Eli CSC 201 Unit 5 Programming Problems Worksheet 392775

Eli Csc 201unit 5 Programming Problems Worksheetprogramming Problem 1

Revisit the Cycle class in Module 3. Modify your application such that the properties, numberOfWheels and weight are entered as double values interactively (at the keyboard). Exception handling will be used to determine whether a type mismatch occurs. Edit your application such that, in addition to the existing input validation, the values for numberOfWheels and weight entered interactively will throw a new exception “Values cannot be less than or equal to zero” only if the values are less than or equal to zero. Add or use the appropriate try and/or catch blocks.

Directions Examine your application for the class called Cycle. · Add Try and Catch blocks appropriately. · Add the throw statement for the new exception. · Display an appropriate message if an exception occurs. · Display the properties of the object.

Paper For Above instruction

The task involves modifying an existing Java program that models a Cycle class, focusing on input validation, exception handling, and file input/output operations. This comprehensive task ensures robust data validation, effective exception management, and proper file handling techniques, essential for developing reliable Java applications.

Part 1: Enhancing Input Validation with Exception Handling

The initial goal is to modify the Cycle class application so that the properties, specifically numberOfWheels and weight, are entered interactively as double values. To achieve this, Scanner input will be used to capture user data. Error handling will be incorporated to detect any type mismatch—such as entering a non-numeric value—and respond appropriately. A try-catch block surrounding the input code will catch {@link InputMismatchException} and display a user-friendly error message, prompting re-entry of valid data.

Furthermore, an additional validation step will be implemented to ensure that neither numberOfWheels nor weight is less than or equal to zero. If such a case occurs, the program will throw a custom exception—possibly a {@link IllegalArgumentException}—with the message “Values cannot be less than or equal to zero.” This exception will be caught in the same or an adjacent catch block, and an appropriate message will be displayed to inform the user of the invalid input. This approach guarantees that the object properties are set only with valid, meaningful data.

Implementation details include properly placing throw statements within validation logic, wrapping input prompts and assignments within try-catch blocks, and demonstrating robustness through repeated prompts if invalid data is entered. After successful validation, the program will output the properties of the Cycle object using System.out.println or equivalent methods.

Part 2: Writing Properties to a Text File

Next, the program will be modified to output the properties of the Cycle object to a text file named Cycle.txt. This involves adding an {@link throws} clause in the main method, typically {@link IOException} or {@link FileNotFoundException}. A reference to a {@link java.io.File} object will be created for Cycle.txt. The program will check whether this file exists; if it does not, it will be created.

Using a {@link java.io.PrintWriter} or {@link BufferedWriter}, the program will write the variable values—such as the number of wheels, weight, and other relevant properties—to the file. After writing, the file will be properly closed to ensure data integrity. Run the program and verify the content by opening Cycle.txt with a text editor or word processor, confirming that data has been correctly written and formatted.

Part 3: Reading Properties from a Text File

The third modification involves reading the previously saved data from Cycle.txt. The main method will include a {@link throws} clause for handling {@link IOException}. A {@link java.io.File} reference for Cycle.txt will be created, and the program will check that the file indeed exists before attempting to read.

Using a {@link java.io.BufferedReader} or {@link Scanner} with file input, the program will read the property values stored in the file. These values will be parsed appropriately—using methods like {@link Double.parseDouble}—and assigned back to object properties. The program will then display the retrieved data on the screen for verification. The file will be closed after reading, and error handling will ensure that missing or malformed files are managed gracefully.

Conclusion

Implementing these modifications enhances the robustness and functionality of the Cycle application. Exception handling improves user input validation, preventing invalid data from corrupting object state. File input/output features demonstrate data persistence and retrieval, essential for real-world applications requiring data storage. By combining interactive input validation with file operations, the program will be well-structured, reliable, and capable of handling typical runtime errors gracefully.

References

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