Jdbc Connction Steps with Examples

Posted by: Instanceofjava Posted date: March 22, 2015 / comment : 0


Example to connect to oracle database:

 Connecting to java application to oracle database.you have to follow 5 steps :
1.load the driver class,
2.create the connection object,
3.create the statement object
4.execute query Connect
5.Connection close

oracle database connectivity steps:

Driver class:The oracle database driver class is oracle.jdbc.driver.OracleDriver.

Connection URl:The oracle database connection URL is jdbc:oracle:thin:@localhost:1521:xe.
here jdbc is API,oracle is the database, thin is the driver,local host is server on which oracle is running,or we can use IP address,1521 is port number and
and XE is the Oracle service name.

User name:The oracle database default userName is system.

Password:Password is given by the user at the time of installing the oracle database. In this example, we are going to use system123 as the password.

import java.sql.*;
class ConnecttoOracle{
public static void main(String args[]){
try{
// load the driver class
Class.forName("oracle.jdbc.driver.OracleDriver");

//create  the connection object
Connection con=DriverManager.getConnection(
"jdbc:oracle:thin:@localhost:1521:xe","system","oracle");

// create the statement object
Statement stmt=con.createStatement();

// execute query
ResultSet rs=stmt.executeQuery("select * from emp");
while(rs.next())
System.out.println(rs.getInt(1)+"  "+rs.getString(2)+"  "+rs.getString(3));

// close the connection object
con.close();

}
catch(Exception e){
System.out.println(e);}

}
}


Example to connect to Mysql databaase:



Connecting to java application to mysql database.you have to follow 5 steps :
1.load the driver class,
2.create the connection object,
3.create the statement object
4.execute queryConnect
5.Connection close

Mysql database connectivity steps:

Driver class:The mysql database driver class is com.mysql.jdbc.Driver.

Connection URl:The mysql database connection URL is jdbc:mysql://localhost:3306/test.
here jdbc is API,mysql is database,local host is server on which mysql is running,or we can use IP address,3306 is port number and test is database name.
we can use any database name here.

Username:The mysql database default userName is root.

Password:Password is given by the user at the time of installing the mysql database. In this example, we are going to use root123 as the password.

import java.sql.*;
class ConnecttoMysql{
public static void main(String args[]){
try{
class.forName("com.mysql.jdbc.Driver");

Connection con=DriverManager.getConnection(
"jdbc:mysql://localhost:3306/database name","root","root123");

//here root is username and root123 is password

Statement stmt=con.createStatement();

ResultSet rs=stmt.executeQuery("select * from emp");

while(rs.next())
System.out.println(rs.getInt(1)+"  "+rs.getString(2)+"  "+rs.getString(3));

con.close();

}
catch(Exception e){
System.out.println(e);}

}
}  

Servlet example programs in eclipse

Posted by: Instanceofjava Posted date: March 15, 2015 / comment : 0 ,

1.Run eclipse.File -> new -> dynamic web project

Servlet Example in exclipse


2. Give project name : example MyFirstApp and click on next



Servlet Example in exclipse


3. Please check Generate web.xml deployment descriptor to auto generate web.xml file


Servlet Example in exclipse




interview Servlet Example in exclipse

4.click on finish. now project structure will be created.

Servlet Example program in exclipse

5.Go to webcontent and create a folder with name Jsp to place jsp files and create a index.jsp.


Servlet Example program in exclipse




Servlet Example program in exclipse


Servlet Example program in exclipse





Servlet Example program in exclipse


6. index.jsp will have an error because it is not having servlet jar. file so we need to include servler-apt.jar file.

Servlet Example program in exclipse


Servlet Example program in exclipse



Servlet Example program in exclipse



now its fine. modify index.jsp with one text box and submit button.


