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EXCEPTION HANDLING
slide 2: CONTENT
Introduction
Types of Exception Handling
try block
catch block
finally block
throw vs throws
slide 3: INTRODUCTION
An exception is an abnormal condition which occurs
during the execution of a program. To handle the
Exception we use exception handling mechanism.
Exception handling helps to maintain the normal flow
of execution of an application.
slide 4: TYPES OF EXCEPTION
An exception that is checked at compile time is
known as checked Exceptions. Examples of
Checked Exception are IOException
SQLException ClassNotFoundException.
Checked Exception:
slide 5: TYPES OF EXCEPTION
An exception that is not checked at compile time is
known as an unchecked exception. Examples of
Unchecked Exception are ArithmeticException
NullPointerException NumberFormatException.
Unchecked Exception:
slide 6: TYPES OF EXCEPTION
Errors are irrecoverable.
Exa- VirtualMachineError
StackOverFlowError
OutOfMemoryError.
Error:
slide 7: TRY BLOCK
It must be followed either by finally block or
Catch block.
It must be used within a method.
Try block is used to wrap the code that may throw
an exception.
slide 8: CATCH BLOCK
A catch block can be used only after the try
block.
All the catch block must be ordered from subclass
exception to super class exception.
The catch block is used to handle the exception.
multiple catch block can be within a single try block.
slide 9: FINALLY BLOCK
We put the cleanup code into the finally
block like closing a file.
A finally block will not execute only when If the
program terminates through System.exit or If
causing a fatal error.
A finally block is executed always whether the
exception is handled or not.
slide 10: THROW VS THROWS
throws keyword is used to declare an exception. It
provides information to the programmer that there may
occur an exception so It is programmer’s responsibility
to provide exception handler so that the normal flow of
application can be maintained
throw keyword is used to explicitly throw an exception.
It is generally used to throw a custom exception User
defined exception. It is used within a method body.
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THANK YOU