Discuss the concept of parameters. What are parameters for? What is the difference between formal parameters and actual parameters? Give an example in Java code that illustrates formal parameters and actual parameters.
The application should use a text file to capture the whole vehicle accidents data structure. To do this, add two methods to your center class:
1. A method to save the content of the created Java structure into a text file.
2. A method to restore the saved content back into an appropriate Java data structure for next run time.
Java provides a facility to create your own Exceptions which are basically derived classes of Exception. Write a class that defines a duplicate exception. The duplicate exception will be thrown if accidents are duplicated in the accidents list.
Design and implement a separate testing class to test the designed classes and check if classes meet the requirements.