Servlet Example program in exclipse




  1. <%@ page language="java" contentType="text/html; charset=ISO-8859-1
  2.     pageEncoding="ISO-8859-1"%>
  3. <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org
  4. /TR/html4/loose.dtd">
  5. <html>
  6. <head>
  7. <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
  8.  
  9. <title>Login</title>
  10.  
  11. </head>
  12. <body>
  13.  
  14. <form action="/MyFirstApp/hello" method="post">
  15.  
  16.        Name:<input type="text" name="name" value="">
  17.         <input type="submit" name="name" value="submit">
  18.  
  19.  </form>
  20.  
  21. </body>
  22.  
  23. </html>


7. create a servlet


Servlet Example program in exclipse






Servlet Example program in exclipse


Servlet Example program in exclipse


  1. package com.instanceofjava;
  2.  
  3. import java.io.IOException;
  4. import javax.servlet.ServletException;
  5. import javax.servlet.http.HttpServlet;
  6. import javax.servlet.http.HttpServletRequest;
  7. import javax.servlet.http.HttpServletResponse;
  8.  
  9. public class Hello extends HttpServlet{
  10.  
  11.   private static final long serialVersionUID = 1L;
  12.  
  13. public void doPost(HttpServletRequest req, HttpServletResponse res) throws IOException,
  14. ServletException{
  15.  
  16.         String str= (String) req.getParameter("name");
  17.         req.setAttribute("name", str);
  18.  
  19.         req.getRequestDispatcher("/Jsp/welcome.jsp").forward(req, res);
  20.  
  21.     }
  22. }

8. create a welcome.jsp page.


Servlet Example program in exclipse


Servlet Example program in exclipse








  1. <%@ page language="java" contentType="text/html; charset=ISO-8859-1" 
  2. pageEncoding="ISO-8859-1"%>
  3. <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org
  4. /TR/html4/loose.dtd">
  5. <html>
  6. <head>
  7. <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
  8.  
  9. <title>welcome</title>
  10. </head>
  11.  
  12. <body>
  13.  
  14. <%
  15. String str=null;
  16.  
  17. try{
  18.  
  19.     str=(String)request.getAttribute("name");
  20.  
  21. }catch(Exception e){
  22.  
  23. }
  24.  
  25. %>
  26.  
  27. <p>Welcome: <%=str %></p>
  28.  
  29. </body>
  30.  
  31. </html>


8. go to we.xml and include our servlet




Servlet Example program in exclipse



  1. <?xml version="1.0" encoding="UTF-8"?>
  2. <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  3. xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns
  4. /javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  5.  <display-name>MyFirstApp</display-name>
  6.  <welcome-file-list>
  7.  
  8.     <welcome-file>/Jsp/index.jsp</welcome-file>
  9.  
  10.   </welcome-file-list>
  11.  
  12.   <servlet>  
  13.  
  14.    <servlet-name>HelloServlet</servlet-name>  
  15.    <servlet-class>com.instanceofjava.Hello</servlet-class> 
  16.  
  17.   </servlet>  
  18.  
  19. <servlet-mapping>
  20.  
  21.         <servlet-name>HelloServlet</servlet-name>
  22.         <url-pattern>/hello</url-pattern>
  23.     </servlet-mapping>
  24.  
  25. </web-app>


9. run the project , select tomcat 7 from apache.

Servlet Example program in exclipse


10. Enter your name and click on submit.

Servlet Example program in exclipse


Servlet Example program in exclipse


Accessibility modifiers examples

Posted by: Instanceofjava Posted date: March 09, 2015 / comment : 0


  • The keywords which define accessibility permissions are called accessibility modifiers.
  • Java supports four accessibility modifiers to define accessibility permissions at different levels.

Accessibility modifier keywords: 

 1.private

 2.protected

 3.public

 4.default(no keyword)

1.private:

  • The class members which have private keyword in its creation statement are called private members. Those members are only accessible within that class.
  • If we declare any variable or method with private accessibility modifier then those variables and methods are accessible only within that class , not accessible out side the class.

private variable are accessible within the class :


  1. package com.instanceofjava;
  2.  
  3. public class PrivateDemo {
  4.  
  5.     private String first_name;
  6.     private String last_name;
  7.  
  8. void show(){
  9.  
  10.   System.out.println("First Name:="+first_name);
  11.   System.out.println("Last Name:="+last_name);
  12.  
  13. }
  14.  
  15. public static void main(String[] args) {
  16.  
  17.        PrivateDemo obj= new PrivateDemo ();
  18.  
  19.         obj.first_name="James";
  20.         obj.last_name="Goosling";
  21.         obj.show();
  22.  
  23.     }
  24. }

Output:

