Exception Handling

Question 1

what is an exception?

Answer 1

an error which occurs during a normal flow of a program

Question 2

why is exceptions bad?

Answer 2

they cause disrupted and abnormally terminates program

Question 3

exception handling helps to … (4 points)

Answer 3

1- try to recover
2- retry operation
3- display meaningful error
4- terminating the whole program but in a better way

Question 4

we use what operations for exception handling

Answer 4

try-catch or try-catch-finally

Question 5

if i divide by zero what type of exception occurs

Answer 5

ArithmeticException

Question 6

if an array index is more than the size or equals to -1 which exception is used

Answer 6

ArrayIndexOutOfBoundsException

Question 7

types of exceptions

Answer 7

checked and unchecked

Question 8

checked exceptions are handled at (compile, runtime)?

Answer 8

compile time

Question 9

how to fix checked exceptions

Answer 9

try-catch, and extend a throwable class either directly or indirectly

Question 10

examples of checked exceptions

Answer 10

FileNotFoundException and PrinterException

Question 11

unchecked exceptions occurs where?

Answer 11

outside the program

Question 12

most of the time unchecked exception can be expected or recovered (t or f)

Answer 12

false, most of the time it cannot be expected or recovered from

Question 13

how to fix unchecked exceptions?

Answer 13

must extend RuntimeException class directly or indirectly

Question 14

examples for unchecked exceptions?

Answer 14

NullPointerException , ClassCastException

Question 15

printwriter pckage is

Answer 15

java.io

Question 16

if theres an exception that a file can’t be written into this exception is called?

Answer 16

IOException

Question 17

can we make multiple catches?

Answer 17

yes

Question 18

exceptions should be ordered from…

Answer 18

very special to very general

Question 19

exception class must be placed at…

Answer 19

the very end

Question 20

finally block executed …

Answer 20

regardless the exception is thrown or not

Question 21

printwriter must be closed, if not closed it…

Answer 21

reserves unwanted memory

Question 22

throwing an exception comes in two forms …

Answer 22

Java Exception, User Defined Exception

Question 23

to make a user defined exception class …

Answer 23

make a class exception that extends class (main java class) exception

public class numberexception extends exception

Question 24

To use a user defined class…

Answer 24

we use the keyword throws in the declaration and then throw an object of the exception class

public int add () throws numberexception{

throw new numberexception (values);
}