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9              {
                10                  System.out.println("Enter 2 numbers  : ");

                11                  a=sc.nextInt();

                12                  b=sc.nextInt();
                13                  s=a+b;
                14                  System.out.println("The result is : "+s);

                15              }
                16              catch(Exception ex)
                17              {

                18                  System.out.println("You are supposed to enter an integer value");

                19              }
                20          }
                21      }

              The output of the preceding program is as follows: (If taken a double value)















                            Let’s Revisit

                    ♦ The concepts of class and object are obtained by programs written using object-oriented programming languages such as
                   Java, C++, etc.
                    ♦ An object is a unique entity that contains properties, methods and events in an object-oriented programming language.
                    ♦ Classes in Java are non-primitive data types that act as a blueprint for creating objects of the same type.
                    ♦ The occurrence of a class that contains characteristics and behaviour of the same class is called an object. In other words,
                   objects are the instances of a class.
                    ♦ A user-defined data type is a derived data type depending on some existing data types.
                    ♦ A Virtual Machine (VM) uses software instead of a physical computer to execute programs and install apps.
                    ♦ During the execution of a program, an error may occur which may stop the execution of the program. This error is known as an
                   exception.
                    ♦ Exception handling is a mechanism to handle errors that occur during the execution of the program so that the normal flow of
                   the code can be maintained.
                    ♦ A “finally” keyword follows after the try block. It always executes whether there is an exception or not. It appears at the end of
                   the catch block.
                    ♦ Input/Output exceptions (I/O) are Java IOExceptions that occur whenever an input or output operation is unsuccessful or
                   interpreted.



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