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If Exercises

Lec04- if exercises

Create a new class called IfExercises. Each part below will be contained in a method.

  1. Read in a month number from the user. Using an if construct, output the text for that month e.g. 1 is January etc.. Use constants and allow for entries which are out of range.
    a. Put the code into a method called ifMonth() and call it from main().
    b. Protect the if statement to cater for exceptions e.g. entering a letter instead of a number throws a InputMismatchException.

Enter month (1-12): 6
June

Enter month (1-12): 12
December

Enter month (1-12): 13
Entry is out of range: 13

Enter month (1-12): a
Exception! java.util.InputMismatchException...

  1. Read in two integers from the user into variables x and y. If either value is negative, display an error showing the values. If both x and y are greater than 0 determine which of the two is the larger.
    a. Cater for exceptions.
    b. Insert the code into a method called iflargerOfTwoNumbers() and call from main().

Enter first number : 8
Enter second number : 3
8 is > 3

Enter first number: 2
Enter second number: 5
5 is > 2

Enter first number: w
Exception caught
java.util.InputMismatchException...

  1. Read in a numeric mark (whole number) from the user. If mark is negative or greater than 100, flag an error showing the erroneous value. Determine the grade based on the following criteria: 70..100 is an A; 60..69 is a B; 50..59 is a C; 40..49 is a D; otherwise it’s a Fail.
    a. insert the code into a method called ifGrade() and call from main().
    b. Allow for Exceptions.

Enter mark : 97
A

Enter mark : 65
B

Enter mark : 55
C

Enter mark : 45
D

Enter mark : 35
Fail

Enter mark : 102
Error in input: 102. Valid values are 0..100

Enter mark : t
Exception caught
java.util.InputMismatchException...

  1. Get in a temperature from the user (whole number). The temperature is graded as follows:
    a. -10 to +2 is “Very Cold”
    b. 3 to 9 is “Cold”
    c. 10 to 14 is “Mild”
    d. 15 to 20 is “Warm”
    e. 21 to 27 is “Very Warm”
    f 28 to 31 is “Hot”
    g. If the temperature is outside these ranges, output “Extreme temperature”.

At all times, insert the temperature into your output message.
Insert the code into a method called temperature() and call from main().
Use constants and cater for Exceptions.

Enter temperature : -8
Very Cold

Enter temperature : 4
Cold

Enter temperature : 13
Mild

Enter temperature : 16
Warm

Enter temperature : 28
Hot

Enter temperature : 30
Hot

Enter temperature : 36
Extreme Temperature!

Enter temperature : k
Exception caught...

  1. Write a method called ifLargest() that takes in three whole numbers. Using the if construct (and no logical operators), determine the largest number entered. Assume unique numbers and cater for exceptions.

Enter first number : 2
Enter second number : 3
Enter third number : 4
Largest Number is 4

Enter first number : 2
Enter second number : v
Exception caught...
java.util.InputMismatchException...

  1. Write a method called ternaryOperator(). In the method, set a Boolean variable isHappy to true and using the ternary operator, set a String variable named mood to “I am Happy” or “I am Sad” depending on isHappy. Expand the method to take in two integers x and y. Using the ternary operator, determine which of the two is the smallest.

I'm Happy!
Enter x : 4
Enter y : 5
minVal == 4

IfExercises.java