complete Vehicle class

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

@@ -20,13 +20,36 @@ 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)
+        {
+            throw new IllegalArgumentException("Mileage cannot be negative!");
+        }
+        else
+        {
+            mileage += km;
+        }
+    }
 
-    // TODO: Declare abstract method getEnergyType()
+    public abstract String getEnergyType();
 
     public void basicInfo() {
         System.out.println(