  1. First Name:=James
  2. Last Name:=Goosling

private variable are not  accessible out side the class :

  1. package com.instanceofjava;
  2.  
  3. public class PrivateDemo {
  4.  
  5.     private String first_name;
  6.     private String last_name;
  7.  
  8. void show(){
  9.  
  10.   System.out.println("First Name:="+first_name);
  11.   System.out.println("Last Name:="+last_name);
  12.  
  13. }
  14.  
  15. public static void main(String[] args) {
  16.  
  17.        PrivateDemo obj= new PrivateDemo ();
  18.  
  19.         obj.first_name="James";
  20.         obj.last_name="Goosling";
  21.       
  22.  
  23.     }
  24. }

  1. package instanceofjava;
  2.  
  3. class Demo {
  4.  
  5. public static void main(String[] args){
  6.  
  7. PrivateDemo obj= new PrivateDemo ();
  8.  
  9.         obj.first_name="James"; // ERROR: The field PrivateDemo.first_name is not visible
  10.  }
  11.  
  12. }

private methods are accessible within the class :

  1. package com.instanceofjava;
  2.  
  3. public class PrivateDemo {
  4.  
  5.     private String first_name;
  6.     private String last_name;
  7.  
  8. private void show(){
  9.  
  10.   System.out.println("First Name:="+first_name);
  11.   System.out.println("Last Name:="+last_name);
  12.  
  13. }
  14.  
  15. public static void main(String[] args) {
  16.  
  17.        PrivateDemo obj= new PrivateDemo ();
  18.  
  19.         obj.first_name="James";
  20.         obj.last_name="Goosling";
  21.         obj.show();
  22.  
  23.     }
  24. }

Output:

  1. First Name:=James
  2. Last Name:=Goosling

private variable are not  accessible out side the class :

  1. package com.instanceofjava;
  2.  
  3. public class PrivateDemo {
  4.  
  5.     private String first_name;
  6.     private String last_name;
  7.  
  8. void show(){
  9.  
  10.   System.out.println("First Name:="+first_name);
  11.   System.out.println("Last Name:="+last_name);
  12.  
  13. }
  14.  
  15. public static void main(String[] args) {
  16.  
  17.        PrivateDemo obj= new PrivateDemo ();
  18.  
  19.         obj.first_name="James";
  20.         obj.last_name="Goosling";
  21.       
  22.  
  23.     }
  24. }

  1. package instanceofjava;
  2.  
  3. class Demo {
  4.  
  5. public static void main(String[] args){
  6.  
  7. PrivateDemo obj= new PrivateDemo ();
  8.  
  9.         obj.add(); // ERROR: The method add() from the type PrivateDemo is not visible
  10.  }
  11.  
  12. }



  • private variables and methods are accessible inside that class only. If we declare any variable or method as private , not accessible outside the class.

2.protected

  • The class members which have protected keyword in its creation statements are called protected members. Those members can be accessible with in package from all classes, but from out side package only in subclass that too using subclass name or its object.
  • protected variables accessible inside the package anywhere. Outside package accessible only in sub classes.

Same package anywhere:

  1. package com.instanceofjava;
  2.  
  3. public class ProtectedDemo {
  4.  
  5.     protected int a;
  6.     protected int b;
  7.  
  8. protected void show(){
  9.  
  10.   System.out.println("a="+a);
  11.   System.out.println("b="+b);
  12.  
  13. }
  14.  
  15. public static void main(String[] args) {
  16.  
  17.        ProtectedDemo obj= new ProtectedDemo ();
  18.  
  19.         obj.a=12;
  20.         obj.b=13;
  21.         obj.show();
  22.  
  23.     }
  24. }

Output:

  1. a=12
  2. b=13

Different package subclass:

  1. package com.accesiblitymodifiers;
  2.  
  3. public class Sample extends ProtectedDemo {
  4.  
  5. public static void main(String[] args) {
  6.  
  7.        Sample  obj= new Sample();
  8.  
  9.         obj.a=12;
  10.         obj.b=13;
  11.         obj.show();
  12.  
  13.     }
  14. }

Output:

  1. a=12
  2. b=13

3.public

  • If we declare any variable or method with public access specifier then those members will be accessible to everywhere.


