Unit 3

 

Exercises 

1. Modify the StudentRecordManager class provided for Unit 1 project to take advantage of composition design.   For grading purposes, use the StudentRecordManager.java file provided to you, not the one with your own work. Do not fill in #ADD portions.
   You still need other provided files for this project i.e. Student class and the data folder.
   After modification, the StudentRecordManager class should look like this (red means private):
   
   • recList is a private instance data member now;
   • The constructor should just initialize recList with loadFromFile() result;
   • displayRecords() is a public instance method (not private, not static) now and doesn’t take any parameters as the data it needs is in instance data member recList;
   • size() should just report # of records as now users of this class don’t have access to the arraylist.
   • Do not touch loadFromFile().
     Put this main() directly in StudentRecordManager class. This project should compile and work the same as before (the given project portion in Unit 1). Include a screenshot of your program output in assignment report.
       public static void main(String[] args)
       {
         // path and file name of data file
        String fileName = "data/cs219.txt";
     
         StudentRecordManager roster = new StudentRecordManager(fileName);
     
         roster.displayRecords();  // display data in table format
     
         // simple statistics
         System.out.println("Number of students: " + roster.size());
      } // end main