Roster Manipulation - Main

import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Scanner;

/**
 * This program performs the following functions:
 * - Will load student records from input.txt into their respective variables
 * - Will turn those variables into a Student Object
 * - Calculate their average % based on test scores
 * - Places the Student objects into an ArrayList representing the academic class.
 * - Lists the class with their % score and letter grade in the class.
 * - Remove the records matching ID 42P4 and 45A3
 * - Re-list the records with the removed students.
 * - Add the Student Record: 67T4     ClouseB     80     75     98
 * - Add the Student Record: 45P5     GarrisonJ   75     78     72
 * - Add the Student Record: 89P0     SingerA     85     95     99
 * - Calculate the grades of the students and sort the ArrayList from Highest to lowest based on % score
 * - Print the ArrayList.
 *
 * @author Carlos
 * @since 01/25/2019
 **/
public class RosterManipulations {

    public static void main(String[] args) throws Exception {
        RosterManipulations me = new RosterManipulations();
        ArrayList<Student> AcademicClass=new ArrayList<Student>();

        try {
            Scanner input = new Scanner(new File("src/main/input.txt"));

            //Gather the information from the records in input.txt and set them equal to their respective variables
            while(input.hasNextLine()){
                String StudentID =input.next();
                String Studentname =input.next();
                int test1 =input.nextInt();
                int test2 =input.nextInt();
                int test3 =input.nextInt();
                int totalHours = input.nextInt();
                float oldGPA = input.nextFloat();

                //Place those variables into a student object
                Student student1 = me.new Student(StudentID, Studentname, test1, test2, test3, totalHours, oldGPA);


                //Place the student object into an array list
                me.AddStudent(AcademicClass,StudentID,Studentname,test1,test2,test3, totalHours, oldGPA);

            }

            System.out.println("\nOriginal Class Roster Before Modifications: \n");
            //Print the contents of the ArrayList including their % score and grade before any manipulation
            for(int i=0; i<AcademicClass.size(); i++){
                System.out.println(AcademicClass.get(i));
            }

            DeleteStudent(AcademicClass,"45A3");
            DeleteStudent(AcademicClass,"42P4");
            System.out.println("\nStudents 45A3 & 42P4 Have Dropped The Class. Generating New Roster: \n");
            //Print the contents of the ArrayList including their % score and grade AFTER the students have dropped
            for(int i=0; i<AcademicClass.size(); i++) {
                System.out.println(AcademicClass.get(i));
            }

            System.out.println("\n New Students Have Joined The Class. Generating Roster: \n");

            Scanner secondInput = new Scanner(new File("src/main/Additions.txt"));
            while(secondInput.hasNextLine()){
                String AddedID = secondInput.next();
                String AddedName = secondInput.next();
                int AddedTest1 = secondInput.nextInt();
                int AddedTest2 = secondInput.nextInt();
                int AddedTest3 = secondInput.nextInt();
                int AddedTotalHours = secondInput.nextInt();
                float AddedoldGPA = secondInput.nextFloat();

                Student student2 =me.new Student(AddedID,AddedName,AddedTest1,AddedTest2,AddedTest3, AddedTotalHours, AddedoldGPA);

                //Adding students the expected students to the Class
                me.AddStudent(AcademicClass,AddedID,AddedName,AddedTest1,AddedTest2,AddedTest3, AddedTotalHours, AddedoldGPA); }


            //Reprint the array with the students now added

            for(int i=0; i<AcademicClass.size(); i++){
                System.out.println(AcademicClass.get(i));
            }

            SortLarge(AcademicClass);
            System.out.println("\nRegenerating Roster Sorted By Average Grade\n");
            //print the contents of the array sorted by Larger to Smaller based on average %
            for(int i=0; i<AcademicClass.size(); i++){
                System.out.println(AcademicClass.get(i));
            }




        } catch (FileNotFoundException e) {
            System.err.println("File Input.txt was not found");
        }

    }
    //Sort the array from large to small based on test average
    public static void SortLarge(ArrayList<Student>AcademicClass){
        Student xsave;
        int isw = 1;
        while (isw == 1) {
            isw = 0;
            for (int i = 0; i < AcademicClass.size()-1; i++) {
                switch (AcademicClass.get(i).compareTo(AcademicClass.get(i + 1))) {
                    case 1://the objects in array x are in the right order
                        break;
                    case -1://objects out of order, they must be changed.
                        // This is where to the place holder is used to swap values
                        xsave = AcademicClass.get(i);
                        AcademicClass.set(i, AcademicClass.get(i+1));
                        AcademicClass.set(i + 1,xsave);
                        isw = 1;
                        break;
                    default://objects are equal no change
                }
            }
        }

