Question

Consider the code below. Note that the catch statements in the code are not implemented, but you will not need those details. Assume filename is a String, x is an int, a is a double array and i is an int. Use the comments i1, i2, i3, e1, e2, e3, e4, e5 to answer the question (i for instruction, e for exception handler).
try {

BufferedReader infile = new BufferedReader(new FileReader(filename)); // i1
int x = Integer.parseInt(infile.readLine( )); // i2
a[++i] = (double) (1 / x); // i3 }
catch (FileNotFoundException ex) {...} // e1
catch (NumberFormatException ex) {...} // e2
catch (ArithmeticException ex) {...} // e3
catch (ArrayIndexOutOfBounds ex) {...} // e4
catch (IOException ex) {...} // e5

Answer 1

Missing Part of Question

An exception raised by the instruction in i3 would be caught by the catch statement labeled?

Answer:

e3 and e4.

Explanation:

The instruction tag i3 points to the following code segment

a[++i] = (double) (1 / x); // i3

The code segment above performs arithmetic operation (double)(1/x)

And then assigns the value of the arithmetic operations to an array element a[++I]

It's possible to have one or both of the following two exceptions.

1. Error in Arithmetic Operation

2. Index of Array out of bound

These are both represented in exception tags e3 and e4

catch (ArithmeticException ex) {...} // e3

catch (ArrayIndexOutOfBounds ex) {...} // e4

Exception e3 can arise when the program try to carry out invalid arithmetic operation.

For instance, 1/0 or 0/0.

This will lead to ArithmeticException to be thrown

Exception e4 can arise when the program tries to assign values to an index that's not in an array.

Say, the total index in a given array a is 5.

The index of this array is 0 to 4; i.e. a[0] to a[4]

The moment the program tries to assign values to array element other than the ones I listed above (e.g a[5]) ArrayIndexOutOfBounds exception will be thrown