  1. package com.instanceofjava;
  2.  
  3. public class PublicDemo {
  4.  
  5.     public int x;
  6.     public int y;
  7.  
  8. public void show(){
  9.  
  10.   System.out.println("x="+x);
  11.   System.out.println("y="+y);
  12.  
  13. }
  14.  
  15. public static void main(String[] args) {
  16.  
  17.        PublicDemo obj= new PublicDemo ();
  18.  
  19.         obj.x=1;
  20.         obj.y=2;
  21.         obj.show();
  22.  
  23.     }
  24. }


Output:

  1. x=1
  2. y=2

4.default

  • If we declare any member with no keyword those members are called default members.
  • default members are accessible to package level.
  • Means we can access anywhere in same package but we can not access in out side the package under any condition.
  • So default will acts as public inside package and private out side the package.

Java data types with examples

Posted by: Instanceofjava Posted date: March 09, 2015 / comment : 0


  1. Primitive data types or Fundamental data types.
  2. Referenced data types or Derived data types.



1.Primitive Data types


1.byte

  1. package com.instanceofjava;
  2.  
  3. public class ByteDemo {
  4.  
  5. public static void main(String[] args) {
  6.  
  7.         byte a=10; // a is a variable of type byte holding the value 1;
  8.         byte b=20;// b is a variable of type byte holding the value 2;
  9.         
  10.         byte c= (byte)(a+b);
  11.         System.out.println(c);
  12.  
  13.     }
  14. }

Output:

  1. 3

2.short

  1. package com.instanceofjava;
  2.  
  3. public class ShortDemo {
  4.  
  5. public static void main(String[] args) {
  6.  
  7.         short a=1;
  8.         short b=2;
  9.         
  10.         short c= (short)(a+b);
  11.         System.out.println(c);
  12.  
  13.     }
  14. }

Output:

  1. 3

3.int

  1. package com.instanceofjava;
  2.  
  3. public class IntDemo {
  4.  
  5. public static void main(String[] args) {
  6.  
  7.         int a=10; // a is a variable of type integer holding the value 10;
  8.         int b=20;// b is a variable of type integer holding the value 20;
  9.         
  10.         int c= a+b;
  11.         System.out.println(c);
  12.  
  13.     }
  14. }

Output:

  1. 30


4.long

  1. package com.instanceofjava;
  2.  
  3. public class LongDemo {
  4.  
  5. public static void main(String[] args) {
  6.  
  7.         long a=1234567890;
  8.         long b=1234567890;
  9.  
  10.         long c= a+b;
  11.  
  12.         System.out.println(c);
  13.  
  14.     }
  15. }

Output:

  1. 2469135780


5.float

  1. package com.instanceofjava;
  2.  
  3. public class FloatDemo {
  4.  
  5. public static void main(String[] args) {
  6.  
  7.         float a=1234567.8f;
  8.         float b=1234567.8f;
  9.  
  10.         float c= a+b;
  11.  
  12.         System.out.println(c);
  13.  
  14.     }
  15. }

Output:

  1. 2469135.5


7.double

  1. package com.instanceofjava;
  2.  
  3. public class DoubleDemo {
  4.  
  5. public static void main(String[] args) {
  6.  
  7.         double a=1234567910112181314151634444422233334491.1d;
  8.         double b=1234567910112181314151634444422233334491.8d;
  9.         double c= a+b;
  10.         System.out.println(c);
  11.  
  12.     }
  13. }

Output:

  1. 2.4691358202243627E39



8.char

  1. package com.instanceofjava;
  2.  
  3. public class CharDemo {
  4.  
  5. public static void main(String[] args) {
  6.  
  7.         char a='A';
  8.         char b= 'B';
  9.  
  10.       System.out.println(a);
  11.       System.out.println(b);
  12.       System.out.println(a+b);
  13.  
  14.     }
  15. }

Output:

  1. A
  2. B
  3. 131


9.boolean

  1. package com.instanceofjava;
  2.  
  3. public class BooleanDemo {
  4.  
  5. public static void main(String[] args) {
  6.  
  7.         boolean a=true;
  8.         boolean b= false;
  9.  
  10.       System.out.println(a);
  11.       System.out.println(b);
  12.   
  13.  
  14.     }
  15. }

Output:

