added uebung07 angabe

uebung07/src/oop/ch05/mensa/AccountCard.java

@@ -0,0 +1,34 @@
+package oop.ch05.mensa;
+
+import oop.ch05.secured.AuthorizationException;
+import oop.ch05.secured.SecuredContent;
+import oop.ch05.secured.SecurityClient;
+
+public class AccountCard extends MensaCard {
+  private final SecuredContent account;
+
+  public AccountCard(String key, String account, int password) {
+    super(key, Color.white);
+    this.account = new SecuredContent(password, account);
+  }
+
+  public String getAccount() {
+    return (String) account.getContent();
+  }
+
+  public void setAccount(SecurityClient client, String account) throws AuthorizationException {
+    if (account == null || account.trim().length() == 0)
+      throw new IllegalArgumentException("Invalid account " + account);
+    this.account.setContent(client, account);
+  }
+
+  @Override
+  public String toString() {
+    return super.toString() + " for account " + account.getContent();
+  }
+
+  @Override
+  public void pass(CashPoint cashPoint) {
+    cashPoint.charge(this);
+  }
+}

uebung07/src/oop/ch05/mensa/CashCard.java

@@ -0,0 +1,43 @@
+package oop.ch05.mensa;
+
+import oop.ch05.secured.AuthorizationException;
+import oop.ch05.secured.SecuredContent;
+
+public class CashCard extends MensaCard {
+  private final SecuredContent balance;
+
+  public CashCard(String key, Color color, int password) {
+    super(key, color);
+    balance = new SecuredContent(password, 0);
+    if (color != Color.blue && color != Color.green)
+      throw new IllegalArgumentException("Invalid CashCard color " + color);
+  }
+
+  public int getBalance() {
+    return (Integer) balance.getContent();
+  }
+
+  void deposit(VendingMachine client, int cents)
+      throws AuthorizationException {
+    if (cents <= 0)
+      throw new IllegalArgumentException("Non-positive deposit");
+    final int newBalance = getBalance() + cents;
+    balance.setContent(client, newBalance);
+  }
+
+  void charge(CashPoint client, int cents) throws AuthorizationException {
+    if (cents < 0)
+      throw new IllegalArgumentException("Negative charge");
+    balance.setContent(client, getBalance() - cents);
+  }
+
+  @Override
+  public String toString() {
+    return super.toString() + " with " + balance.getContent() + " cents";
+  }
+
+  @Override
+  public void pass(CashPoint cashPoint) throws AuthorizationException, RejectedException {
+    cashPoint.charge(this);
+  }
+}

uebung07/src/oop/ch05/mensa/CashPoint.java

@@ -0,0 +1,64 @@
+package oop.ch05.mensa;
+
+import oop.ch05.secured.AuthorizationException;
+import oop.ch05.secured.SecurityClient;
+
+public class CashPoint implements SecurityClient {
+  private final int password;
+  public final String name;
+  private int counter;
+  private int cents;
+
+  public CashPoint(String name, int password) {
+    this.name = name;
+    this.password = password;
+    this.counter = 0;
+    this.cents = 0;
+  }
+
+  @Override
+  public int challengeResponse(int challenge) {
+    return challenge ^ password;
+  }
+
+  @Override
+  public String toString() {
+    return "Cash point " + name + " (" + getCounter() + " meals, " + getCents() + " cents charged)";
+  }
+
+  public int getCounter() {
+    return counter;
+  }
+
+  public int getCents() {
+    return cents;
+  }
+
+  private int getPrice(Color color) {
+    return switch (color) {
+      case green -> 267;
+      case blue -> 357;
+      case white -> 495;
+      default -> 0;
+    };
+  }
+
+  void count(MensaCard card) {
+    counter++;
+  }
+
+  void charge(CashCard cashCard) throws AuthorizationException, RejectedException {
+    final int price = getPrice(cashCard.color);
+    if (cashCard.getBalance() < price)
+      throw new RejectedException("insufficient payment");
+    cashCard.charge(this, price);
+    count(cashCard);
+    cents += price;
+  }
+
+  void charge(AccountCard accountCard) {
+    final int price = getPrice(accountCard.color);
+    System.out.println("Charging " + price + " cents on account " + accountCard.getAccount());
+    cents += price;
+  }
+}

uebung07/src/oop/ch05/mensa/Color.java

@@ -0,0 +1,5 @@
+package oop.ch05.mensa;
+
+public enum Color {
+  green, red, blue, white, gray
+}

uebung07/src/oop/ch05/mensa/CountCard.java

@@ -0,0 +1,15 @@
+package oop.ch05.mensa;
+
+public class CountCard extends MensaCard {
+
+  public CountCard(String key, Color color) {
+    super(key, color);
+    if (color != Color.red && color != Color.gray)
+      throw new IllegalArgumentException("Invalid CountCard color " + color);
+  }
+
+  @Override
+  public void pass(CashPoint cashPoint) {
+    cashPoint.count(this);
+  }
+}

