What is difference between implement and extend in Java?
Difference: implements means you are using the elements of a Java Interface in your class. extends means that you are creating a subclass of the base class you are extending. You can only extend one class in your child class, but you can implement as many interfaces as you would like.
What does Extends mean in Java?
The extends keyword in Java indicates that the child class inherits or acquires all the properties of the parent class. This keyword basically establishes a relationship of an inheritance among classes.
What does it mean to implement an interface?
An Interface is a specification of functionality that a class MUST implement. When you implement an interface, you are specifying to any consumers of your class that you supply the functionality defined in the given Interface.
Is False a keyword in Java?
Here is a list of keywords in the Java programming language. … true , false , and null might seem like keywords, but they are actually literals; you cannot use them as identifiers in your programs.
What is super () in Java?
The super keyword in Java is a reference variable which is used to refer immediate parent class object. Whenever you create the instance of subclass, an instance of parent class is created implicitly which is referred by super reference variable. … super() can be used to invoke immediate parent class constructor.
Is overriding possible in Java?
In Java, methods are virtual by default. We can have multilevel method-overriding. Overriding vs Overloading : … Overriding is about same method, same signature but different classes connected through inheritance.
Why do we need package in Java?
Packages are used in Java in order to prevent naming conflicts, to control access, to make searching/locating and usage of classes, interfaces, enumerations and annotations easier, etc.
What is the purpose of interfaces?
The purpose of interfaces is to allow the computer to enforce these properties and to know that an object of TYPE T (whatever the interface is ) must have functions called X,Y,Z, etc.
Why do we implement interface?
Why do we use interface ? It is used to achieve total abstraction. Since java does not support multiple inheritance in case of class, but by using interface it can achieve multiple inheritance . It is also used to achieve loose coupling.
WHAT IS interface and its use?
You use an interface to define a protocol of behavior that can be implemented by any class anywhere in the class hierarchy. Interfaces are useful for the following: Capturing similarities among unrelated classes without artificially forcing a class relationship.