Youtor
61 Java Tutorial Inheritance
>> YOUR LINK HERE: ___ http://youtube.com/watch?v=_9R_in_7cT4
Check out our courses: • Java Full Stack and Spring AI - https://go.telusko.com/JavaSpringAI • Coupon: TELUSKO10 (10% Discount) • DevOps with AWS: From Basics to Mastery : https://go.telusko.com/DevOpsAWS • Coupon: TELUSKO10 (10% Discount) • Master Java Spring Development : https://go.telusko.com/masterjava • Coupon: TELUSKO20 (20% Discount) • Udemy Courses: • Spring: https://go.telusko.com/udemyteluskosp... • Java:- https://go.telusko.com/udemyteluskojava • Java Spring:- https://go.telusko.com/Udemyjavaspring • Java For Programmers:- https://go.telusko.com/javaProgrammers • Python : https://go.telusko.com/udemyteluskopy... • Git : https://go.telusko.com/udemyteluskogit • Docker : https://go.telusko.com/udemyteluskodo... • For More Queries WhatsApp or Call on : +919008963671 • website : https://courses.telusko.com/ • In this lecture we are discussing : • 1)What is inheritance? • 2)With example and scenario we understand what is inheritance? • 3)Multilevel inheritance • 4)Type of relationship • #1 • In OOPs inheritance is a process of inheriting the properties of one class to another class. • e.g suppose a class has some property and behaviour and want this behaviour and properties to new class with additional property • we are using inheritance to inherit the property of one class to another. • #2 • Scenario based example • Suppose we hire a developer and want to made Calculator which can add • two number. • Step 1: • Developer A - created Calc class which has add method and provide .class file to me but not provide source code file. • class Calc { • public void add(int num1,int num2){ • System.out.println(num1+num2); • } • } • Now i removed that developer from his post and hire new developer but we want to add subtraction functionality to Calculator. • But problem is that if we have Calc class source file then we said to developer B to add subtraction method. • Step 2: • When we have source code file • then, • class CalcAdv{ • public void add(int num1,int num2){ • System.out.println(num1+num2); • } • public void sub(int num1,int num2){ • System.out.println(num1-num2); • } • } • But developer A does not provide Calc source code we have only Calc .class file. • Now we have one concept of OOPs that can help the developer B. • Step 3: • Now we have concept of inheritance in OOPs • lets us use extending or inheriting method from Calc class. • //inheriting add method from calc • class CalcAdv extends Calc{ • public void sub(int num1,int num2){ • System.out.println(num1-num2); • } • } • • class Main{ • public static void main(String []args){ • CalcAdv obj=new CalcAdv(); • obj.add(5,4); • obj.sub(5,4); //now we can use addition and subtraction functionality • } • } • :- This is know as single level inheritance • #3 • Multilevel inheritance • class Calc{ • public void add(int num1,int num2){ • System.out.println(num1+num2); • } • } • class CalcAdv extends Calc{ • public void sub(int num1,int num2){ • System.out.println(num1-num2); • } • //Now we can use the property and methods of Calc also • //Single level inheritence • } • class CalcSuperAdv extends CalcAdv{ • public void mul(int num1,int num2){ • System.out.println(num1*num2); • //But here you can use the property and methods of Calc as well as CalcAdv class • //multilevel inheritance we consider Calc, CalcAdv and CalcSuperAdv • } • } • Note:i) Multilevel inheritance allowed in java but Multiple inheritance not allowed in java we shall understand why this not allowed in next lecture • ii)Term- {super, parent, base}-- same meaning and {sub, child, derived}--same meaning • #4 • Type of relationship • i)IS-A relationship means one class is a child of another class. • e.g • class Animal{ • } • class Lion extends Animal{ • //here we found Lion is a animal • } • ii)HAS-A relationship means one class has using property and method of other class but that class is not a parent of current class. • class Bank{ • void withdrawMoney(){ • System.out.println( withdrawl); • } • } • class Hospital{ • A obj=new A(); • void accessMoney{ • obj.withdrawMoney(); • } • //here we can see a hospital has a bank access • } • • Instagram : / navinreddyofficial • Linkedin : / navinreddy20 • Discord : / discord • More Learning : • Java - https://bit.ly/3xleOA2 • Python :- https://bit.ly/3H0DYHx • Django :- https://bit.ly/3awMaD8 • Spring Boot :- https://bit.ly/3aucCgB • Spring Framework :- https://bit.ly/3GRfxwe • Servlet JSP :- https://bit.ly/3mh5CGz • Hibernate Tutorial :- https://bit.ly/3NWAKah • Rest API | Web Service Tutorial :- https://bit.ly/38RJCiy • Git :- https://bit.ly/3NUHB3V • JavaScript :- https://bit.ly/3mkcFys • Kotlin :- https://bit.ly/3GR2DOG • • Donation: • PayPal Id : navinreddy20 • Patreon : navinreddy20 • http://www.telusko.com/contactus
#############################
