Preliminaries
1) Create a project submission folder, in the form Lab#FirstNameLastName. For example, mine would be Lab3DavidLiu
2) Create an Eclipse Java Project.
3) Add a Java class named InputValidation to your project
Exercises
A special species of space slug needs help contacting one of their spies on Earth.
The spies were given a special passphrase that they need to verify with a Java program. You have been hired to make this spy verifying Java Program.
All input will be handled with InputDialogs. Output will variable use the console and message dialogs.
Legitimate human program Enter your word, completely legitimate human OK Cancel
Part 1) Basic Input Verification -
To start, make an input box like the one in the screenshot. Afterwards, we will make some verification checks on the inputPart 1) Basic Input Verification - 6 Points
(a) Verify that when the user hits cancel, null is returned with print statement
(b) Now that the null is verified, add a check for it. Using an if statement to test for a null value and, if there is a null value, display a JOptionPane message box informing the user the input was null. You may comment our print statement from (a) using // or /* */.
(c) Inside the null checking if statement from part b, include the statement System.exit(0); This statement ends the program execution if the input is null!
(d) Verify that clicking ok without putting any input into the input box returns the empty string. You should use the equals() method for strings to do this. Use an if statement like in part b.
(e) Combine the if statements from b and d using logical operators. The if statement should check to see if the input is empty or null, use a JOption message box to inform the user of improper input, and then exit using System.exit(0); Do not delete the code from parts b and d; just comment it out using // or /* */
Part 2) False Security -
Now that our input is valid, we need to lull a human user of our ‘legitimate application' into a false sense of space security (which is like normal security, but more space-y).
(a) Ask the user for a second word, using a second input box. This input should be validated as in Part 1
(b) Write an if statement to check the equality of the two inputs. If the two are equal, a message box should be displayed informing the user they are equal. Otherwise, the user should be told they are not equal.
Part 3) Space Slug Verification -
The final part of our program verifies whether the user is our spy or not.
(a) Two conditions must be true for the user to be a spy. The first input must exactly equal the string "Banana Bread". The second input must be ‘larger' alphabetically than the string "ostrich". Broken down, this means:
a. Use equals() to check the first string against Banana Bread
b. Use compareTo to check the second string against ostrich. This can be written
two ways - check the book or the slides
(b) If the check from part (a) succeeds, print out a message confirming the spy has been validated and that they will soon be debriefed.
(c) If the check from part (a) fails, instead make another if-else statement checking the first input against the second with compare to. Have it tell the user which input is larger of the two.
Legitimate human program Enter your word, completely legitimate human OK Cancel