Check out example codes for "multilevel inheritance in java". It will help you in understanding the concepts better.

Code Example 1

class Car{
   public Car()
   {
	System.out.println("Class Car");
   }
   public void vehicleType()
   {
	System.out.println("Vehicle Type: Car");
   }
}
class Maruti extends Car{
   public Maruti()
   {
	System.out.println("Class Maruti");
   }
   public void brand()
   {
	System.out.println("Brand: Maruti");
   }
   public void speed()
   {
	System.out.println("Max: 90Kmph");
   }
}
public class Maruti800 extends Maruti{

   public Maruti800()
   {
	System.out.println("Maruti Model: 800");
   }
   public void speed()
   {
	System.out.println("Max: 80Kmph");
   }
   public static void main(String args[])
   {
	 Maruti800 obj=new Maruti800();
	 obj.vehicleType();
	 obj.brand();
	 obj.speed();
   }
}

Code Example 2

class Car{
   public Car()
   {
	System.out.println("Class Car");
   }
   public void vehicleType()
   {
	System.out.println("Vehicle Type: Car");
   }
}
class Maruti extends Car{
   public Maruti()
   {
	System.out.println("Class Maruti");
   }
   public void brand()
   {
	System.out.println("Brand: Maruti");
   }
   public void speed()
   {
	System.out.println("Max: 90Kmph");
   }
}
class Maruti800 extends Maruti{

   public Maruti800()
   {
	System.out.println("Maruti Model: 800");
   }
   public void speed()
   {
	System.out.println("Max: 80Kmph");
   }
   public static void main(String args[])
   {
	 Maruti800 obj=new Maruti800();
	 obj.vehicleType();
	 obj.brand();
	 obj.speed();
   }
}

Code Example 3

Class X
{
   public void methodX()
   {
     System.out.println("Class X method");
   }
}
Class Y extends X
{
public void methodY()
{
System.out.println("class Y method");
}
}
Class Z extends Y
{
   public void methodZ()
   {
     System.out.println("class Z method");
   }
   public static void main(String args[])
   {
     Z obj = new Z();
     obj.methodX(); //calling grand parent class method
     obj.methodY(); //calling parent class method
     obj.methodZ(); //calling local method
  }
}

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