uebung07/src/oop/ch05/mensa/MensaCard.java

@@ -0,0 +1,20 @@
+package oop.ch05.mensa;
+
+import oop.ch02.cards.Card;
+import oop.ch05.secured.AuthorizationException;
+
+public abstract class MensaCard extends Card {
+  public final Color color;
+
+  protected MensaCard(String name, Color color) {
+    super(name);
+    this.color = color;
+  }
+
+  @Override
+  public String toString() {
+    return color + " card " + getNumber() + " (" + getName() + ")";
+  }
+
+  public abstract void pass(CashPoint cashPoint) throws RejectedException, AuthorizationException;
+}

uebung07/src/oop/ch05/mensa/MensaExample.java

@@ -0,0 +1,68 @@
+package oop.ch05.mensa;
+
+import oop.ch05.secured.AuthorizationException;
+
+public class MensaExample {
+  public static void main(String[] args) {
+    VendingMachine vm1 = new VendingMachine("left", 4711);
+    VendingMachine vm2 = new VendingMachine("right", 4711);
+    VendingMachine tumVM = new VendingMachine("TUM Mensa", 3141);
+    CashPoint unibwMensa = new CashPoint("UniBw Mensa", 4711);
+
+    AccountCard conf = new AccountCard("conference", "33-1298", 42);
+    MensaCard frankSmith = new CountCard("Frank Smith", Color.gray);
+    CashCard hansMueller = new CashCard("Hans Müller", Color.green, 4711);
+    CashCard peterSchmidt = new CashCard("Peter Schmidt", Color.green, 4711);
+    CashCard thomasMayer = new CashCard("Thomas Mayer", Color.blue, 4711);
+
+    deposit(vm1, hansMueller, 10);
+    deposit(vm1, peterSchmidt, 5);
+    deposit(vm2, thomasMayer, 2);
+    deposit(tumVM, hansMueller, 10);
+
+    System.out.println(vm1);
+    System.out.println(vm2);
+    System.out.println(tumVM);
+    System.out.println(hansMueller);
+    System.out.println(peterSchmidt);
+    System.out.println(thomasMayer);
+    System.out.println();
+
+    pass(hansMueller, unibwMensa);
+    System.out.println(hansMueller);
+    System.out.println(unibwMensa);
+
+    pass(frankSmith, unibwMensa);
+    pass(conf, unibwMensa);
+    pass(thomasMayer, unibwMensa);
+    pass(hansMueller, unibwMensa);
+    pass(hansMueller, unibwMensa);
+    pass(hansMueller, unibwMensa);
+
+    System.out.println(unibwMensa);
+    System.out.println(hansMueller);
+    System.out.println(peterSchmidt);
+    System.out.println(thomasMayer);
+  }
+
+  private static void pass(MensaCard mensaCard, CashPoint cashPoint) {
+    try {
+      mensaCard.pass(cashPoint);
+    }
+    catch (RejectedException e) {
+      System.out.println("rejected: " + e.getMessage());
+    }
+    catch (AuthorizationException e) {
+      System.out.println("authrozation failed: " + e.getMessage());
+    }
+  }
+
+  private static void deposit(VendingMachine vm, CashCard cashCard, int euros) {
+    try {
+      vm.deposit(cashCard, euros);
+    }
+    catch (AuthorizationException e) {
+      System.out.println("authorization failed: " + e.getMessage());
+    }
+  }
+}

uebung07/src/oop/ch05/mensa/RejectedException.java

@@ -0,0 +1,7 @@
+package oop.ch05.mensa;
+
+public class RejectedException extends Exception {
+  public RejectedException(String message) {
+    super(message);
+  }
+}

uebung07/src/oop/ch05/mensa/VendingMachine.java

@@ -0,0 +1,37 @@
+package oop.ch05.mensa;
+
+import oop.ch05.secured.AuthorizationException;
+import oop.ch05.secured.SecurityClient;
+
+public class VendingMachine implements SecurityClient {
+  private final int password;
+  public final String name;
+  private int euros;
+
+  public VendingMachine(String name, int password) {
+    this.name = name;
+    this.password = password;
+    this.euros = 0;
+  }
+
+  @Override
+  public int challengeResponse(int challenge) {
+    return challenge ^ password;
+  }
+
+  @Override
+  public String toString() {
+    return "Vending machine " + name + " (contains EUR " + euros + ")";
+  }
+
+  public int getEuros() {
+    return euros;
+  }
+
+  public void deposit(CashCard card, int euros) throws AuthorizationException {
+    if (euros <= 0)
+      throw new IllegalArgumentException("Non-positive deposit");
+    card.deposit(this, euros * 100);
+    this.euros += euros;
+  }
+}