Exception handling scenerio based question

Division program:
1){

        int a = 10;

        int b = 0;
        int result=0;
        try {
            result = a / b;
        }
        catch(ArithmeticException e)
        {
            System.out.println("Enter valid number");


        }
        System.out.println("Result: " +

        result);




        } 

}

2)Array index program
{

        int arr[] = {10, 20, 30, 40};

        try
        {
            System.out.println(arr[5]);

        }
        catch(ArrayIndexOutOfBoundsException a)
        {
            System.out.println(a.getMessage());
        }



        } 

}

String conversion program:
{
String s = "ABC";
int num=0;
try {
num = Integer.parseInt(s);
System.out.println(num);
}
catch(NumberFormatException n)
{
System.out.println(n.getMessage());

        }


        }

        }
NullpointerException:

{

    try {
        String name = null;

    System.out.println(name.length());

    }

    catch(NullPointerException n)
    {
        System.out.println(n.getMessage());
    }


    }

    }

File index program:
{

     {
         try {

         FileReader fr = new FileReader("test.txt");
         int data = fr.read();
         System.out.println(data);


         }
         catch(IOException e)
         {
             System.out.println(e.getMessage());
         }





         }


    }

    }

Class casting program:

{

public static void main(String[] args) {

Object obj = new Integer(10);

try {
String s = (String) obj;
System.out.println(s);
}
catch(ClassCastException e)
{
System.out.println(e.getMessage());
}

}
String index program:
{

public static void main(String[] args) {
    String str = "Java";

try {

    System.out.println(str.charAt(10));

}
catch(StringIndexOutOfBoundsException e)
{
System.out.println(e.getMessage());
}

}

negative array size:
{

    try {
    int size = -5;
    int arr[] = new int[size];
    }
    catch(NegativeArraySizeException E)
    {
        System.out.println(E.getMessage());
    }

    treeset program:

{

    TreeSet set = new TreeSet();

try {
set.add(10);

    set.add(30);

    set.add("hari");

    System.out.println(set);

}
catch(ClassCastException e)
{
System.out.println(e.getMessage());
}

}
}

treeset program
{

    TreeSet set = new TreeSet();
    try {
    set.add(20);

    set.add(40);

    set.add(null);
    }
    catch(NullPointerException e )
    {
        System.out.println(e.getMessage());
    }
    }
}



         }