    }

    //Adds a Student who has joined the class to the ArrayList
    public void AddStudent(ArrayList<Student>AcademicClass, String ID, String Name, int T1, int T2, int T3, int tHours, float oldGPA){
        Student newKid = new Student(ID, Name, T1, T2, T3, tHours, oldGPA);
        AcademicClass.add(newKid);
    }


    //Deletes a Student who has dropped the class from the array list.
    public static void DeleteStudent(ArrayList<Student>AcademicClass, String ID){
        for(int i=0; i<AcademicClass.size();i++){
            if(AcademicClass.get(i).getStudentID().equals(ID)){
                AcademicClass.remove(i);
            }
        }


    }


    //The Student class turns student records into objects ao that they an be sorted into an ArrayLIst
    public class Student implements Comparable <Student>{
        String StudentID;
        String Studentname;
        int test1;
        int test2;
        int test3;
        int average;
        int totalHours;
        float oldGPA;

        @Override
        //toString so that objects can be printed.
        public String toString() {
            return  " ID: "+ StudentID+" Name: "+Studentname+"\n Test 1 Score: "+test1+"\n Test 2 Score: " +test2+"\n Test 3 Score: "+ test3+ "\n Test Average: "+average+"%"+"\n Class Grade: "+averageGrade(average)+"\n Total Hours: "+totalHours+"\n GPA: "+calculatenewGPA(oldGPA,gradePoint(average),totalHours)+"\n Year Rank: "+yearRank(totalHours)+"\n";
        }
        //Calculates the NEW GPA of a student
        public float calculatenewGPA(float oldGPA, int gradePoint, int totalHours){
            return ((oldGPA*totalHours)+(2)*gradePoint)/(totalHours+2);
        }

        //Calculate the GradePoint Value of A GPA
        public int gradePoint(int average){
            {
                int gradePoint=0;
                if(average >= 90){
                    gradePoint = 4;
                }
                else if (average>= 80){
                    gradePoint = 3;
                }
                else if(average >= 70){
                    gradePoint = 2;
                }
                else if(average >= 60){
                    gradePoint = 1;
                }
                else if(average >= 0){
                    gradePoint = 0;
                }
                return gradePoint;
            }
        }

        //Calculate the Year Rank of each student
        public String yearRank(int totalHours){
            String rank=null;
            if(totalHours <= 30){
                rank = "Freshman";
            }
            else if (totalHours <= 60){
                rank = "Sophomore";
            }
            else if (totalHours <= 90){
                rank = "Junior";
            }
            else if (totalHours >= 91){
                rank ="Senior";
            }
            return rank;
        }

        //Turn the average into a letter grade
        public String averageGrade(int average){
            String averageLetter=null;
            if(average >= 90){
                averageLetter = "A";
            }
            else if (average>= 80){
                averageLetter = "B";
            }
            else if(average >= 70){
                averageLetter = "C";
            }
            else if(average >= 60){
                averageLetter = "D";
            }
            else if(average >= 0){
                averageLetter ="F";
            }
            return averageLetter;
        }

        //Calculate the average grade of a student


        //Constructor for Student Class
        public Student(String StudentID, String Studentname, int test1, int test2, int test3, int totalHours, float oldGPA){
            setStudentID(StudentID);
            setStudentname(Studentname);
            setTest1(test1);
            setTest2(test2);
            setTest3(test3);
            int average=(test1+test2+test3)/3;
            setAverage(average);
            setTotalHours(totalHours);
            setoldGPA(oldGPA);

        }

        //Setters for the Student Class
        public void setStudentID(String StudentID){
            this.StudentID = StudentID;
        }
        public void setStudentname(String Studentname){
            this.Studentname = Studentname;
        }
        public void setTest1(int test1){
            this.test1 = test1;
        }
        public void setTest2(int test2){
            this.test2 = test2;
        }
        public void setTest3(int test3){
            this.test3 = test3;
        }
        public void setAverage(int average){
            this.average = average;
        }
        public void setTotalHours(int totalHours){this.totalHours = totalHours;}
        public void setoldGPA(float oldGPA){this.oldGPA = oldGPA;}


        //Getters for the Student Class
        public String getStudentID(){
            return StudentID;
        }
        public String getStudentname(){
            return Studentname;
        }
        public int getTest1(){
            return test1;
        }
        public int getTest2(){
            return test2;
        }
        public int getTest3(){
            return test3;
        }
        public int getAverage(){return average; }
        public int getTotalHours(){return totalHours;}
        public float getoldGPA(){return oldGPA;}


        public int compareTo(Student o) {
            return (this.getAverage() < o.getAverage() ? -1 :
                    (this.getAverage() ==o.getAverage() ? 0 : 1));
        }
    }
}