  1. true
  2. false

1.Referenced Data types

1.class


  1. package com.instanceofjava;
  2.  
  3. public class Sample{
  4.  int a,b; 
  5.  
  6. void add(){
  7. System.out.println(a+b);
  8. }

  10. public static void main(String[] args) {
  11.  
  12.        Sample obj= new Sample();
  13.  
  14.        obj.a=10;
  15.        obj.b=12;

  17.        obj.add();
  18.  
  19.     }
  20. }

Output:

  1. 22

2.Array

  1. package com.instanceofjava;
  2.  
  3. public class ArrayDemo {
  4.  
  5. public static void main(String[] args) {
  6.  
  7.         int a[]={1,2,3,4,5,6};
  8.  
  9.         for (int i = 0; i < a.length; i++) {
  10.             System.out.println(a[i]);
  11.         }
  12.   
  13.  
  14.     }
  15. }

Output:

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6


Constructors in java

Posted by: Instanceofjava Posted date: March 08, 2015 / comment : 0





  • Constructors will be executed when the object is created.
  • Constructors should have same name of class name.
  • Executed once per object.
  • Basically used to assign instance variables
  • We can overload constructors.
  • We can call super class constructor form sub class constructor.






  1. package instanceofjava;
  2. class A{
  3. A(){
  4. }
  5. }
  6. }

  • while creating object constructor will be executed so we can assign instance variables to some default values.

  1. package instanceofjava;
  2. class A{
  3. int a,b
  4. A(int x, int y){
  5. a=x;
  6. b=y;
  7. }
  8.  
  9. public static void main(String[] args){
  10.  A a=new A(10,20);

  12. }
  13. }

Types of constructors:

  • There are two types of constructors 
  • Default constructors
  • Parameterized constructor.

Default constructor:

  •  Default constructor will not have any arguments.
  • If we not defined any constructor in our class. JVM automatically defines a default constructor to our class.
  1. package instanceofjava;
  2. class Sample{
  3. int a,b
  4. Sample(){
  5. a=37;
  6. b=46;
  7. }
  8.  
  9. public static void main(String[] args){
  10.  
  11.  Sample obj=new Sample();
  12.   System.out.println(obj.a);
  13.   System.out.println(obj.b);
  14.  
  15. }
  16. }

Output:

  1. 37
  2. 46

Parameterized constructor


  1. package instanceofjava;
  2. class Sample{
  3. int a,b
  4. Sample(int x, int y){
  5. a=x;
  6. b=y;
  7. }
  8.  
  9. public static void main(String[] args){
  10.  
  11.  Sample obj=new Sample(37,46);
  12.   System.out.println(obj.a);
  13.   System.out.println(obj.b);
  14.  
  15. }
  16. }

Output:

  1. 37
  2. 46

Constructor overloading:

  1. package instanceofjava;
  2. class Sample{
  3. int a,b 
  4. Sample(){
  5. this(1,2);
  6.  System.out.println("Default constructor");
  7.  
  8. }
  9. Sample(int x , int y){
  10.  
  11. this(1,2,3); 
  12. a=x;
  13. b=y;
  14.  System.out.println("Two argument constructor");
  15.  
  16. }
  17.  
  18. Sample(int a , int b,int c){
  19.  System.out.println("Three argument constructor")
  20. }
  21. public static void main(String[] args){
  22.  
  23.  Sample obj=new Sample();
  24.   System.out.println(obj.a);
  25.   System.out.println(obj.b);
  26.  
  27. }
  28. }


Output:

  1. Three argument constructor
  2. Two argument constructor
  3. Default argument constructor
  4. 1
  5. 2





This and Super Keywords

Posted by: Instanceofjava Posted date: March 08, 2015 / comment : 0


  • this keyword used to store current object reference.
  • super keyword used to store super class reference in subclass object.

this keyword:

  • Predefined instance variable to hold current object reference.

It must used explicitly if non-static variable and local variable name is same.

