1. Exception Handling In
Java
By Priyanka zope

2. Content
1:Introduction.
2:Error and Error Handling.
3:Exception.
4:Type Of Exception.
5:Coding Exception.
6:Advantages

3. Error and Error Handling.
v
An Error is any unexpected result obtained from a program during execution.
v
Unhandled errors may manifest themselves as incorrect
results or behavior, or as abnormal program termination.
v
Errors should be handled by the programmer, to prevent
them from reaching the user.

4. Exception
Exception- a better error handling.
Exception – an error condition that can occur during the
course of a program
execution
Ø
In Java, exceptions are objects themselves
Exception handling is another form of control structure
(like ifs and switch statements)
Ø
When an error is encountered, the normal flow
of the program is stopped and the exception is
Handled.

5. Types Of Exception
I:Checked Exception
Checked at compile time.
II:Unchecked Exception
Checked at runtime.

6. Coding Exception
1: try…..catch block
2:finally
3: throw

7. Try…catch block
•
To process an exception when it occurs, the line that throws the exception is
executed within a try block.
• A try block is followed by one or more catch clauses, which
contain code to process an exception.
•
The catch statement is used for catching exceptions.
try
{
<try block>
}
catch ( <ExceptionClass> <name> )
{
<catch block>
}
catch ( <ExceptionClass> <name> )
{
<catch block>}

8. Finally clause
•
A try statement can have an optional clause designated by
the reserved word finally.
• If no exception is generated, the statements in the finally
clause are executed after the statements in the try block
complete.
try {
// statements that throw exceptions
} catch(<exception>) {
// do stuff
} finally {
– // code here runs whether or not catch runs
}

9. Throw
All methods use the throw statement to throw an exception.
The throw statement requires a single argument: a throwable object.
Throwable objects are instances of any subclass of the Throwable class. Here's
an example of a throw statement.

10. Problem
IllegalArgumentException: illegal
parameter value
Problem
public class BankAccount
{
public void withdraw(double amount)
{
if (amount > balance)
{
?????????
}
balance = balance - amount;
}
. . .}

11. Solution
public class BankAccount
{
public void withdraw(double amount)
{
if (amount > balance)
{
IllegalArgumentException exception
= new IllegalArgumentException("Amount
exceeds balance");
throw exception;
}
balance = balance - amount;
}
. . .
}

12. Advantages
1:Separating Error-Handling Code from "Regular" Code
2:Grouping and Differentiating Error Types
3:consistency
4:flexibility
5:simplicity