The process of wrapping up the data and, the code acting on the data together is known as encapsulation. This is a protective mechanism where we hide the data of one class from (an object of) another.Since, variables hold the data of a class to encapsulate a class you need ... Read More

Inheritance is a relation between two classes where one class inherits the properties of the other class. This relation can be defined using the extends keyword as −public class A extends B{ }The class which inherits the properties is known as sub class or, child class and the class whose properties ... Read More

An interface in Java is similar to class but, it contains only abstract methods and fields which are final and static.Just like classes you can extend one interface from another using the extends keyword as shown below −interface ArithmeticCalculations{    public abstract int addition(int a, int b);    public abstract ... Read More

An interface in Java is a specification of method prototypes. Whenever you need to guide the programmer or, make a contract specifying how the methods and fields of a type should be you can define an interface.To create an object of this type you need to implement this interface, provide ... Read More

Yes, you can write an interface without any methods. These are known as marking interfaces or, tagging interfaces.A marker interface i.e. it does not contain any methods or fields by implementing these interfaces a class will exhibit a special behavior with respect to the interface implemented.ExampleConsider the following example, here ... Read More

A Remote interface is available in the java.rmi package it is a marking/tagging interface, it is used with remote method invocation(RMI).RMI is a mechanism that allows an object residing in one system (JVM) to access/invoke an object running on another JVM.To it is a marking interface, to mark an object ... Read More

The java.text package provides a class named SimpleDateFormat which is used to format and parse dates in required manner (local).Using the methods of this class you can parse String to Date or, format Date to String.Parsing String to DateYou can parse a given String to Date object using the parse() ... Read More

A method which does not have body is known as abstract method. It contains only method signature with a semi colon and, an abstract keyword before it.public abstract myMethod();To use an abstract method, you need to inherit it by extending its class and provide implementation to it.A class which contains ... Read More

Interface in Java is similar to class but, it contains only abstract methods and fields which are final and static.Private fields of an interfaceIf the fields of the interface are private, you cannot access them in the implementing class.If you try to declare the fields of an interface private, a ... Read More

No, we cannot implement one interface from another you can just extend it using the extends keyword as −interface ArithmeticCalculations{    public abstract int addition(int a, int b);    public abstract int subtraction(int a, int b); } interface MathCalculations implements ArithmeticCalculations{    public abstract double squareRoot(int a);    public abstract ... Read More