Exception handling mechanisms allow programs to detect and respond to runtime errors or exceptional circumstances. They work by finding the problem, informing that an error occurred, receiving error information, and taking corrective action. Exceptions are caused by errors and thrown by the Java interpreter. There are different types of exceptions like ArithmeticException or ArrayIndexOutOfBoundsException. Exceptions can be checked, which must be explicitly handled, or unchecked, which are not necessarily handled in code. Try/catch blocks are used to handle exceptions by trying code that could cause exceptions and catching specific exception types to process them. Programs can also throw their own custom exceptions.

1. Submitted by
S.Nandhini
II-MSC(CS&IT)
Nadar Saraswathi college of arts & science
Theni

2.  The purpose of exception handling mechanism
is to provide a means to detect and report an
"exceptional circumstance" so that appropriate
action can be taken.
 The mechanism suggests incorporation of a separate
error handling code that performs the following tasks:

3. 1. Find the problem (Hit the exception).
2. Inform that an error has occurred (Throw the
exception)
3. Receive the error information (Catch the
exception)
4. Take corrective actions (Handle the exception)

4.  An exception is a condition that is caused by
a run-time error in the program.
 When the Java interpreter encounters an
error such as dividing an integer by zero, it
creates an exception object and throws it(i.e.,
informs us that an error has occurred).

5. EXCEPTION TYPE CAUSE OF EXCEPTION
ArithmeticException Caused by math errors such as division by
zero
ArraylndexOutOfBoundsException Caused by bad array indexes
ArrayStoreException to store the wrong type of data in an array
FileNotFoundException Caused by an attempt to access a nonexistent
file
(Continued)
StringIndexOutOfBoundsException Caused when a program attempts to access a
nonexistent character position in a string
StackOverflowException Caused when the system runs out of stack
space
NumberFormatException Caused when a conversion between strings
and number fails

6. Exceptions in java can be categorized in two types
 Checked Exceptions
 Un checked Exceptions
Checked exceptions:Exceptions are explicitly handled in
the code itself with help of try-catch blocks.
 Checked Exception are extended from the
java.lang.Exception class

7. Unchecked Exceptions: Exception are not essentially
handled in the program code instead JVM handles such
exception
 Unchecked exceptions are extended from the
java.lang.RuntimeException class

8. ..........
..........
try
{
statement; // generates an exception
}
catch (Exception type e)
{ statement; // processes the exception
}
..........
..........
The try block can have one or more statements
that could generate an exception.

9. class Error3
{
public static void main (String args[ ] )
{
int a = 10; int b = 5; int c = 5; int x, y ;(Continued)
try
{
x = a I (b-c) ; // Exception here
}.
catch (ArithmeticException e)
{
System.out.println(“Division by zero");
}
y = a I (b+c) ;
System.out.println(u y = U + y);
}
}
output: Division by zero. y = 1

10.  There may be times when we would like to throw our own
exceptions.
 SYNTAX
Examples:
Throw new NumberFormatException ();
Throw new NumberFormatException();
 The use of a user-defined subclass of Throwable class.
 Note that Exception is a subclass of Throwable and therefore
MyException is a subclass of Throwable class.
Throw new throwabl’e subclass;

11. THANK YOU