This document discusses exception handling in Java programs. It defines exceptions as events that disrupt normal program flow when errors occur. When an error happens within a method, the method creates an exception object and passes it to the runtime system. The runtime system then attempts to find exception handling code to catch and handle the exception. Exception handling code consists of throwing exceptions when errors are detected and catching exceptions to take appropriate actions. An example program demonstrates trying to parse user input as integers within a try-catch block to handle potential number format exceptions.

1. Exception Handling
Unit -III

2. Errors and Exceptions
Errors are the wrongs that makes a program go
wrong. Errors may be broadly classified into two
categories:
Compile time Errors (Syntax Errors)
Runtime Errors (Program may terminated when
we run the program)example:Dividing by Zero,
Stack overflow, file not found, array out of bound.

3. Exception
An exception is an event, which occurs during the
execution of a program, that disrupts the normal
flow of the program's instructions.
When an error occurs within a method, the method
creates an object and hands it off to the runtime
system.

4. The object, called an exception object, contains
information about the error, including its type and
the state of the program when the error occurred.
 Creating an exception object and handing it to
the runtime system is called throwing an
exception
After a method throws an exception, the runtime
system attempts to find something (code) to
handle it.
This block of code is called an exception handler.

5. • The Exception Handling code basically consist
of two segments:
To detect the exception and throw the
exception.
To catch exceptions and take appropriate
actions.

6. class CLInput
{
public static void main(String args[])
{
int invalid=0;
int count=0;
int number;
for(int i=0;i<args.length;i++)
{
try
{
number=Integer.parseInt(args[i]);
}
catch(NumberFormatException e)
{
invalid=invalid+1;
System.out.println("Invalid Number:"+args[i]);
continue;
}
count=count+1;
}
System.out.println("Number of Invalid Numvers:"+invalid);
System.out.println("Number of Valid Numvers:"+count);
}
}