SE-0010 Introduction to Java
Lab 3: Interest Calculator with Error Handling

Outcomes

• Develop additional proficiency with the Java language
• Develop further proficiency using common Java classes, such as Math, SImpleDateFormat, DecimalFormat, etc.
• Program mathematical expressions and formulas using the Java Math package
• Use methods of the String class to manipulate String data
• Incorporate conditional control statements, such as if and while, into a Java program to affect program control flow.

For this assignment, you will modify the CD interest calculator you began last lab. You will implement selection and iteration statements (if...else and while) to handle certain cases of invalid user input, as well as the ability to re-run the program with different input values.

Your program will still consist of a single InterestCalculator class, with the same methods as before. For this assignment, make the following changes to the methods:

getInitialValue - modify this method so that it checks to make sure the initial value entered for the CD is not null, not blank, and that the value is greater than 0 and less than 100000. If a correct value is not entered, print an error message similar to the one shown below and repeat the input prompt until the user enters a valid value.

getInterestRate - modify this method so that it checks to make sure the value entered for the interest rate of the CD is not null, not blank, and the value is greater than 0 and less than 100. If a correct value is not entered, print an error message and repeat the input prompt until the user enters a valid value.

getInterval -  modify this method so that it checks to make sure the value entered for the interval is not null, not blank, and the value is greater than 0 and less than 10. If a correct value is not entered, print an error message and repeat the input prompt until the user enters a valid value.

computeCDValue - No changes

displayResults - No changes.

main method - Continue to print a JOptionPane-based welcome screen at the start of the program. After the main method displays the results, add instructions that prompt the user whether they want to re-run the calculations for a different set of inputs, as shown below. If the user response is negative or they press Cancel or the Close icon), the program should end.

Test your program and make certain that it works correctly; use the results shown above to verify your output.

Remember: This is an individual assignment. While you may discuss the concepts with your classmates, you must write your own program. You may not copy or borrow code from your classmates.

Lab Submission (due 8:00am, Wednesday following lab)

Be sure to keep a copy of your work, in case something gets lost.

Your grade will be based on the following criteria:

• Meeting requirements - that is, a working Java program..
• Technical quality of both your program. For the program, technical quality consists of formatting, commenting, and following coding style guidelines we discussed in lectures and the textbook.
• Spelling and grammar (in comments).
• Timeliness of submission as stated in the course policies.