+import java.util.Locale;
+
+public class MoneyHelper {
+ public long euroToCent(long euro) {
+ return euro * 100;
+ }
+
+ public String formatCents(long cents) {
+ NumberFormat nf = NumberFormat.getCurrencyInstance(Locale.FRANCE);
+
+ return nf.format(cents / 100.0);
+ }
+}
diff --git a/part_2/exercise_4/src/TicketType.java b/part_2/exercise_4/src/TicketType.java
new file mode 100644
index 0000000..f77e3a1
--- /dev/null
+++ b/part_2/exercise_4/src/TicketType.java
@@ -0,0 +1,37 @@
+import java.util.Objects;
+
+/*
+ * @.classInvariant: name() != null && durationInMilliseconds() > 0 && priceInCents() >= 0
+ */
+public record TicketType(String name, String description, long durationInMilliseconds, long priceInCents) {
+ /*
+ * @.pre: true
+ * @.post: Object is constructed
+ * throw NullPointerException if name == null
+ * throw ZeroOrNegativeDurationException if durationInMilliseconds <= 0
+ * throw NegativePriceException if priceInCents < 0
+ */
+ public TicketType {
+ Objects.requireNonNull(name, "Id should not be null");
+
+ if (durationInMilliseconds <= 0) {
+ throw new ZeroOrNegativeDurationException("Duration should be greater than zero");
+ }
+
+ if (priceInCents < 0) {
+ throw new NegativePriceException("Price should be greater than or equal to zero");
+ }
+ }
+}
+
+class ZeroOrNegativeDurationException extends RuntimeException {
+ public ZeroOrNegativeDurationException(String message) {
+ super(message);
+ }
+}
+
+class NegativePriceException extends RuntimeException {
+ public NegativePriceException(String message) {
+ super(message);
+ }
+}
\ No newline at end of file
diff --git a/part_2/exercise_4/src/TicketTypeRepository.java b/part_2/exercise_4/src/TicketTypeRepository.java
new file mode 100644
index 0000000..570dca3
--- /dev/null
+++ b/part_2/exercise_4/src/TicketTypeRepository.java
@@ -0,0 +1,56 @@
+import java.util.ArrayList;
+import java.util.List;
+
+public class TicketTypeRepository {
+ private final List<TicketType> types;
+
+ public TicketTypeRepository() {
+ types = new ArrayList<>();
+ types.add(new TicketType(
+ "single",
+ "Single ticket. Valid for 2 hours",
+ (long) 2 * 60 * 60 * 1000,
+ 3 * 100
+ ));
+ types.add(new TicketType(
+ "day",
+ "Day ticket. Valid for 24 hours",
+ (long) 24 * 60 * 60 * 1000,
+ 8 * 100
+ ));
+ types.add(new TicketType(
+ "monthly",
+ "Monthly ticket. Valid for 30 days",
+ (long) 30 * 24 * 60 * 60 * 1000,
+ 55 * 100
+ ));
+ }
+
+ public List<TicketType> getAllTypes() {
+ return types;
+ }
+
+ /*
+ * @.pre: name != null
+ * @.post: RESULT != null
+ * throw TicketTypeNotFoundException if there is no ticket type with this name.
+ */
+ public TicketType getByName(String name) {
+ List<TicketType> result = types.stream()
+ .filter((type) -> type.name().equals(name))
+ .limit(2)
+ .toList();
+
+ if (result.isEmpty()) {
+ throw new TicketTypeNotFoundException("Ticket type '" + name + "' is not found");
+ }
+
+ return result.getFirst();
+ }
+}
+
+class TicketTypeNotFoundException extends RuntimeException {
+ public TicketTypeNotFoundException(String message) {
+ super(message);
+ }
+}
--
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