do tasks and learn OOP concepts like Interfaces, Inheritance, Polymorphism, and Abstraction.

src/main/java/org/model/Vehicle.java

@@ -20,13 +20,20 @@ public abstract class Vehicle {
         this.mileage = mileage;
     }
 
-    // TODO: Create getters for all fields
+    public String getBrand() { return brand; }
+    public String getModel() { return model; }
+    public int getYear() { return year; }
+    public double getMileage() { return mileage; }
 
-    // TODO: Implement addMileage(double km)
-    // If km is negative → print error
-    // Otherwise increase mileage
+    public void addMileage(double km) {
+        if (km < 0) {
+            System.out.println("Error: mileage cannot be negative.");
+        } else {
+            mileage += km;
+        }
+    }
 
-    // TODO: Declare abstract method getEnergyType()
+    public abstract String getEnergyType();
 
     public void basicInfo() {
         System.out.println(