update exercises

Author: SteffenLm

Car.java

@@ -1,6 +1,6 @@
 public final class Car extends Vehicle {
 
-  private int seats;
+  private final int seats;
 
   public Car(String make, String model, Engine engine, int seats) {
     super(make, model, engine);
@@ -12,25 +12,24 @@ public int getSeats() {
   }
 
   public void doATurboBoost() {
-    speed *= 2;
+    speedInKmh *= 2;
     System.out.println(
         getMake()
             + " "
             + getModel()
             + " macht einen Turboboost und beschleunigt auf "
-            + speed
+            + speedInKmh
             + " km/h");
   }
 
-  public void print() {
-    System.out.println(
-        getMake()
-            + " "
-            + getModel()
-            + " ("
-            + getEngine().getDescription()
-            + ", "
-            + seats
-            + " Sitzplaetze)");
+  public String toString() {
+    return getMake()
+        + " "
+        + getModel()
+        + " ("
+        + getEngine().getDescription()
+        + ", "
+        + seats
+        + " Sitzplaetze)";
   }
 }

Engine.java

@@ -4,7 +4,7 @@ public enum Engine {
   GAS("Gas"),
   ELECTRO("Elektro");
 
-  private String description;
+  private final String description;
 
   Engine(String description) {
     this.description = description;

Exercise.java

@@ -7,10 +7,20 @@ public static void main(String[] args) {
     Truck truck1 = new Truck("MAN", "TGX", Engine.DIESEL, 20);
     Car car2 = new Car("Opel", "Zafira Life", Engine.DIESEL, 7);
 
+    System.out.println("Anzahl Fahrzeuge: " + Vehicle.getNumberOfVehicles());
+
+    System.out.println(car1.toString());
+    System.out.println(truck1.toString());
+    System.out.println(car2.toString());
+
+    car1.accelerate(50);
+    truck1.transform();
+    car1.doATurboBoost();
+    truck1.transform();
     rental.addVehicle(car1);
     rental.addVehicle(truck1);
     rental.addVehicle(car2);
 
-    rental.print();
+    System.out.println(rental.toString());
   }
 }

Rental.java

@@ -2,14 +2,22 @@
 
 public class Rental {
 
-  private String name;
-  private ArrayList<Vehicle> vehicles;
+  private final String name;
+  private final ArrayList<Vehicle> vehicles;
 
   public Rental(String name) {
     this.name = name;
     vehicles = new ArrayList<>();
   }
 
+  public String getName() {
+    return name;
+  }
+
+  public ArrayList<Vehicle> getVehicles() {
+    return vehicles;
+  }
+
   public void addVehicle(Vehicle vehicle) {
     vehicles.add(vehicle);
   }
@@ -29,11 +37,11 @@ public void transformAllTrucks() {
     }
   }
 
-  public void print() {
-    System.out.println(name);
-    System.out.println("Unsere Fahrzeuge: ");
-    for (Vehicle v : vehicles) {
-      v.print();
+  public String toString() {
+    String result = name + "\n" + "Unsere Fahrzeuge: \n";
+    for (Vehicle vehicle : vehicles) {
+      result += vehicle.toString() + "\n";
     }
+    return result;
   }
 }

Truck.java

@@ -1,6 +1,6 @@
 public final class Truck extends Vehicle {
 
-  private int cargo;
+  private final int cargo;
   private boolean isTransformed;
 
   public Truck(String make, String model, Engine engine, int cargo) {
@@ -18,17 +18,15 @@ public boolean isTransformed() {
 
   public void transform() {
     if (isTransformed) {
-      isTransformed = false;
       System.out.println(
           getMake() + " " + getModel() + " verwandelt sich in einen Lastwagen zurueck");
     } else {
-      isTransformed = true;
       System.out.println(getMake() + " " + getModel() + " verwandelt sich in einen Autobot");
     }
+    isTransformed = !isTransformed;
   }
 
-  public void print() {
-    System.out.println(
-        getMake() + " " + getModel() + " (" + getEngine().getDescription() + ", " + cargo + "t)");
+  public String toString() {
+    return getMake() + " " + getModel() + " (" + getEngine().getDescription() + ", " + cargo + "t)";
   }
 }

Vehicle.java

@@ -2,15 +2,15 @@ public abstract class Vehicle {
 
   private String make;
   private String model;
+  protected double speedInKmh;
   private Engine engine;
-  protected double speed;
   private static int numberOfVehicles;
 
   public Vehicle(String make, String model, Engine engine) {
     this.make = make;
     this.model = model;
+    Vehicle.numberOfVehicles++;
     this.engine = engine;
-    numberOfVehicles++;
   }
 
   public String getMake() {
@@ -25,19 +25,23 @@ public Engine getEngine() {
     return engine;
   }
 
-  public static int getNumberOfVehicles() {
-    return numberOfVehicles;
+  public double getSpeedInKmh() {
+    return speedInKmh;
   }
 
-  public final void accelerate(int value) {
-    speed += value;
-    System.out.println(make + " " + model + " beschleunigt auf " + speed + "km/h");
+  public final void accelerate(int valueInKmh) {
+    speedInKmh += valueInKmh;
+    System.out.println(toString() + " beschleunigt auf " + speedInKmh + "km/h");
   }
 
-  public final void brake(int value) {
-    speed -= value;
-    System.out.println(make + " " + model + " bremst auf " + speed + "km/h ab");
+  public final void brake(int valueInKmh) {
+    speedInKmh -= valueInKmh;
+    System.out.println(toString() + " bremst auf " + speedInKmh + "km/h ab");
   }
 
-  public abstract void print();
+  public abstract String toString();
+
+  public static int getNumberOfVehicles() {
+    return Vehicle.numberOfVehicles;
+  }
 }