Adding bonus parts.

src/main/java/org/model/ElectricCar.java

@@ -56,4 +56,16 @@ public class ElectricCar extends Car implements Chargeable {
                 chargeLevel += amount;
         }
     }
+
+    @Override
+    public void performService() {
+        super.performService();
+        System.out.println("Electric engine and oil checked");
+        this.chargeLevel = 100;
+    }
+
+    @Override
+    public boolean needsService(Vehicle v) {
+        return getMileage() > 10000;
+    }
 }

src/main/java/org/model/HybridCar.java

@@ -0,0 +1,71 @@
+package org.model;
+
+import org.behavior.Chargeable;
+import org.behavior.Refuelable;
+
+public class HybridCar extends Car implements Refuelable, Chargeable {
+
+    private double fuelLevel;
+    private String fuelType;
+    private int batteryCapacity;
+    private double chargeLevel;
+
+    public HybridCar(String brand, String model, int year, double mileage, int seats, double fuelLevel, String fuelType, int batteryCapacity, double chargeLevel) {
+
+        super(brand, model, year, mileage, seats);
+        this.fuelLevel = fuelLevel;
+        this.fuelType = fuelType;
+        this.batteryCapacity = batteryCapacity;
+        this.chargeLevel = chargeLevel;
+    }
+    @Override
+    public String getEnergyType() {
+        return "Hybrid (Gas + Gasoline)";
+    }
+
+    @Override
+    public void showDetails() {
+        super.showDetails();
+        System.out.println(" | fuel level: " + fuelLevel + " | charge level: " + chargeLevel);
+
+    }
+
+    @Override
+    public boolean needsService(Vehicle v) {
+        return v.getMileage() > 10000;
+    }
+
+    @Override
+    public void performService() {
+        System.out.println("Engine oil changed and battery system checked");
+
+        this.fuelLevel = 100;
+        this.chargeLevel = 100;
+    }
+
+
+    @Override
+    public void charge(double amount) {
+        if(amount < 0)
+            System.out.println("amount unacceptable");
+        else{
+            if (chargeLevel + amount > 100)
+                chargeLevel = 100;
+            else
+                chargeLevel += amount;
+        }
+    }
+
+    @Override
+    public void refuel(double amount) {
+        if(amount < 0)
+            System.out.println("amount unacceptable");
+        else{
+            if (fuelLevel + amount > 100)
+                fuelLevel = 100;
+            else
+                fuelLevel += amount;
+        }
+    }
+}
+