public interface TaxCalculator double calculateTax(double income);
public abstract double calculateSalary(); Infosys Java Training Material Pdf
Four Pillars | Pillar | Java Implementation | |--------|---------------------| | Encapsulation | private fields + public getters/setters | | Inheritance | extends keyword | | Polymorphism | Method overloading & overriding | | Abstraction | abstract class / interface | Example: Encapsulation + Inheritance // Base class public abstract class Employee private String empId; private String name; public Employee(String empId, String name) this.empId = empId; this.name = name; public abstract double calculateSalary()