Einführung in die objektorientierte Programmierung

Aufgabe 1

public class Foo {
  private int x;
  private static char c = 'c';
  Foo(int x) {
    this.x = x;
  }
  Foo() {
    x = 42;
  }
  class Bar {
    Object y;
    void m(Foo foo) {
      y = new Object();
    }
    void m(String foo) {
      y = foo;
    }
    Bar() {
      y = new Object();
    }
  }
  Object z() {
    return new String();
  }
  static class X {
    void n() {
      System.out.println(x);
      System.out.println(c);
    }
  }
}

Aufgabe 3

class BinaryNode {
  private BinaryNode leftSon, rightSon;
  private int value;
  public BinaryNode(int v) {
    value = v;
  }
  public boolean contains(int v) {
    if (value==v) {
      return true;
    } // end of if
    else {
      if (value<v) {
        if (rightSon==null) {
          return false;
        } // end of if
        else {
          return rightSon.contains(v);
        } // end of if-else
      } // end of if
      else {
        if (leftSon==null) {
          return false;
        } // end of if
        else {
          return leftSon.contains(v);
        } // end of if-else
      } // end of if-else
    } // end of if-else
  }
  public void insert(int v) { 
    BinaryNode stelle=this;
    BinaryNode neu;
    while ((v<stelle.value && stelle.leftSon!=null)
    || (v>stelle.value && stelle.rightSon!=null)) { 
      if (v<stelle.value) {
        stelle=stelle.leftSon;
      } // end of if
      else {
        stelle=stelle.rightSon;
      } // end of if-else
    } // end of while
    neu= new BinaryNode(v);
    if (v<stelle.value) {
      stelle.leftSon= neu;
    } // end of if
    else {
      stelle.rightSon= neu;
    } // end of if-else 
  }
  public void inorder() { 
    if (leftSon!=null) {
      leftSon.inorder();
    } // end of if
    System.out.println(value);
    if (rightSon!=null) {
      rightSon.inorder();
    } // end of if
  }
}


public class TestTree {
  public static void main(String[] args) {
    BinaryNode myTree = new BinaryNode(6);
    myTree.insert(5);
    myTree.insert(4);
    myTree.insert(12);
    myTree.insert(11);
    myTree.insert(10);
    System.out.println(myTree.contains(17));
    myTree.inorder();
  }
}

Aufgabe 4

interface Car {
  String readMotorPowerInKiloWatt();
}

class RealCar implements Car {
  private double power;
  public RealCar(double power) {
    this.power = power;
  }
  public String readMotorPowerInKiloWatt() {
    return "Car: My power is " + power + " KW!";
  }
  // Methode zum Tunen des Autos
  public void tunePower() {
    power = power * 1.2;
  }
}

class CarFactory {
  public Car giveMeACar() {
    return new RealCar(98);
  }
}

class Main{
  public static void main(String[] args){
    // Fabrik erzeugen
    CarFactory fabrik= new CarFactory();
    //Auto erzeugen
    //Car auto=  fabrik.giveMeACar();
    RealCar auto= (RealCar) fabrik.giveMeACar();
    System.out.println(auto.readMotorPowerInKiloWatt());
    //Tunen
    auto.tunePower();
    System.out.println(auto.readMotorPowerInKiloWatt());
    
  }
}