The document contains code for a Throwing class that gets integer input from the user. It uses try/catch blocks to handle exceptions. In the first code block, it catches InputMismatchException and throws an IllegalArgumentException. In the second code block, it changes the catch block to catch IOException instead of IllegalArgumentException and changes the thrown exception accordingly. Both code blocks prompt the user for an integer, catch invalid input, and print an error message.

1. Throwing.java
import java.util.InputMismatchException;
import java.util.Scanner;
public class Throwing
{
public static void main(String[] args)
{
try{
int n = getInt();
System.out.println(n);
}
catch(IllegalArgumentException e){
System.out.println(e.getMessage());
}
}
public static int getInt()
{
// your code goes here
int n;
try{
Scanner scan = new Scanner(System.in);
System.out.println("Enter an integer: ");
n = scan.nextInt();
}
catch(InputMismatchException e){
throw new IllegalArgumentException("Invalid Input. Please enter an integer.");
}
return n;
}
}
Output:
Enter an integer:
s
Invalid Input. Please enter an integer.
Throwing.java

2. import java.io.IOException;
import java.util.InputMismatchException;
import java.util.Scanner;
public class Throwing
{
public static void main(String[] args)
{
try{
int n = getInt();
System.out.println(n);
}
catch(IOException e){
System.out.println(e.getMessage());
}
}
public static int getInt() throws IOException
{
// your code goes here
int n;
try{
Scanner scan = new Scanner(System.in);
System.out.println("Enter an integer: ");
n = scan.nextInt();
}
catch(InputMismatchException e){
throw new IOException("Invalid Input. Please enter an integer.");
}
return n;
}
}
Output:
Enter an integer:
d
Invalid Input. Please enter an integer.
Solution

3. Throwing.java
import java.util.InputMismatchException;
import java.util.Scanner;
public class Throwing
{
public static void main(String[] args)
{
try{
int n = getInt();
System.out.println(n);
}
catch(IllegalArgumentException e){
System.out.println(e.getMessage());
}
}
public static int getInt()
{
// your code goes here
int n;
try{
Scanner scan = new Scanner(System.in);
System.out.println("Enter an integer: ");
n = scan.nextInt();
}
catch(InputMismatchException e){
throw new IllegalArgumentException("Invalid Input. Please enter an integer.");
}
return n;
}
}
Output:
Enter an integer:
s
Invalid Input. Please enter an integer.
Throwing.java

4. import java.io.IOException;
import java.util.InputMismatchException;
import java.util.Scanner;
public class Throwing
{
public static void main(String[] args)
{
try{
int n = getInt();
System.out.println(n);
}
catch(IOException e){
System.out.println(e.getMessage());
}
}
public static int getInt() throws IOException
{
// your code goes here
int n;
try{
Scanner scan = new Scanner(System.in);
System.out.println("Enter an integer: ");
n = scan.nextInt();
}
catch(InputMismatchException e){
throw new IOException("Invalid Input. Please enter an integer.");
}
return n;
}
}
Output:
Enter an integer:
d
Invalid Input. Please enter an integer.