 

 





  1. package com.instanceofjava;
  2.  
  3. public class ThisDemo {
  4.     int a, b;
  5.  
  6.  ThisDemo(int a, int b){
  7.  
  8.         a=a;
  9.         b=b;
  10.  }
  11.  
  12.     public static void main(String[] args){
  13.  
  14.         ThisDemo obj= new ThisDemo(1,2);
  15.         
  16.         System.out.println(obj.a);
  17.         System.out.println(obj.b);
  18. }
  19. }

Output:

  1. 0
  2. 0
  • Without this keyword if variable names are same we can not assign instance variables so this problem will solve by using this keyword

  1. package com.instanceofjava;
  2.  
  3. public class ThisDemo {
  4.     int a, b;
  5.  
  6.  ThisDemo(int a, int b){
  7.  
  8.         this.a=a;
  9.        this.b=b;
  10.  }
  11.  
  12.     public static void main(String[] args){
  13.  
  14.         ThisDemo obj= new ThisDemo(1,2);
  15.         
  16.         System.out.println(obj.a);
  17.         System.out.println(obj.b);
  18. }
  19. }

Output:

  1. 1
  2. 2

Used to invoke current class constructor:

  1. package com.instanceofjava;
  2.  
  3. public class ThisDemo {
  4.     int a, b;
  5.  
  6. ThisDemo(){
  7. System.out.println("Default constructor called");
  8. }

  10.  ThisDemo(int a, int b){
  11.        this();
  12.         this.a=a;
  13.        this.b=b;
  14.  }
  15.  
  16.     public static void main(String[] args){
  17.  
  18.         ThisDemo obj= new ThisDemo(1,2);
  19.         
  20.         System.out.println(obj.a);
  21.         System.out.println(obj.b);
  22. }
  23. }

Output:

  1. Default constructor called
  2. 1
  3. 2

Used to call current class method:

 

  1. package com.instanceofjava;
  2.  
  3. public class Sample{
  4.     int a, b;
  5.  

  7.  Sample(int a, int b){
  8.       
  9.        this.a=a;
  10.        this.b=b;
  11.  }
  12.  
  13. void show(){
  14.  
  15. System.out.println("Show() method called");
  16.    
  17. }
  18.  
  19. void print(){
  20.  
  21.     this.show();
  22.     System.out.println(obj.a);
  23.     System.out.println(obj.b);
  24.  
  25.  }
  26.     public static void main(String[] args){
  27.  
  28.         Sample obj= new Sample(1,2);
  29.         
  30.       
  31.         obj.print()
  32. }
  33. }



Output:

  1. Show() method called
  2. 1
  3. 2

super keyword:

  • Predefined instance variable used to hold super class object reference through sub class object.

 

Used to call super class constructor:



  1. package com.instanceofjava;
  2.  
  3. public class A{
  4.     int a, b;
  5.  
  6.  A(int a, int b){
  7.  
  8.         a=a;
  9.         b=b;
  10. System.out.println("super class constructor called");
  11.  
  12.  }
  13.  
  14. }


  1. package com.instanceofjava;
  2.  
  3. public class B extends A{
  4.     int a, b;
  5.  
  6.  A(int a, int b){
  7.     super(a,b);
  8.         a=a;
  9.         b=b;
  10. }
  11. public static void main(String[] args){
  12.  
  13.         B obj= new B(1,2);
  14.         
  15.     
  16. }
  17.  
  18.  }
  19.  
  20. }

Output:

  1. super class constructor called
  2. 1
  3. 2

Used to call super class methods from subclass:


  1. package com.instanceofjava;
  2.  
  3. public class A{
  4.     int a, b;
  5.  
  6.  A(int a, int b){
  7.  
  8.         a=a;
  9.         b=b;
  10. System.out.println("super class constructor called");
  11.  
  12.  }
  13.  
  14. void add(){
  15. System.out.println("super class method called");
  16. }
  17.  
  18. }


  1. package com.instanceofjava;
  2.  
  3. public class B extends A{
  4.     int a, b;
  5.  
  6.  A(int a, int b){
  7.     super(a,b);
  8.         a=a;
  9.         b=b;
  10. }
  11. void print(){ 
  12. super.add();
  13. System.out.println(this.a);
  14. System.out.println(this.b);
  15.  


  18. }
  19. public static void main(String[] args){
  20.  
  21.         B obj= new B(1,2);
  22.         
  23.        obj.print();
  24. }
  25.  
  26.  }
  27.  
  28. }

Output:

  1. super class method called
  2. 1
  3. 2
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