Write about Exception Handling concept in Java with Example?

https://www.computersprofessor.com/2016/11/exception-exception-is-condition-that.html
Exception:
An exception
is a condition that is caused by a run –time error in the program. when the
java interpreted encounters an error such as dividing an integer by zero. It
creates an exception object is not caught is handled properly the interpreter
will displayed an error message is will terminate the program .If we want the
program to continue with the execution of the remaining code then we should
try to catch the exception object thrown by the error condition and then
display an appropriate message for taking corrective actions.
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 action (handle the exception)
The error
handling code basically consists of two segments. One to detect errors is to
throw exception and the other to catch exception and to take appropriate
action.
Syntax of Exception Handling code:
The basic
concept of exception handling are throwing an exception and catching it
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Java uses a
keyboard try to preface a block of code i.e; likely to causes an error
condition and “throw” an exception. A catch block defined by the keyboard
catch “catches” the exception “thrown” by the try block and handles it
appropriately. The catch block is added immediately.
-------
try
{
Statement; // generates an exception.
}
catch (Exception type)
{
Statement ; // process the exception
}
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The try block
can have one as more statement that could generate an exception. If anyone
statement generates an exception, The remaining statement in the block are
skipped and execution jumps to the catch. That is placed next to the try
block.
The catch
statement block too can have one or more statement that are necessary to
process the exception remembers that every try statement should be followed
by at least one catch statement.
The catch
statement works like a method definition. The catch statement is passing a
single parameter which is reference to the exception object thrown. If the
catch parameter matches with the type of exception object, then the exception
is caught and statement in the catch block will be executed otherwise .The
exception is not caught and the default exception handles will cause the
exception to terminates.
Ex: class
error 3
{
public static void main (String args[ ])
{
int a = 10;
int b=5 ;
int c=5 ;
int x,y ;
try
{
x=a / (b-c);
}
catch (ArithmeticException e)
{
System.out.println (“ Division by zero”) ;
}
y= a/(b+c);
System.out.println (“y= “+y);
}
}
OutPut: Division by zero
y=1.
Multiple Catch Statements:
It is possible
to have more than one catch statement in the catch block as illustrated below
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try
{
Statement ; // generates an
exception
}
catch (exception – type1 e)
{
Statement; // processes exception type 1
}
catch (exception –type2 e)
{
statement; // process exception
type 2
}
catch (exception- typeN e)
{
Statement ;
}
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Exception in a try block is generated the
Java treats the multiple catch statement like, classes in a switch statement.
The first statement whose parameter match with the exception object will be
executed and the remaining statement will be skipped.
Using Finally Statement :
Java supports
another statement known as finally statement that can be used to handle on
exception i.e, is not caught by any of the previous catch statements, finally
block can be used to handle any exception generated with in a try block . It
may be added immediately after the try block or after the catch block shown
as follows.
try try
{ {
----- -----
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} }
finally catch(----)
{
{
-----
-----
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-----
} }
catch(----)
{
-----
-----
}
finally
{
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}
When a finally
block is defined this guaranteed to executed, regardless of whether or not in
exception is thrown. As a result, we can use at to perform certain house.
Keeping operation such as using files and releasing system resources.
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