What is Exceptional Handling in Java? and how it work?

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2. Roll No: CS-1317
BS-Computer Science
4th Semester
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3. Topic:
Exceptional Handling

4.  What is Exception?
 Definition of Exception Handling?
 Why this occur in program?
 Why we use Exception Handling?
 Its Benefits?
 Catching Exceptions.
 Syntax
 Example
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5.  Dictionary Meaning: Exception is an abnormal
condition.
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6.  Exception Handling is a mechanism to handle
runtime errors such as ClassNotFound, IO,
SQL, etc.
 An exception is a problem that arises during
the execution of a program.
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7.  A user has entered invalid data.
 A file that needs to be opened cannot be
found.
 Abnormal termination of program.
 Some exceptions occurs by physical resources
that have failed in some manner (system
dependent events).
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8.  Exception Handling normally use to avoid
disrupts (Break up) the normal flow of the
application that is why we use exception
handling.
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9.  The core advantage of exception handling is
to maintain the normal flow of the
application.
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10.  A method catches an exception using a
combination of the try and catch keywords.
 A try/catch block is placed around the code
that might generate an exception.
 Code within a try/catch block is referred to
as protected code.
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11. 1. try
2. {
3. //Protected code
4. }
5. catch(ExceptionName Object)
6. {
7. //Catch block
8. }
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12. The following is an array is declared with 2
elements. Then the code tries to access the 3rd
element of the array which throws an exception.
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13. 1. import java.io.*;
2. public class ExcepTest{
3. public static void main(String args[]){
4. try{
5. int a[] = new int[2];
6. System.out.println("Access element three :" +
a[3]);
7. }
8. catch(ArrayIndexOutOfBoundsException e)
9. {
10. System.out.println("Exception thrown :" + e);
11. }
12. System.out.println("Out of the block");
13. }
14. }
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14.  http://www.tutorialspoint.com/java/java_exceptions.htm
 http://www.javatpoint.com/exception-handling-in-java
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