Write a main java program to read course records from ProgramOfStudy.

Implement Iterable interface to display the course list and then remove all courses that dont have grade. Display the list after removing those records.

//////ProgramOfStudy//////////////

import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.io.Serializable; import java.util.Iterator; import java.util.LinkedList; import java.util.List;

/** * Represents a Program of Study, a list of courses taken and planned, for an * individual student. * */ public class ProgramOfStudy implements Iterable, Serializable { private List list; /** * Constructs an initially empty Program of Study. */ public ProgramOfStudy() { list = new LinkedList(); } /** * Adds the specified course to the end of the course list. * * @param course the course to add */ public void addCourse(Course course) { if (course != null) list.add(course); } /** * Finds and returns the course matching the specified prefix and number. * * @param prefix the prefix of the target course * @param number the number of the target course * @return the course, or null if not found */ public Course find(String prefix, int number) { for (Course course : list) if (prefix.equals(course.getPrefix()) && number == course.getNumber()) return course;

return null; } /** * Adds the specified course after the target course. Does nothing if * either course is null or if the target is not found. * * @param target the course after which the new course will be added * @param newCourse the course to add */ public void addCourseAfter(Course target, Course newCourse) { if (target == null || newCourse == null) return; int targetIndex = list.indexOf(target); if (targetIndex != -1) list.add(targetIndex + 1, newCourse); }

/** * Replaces the specified target course with the new course. Does nothing if * either course is null or if the target is not found. * * @param target the course to be replaced * @param newCourse the new course to add */ public void replace(Course target, Course newCourse) { if (target == null || newCourse == null) return; int targetIndex = list.indexOf(target); if (targetIndex != -1) list.set(targetIndex, newCourse); }

/** * Creates and returns a string representation of this Program of Study. * * @return a string representation of the Program of Study */ public String toString() { String result = ""; for (Course course : list) result += course + " "; return result; } /** * Returns an iterator for this Program of Study. * * @return an iterator for the Program of Study */ public Iterator iterator() { return list.iterator(); } /** * Saves a serialized version of this Program of Study to the specified * file name. * * @param fileName the file name under which the POS will be stored * @throws IOException */ public void save(String fileName) throws IOException { FileOutputStream fos = new FileOutputStream(fileName); ObjectOutputStream oos = new ObjectOutputStream(fos); oos.writeObject(this); oos.flush(); oos.close(); }

/** * Loads a serialized Program of Study from the specified file. * * @param fileName the file from which the POS is read * @return the loaded Program of Study * @throws IOException * @throws ClassNotFoundException */ public static ProgramOfStudy load(String fileName) throws IOException, ClassNotFoundException { FileInputStream fis = new FileInputStream(fileName); ObjectInputStream ois = new ObjectInputStream(fis); ProgramOfStudy pos = (ProgramOfStudy) ois.readObject(); ois.close(); return pos; } }

/////////Course/////////////

import java.io.Serializable;

/** * Represents a course that might be taken by a student. * * @author Lewis and Chase * @version 4.0 */ public class Course implements Serializable { private String prefix; private int number; private String title; private String grade; /** * Constructs the course with the specified information. * * @param prefix the prefix of the course designation * @param number the number of the course designation * @param title the title of the course * @param grade the grade received for the course */ public Course(String prefix, int number, String title, String grade) { this.prefix = prefix; this.number = number; this.title = title; if (grade == null) this.grade = ""; else this.grade = grade; } /** * Constructs the course with the specified information, with no grade * established. * * @param prefix the prefix of the course designation * @param number the number of the course designation * @param title the title of the course */ public Course(String prefix, int number, String title) { this(prefix, number, title, ""); }

/** * Returns the prefix of the course designation. * * @return the prefix of the course designation */ public String getPrefix() { return prefix; } /** * Returns the number of the course designation. * * @return the number of the course designation */ public int getNumber() { return number; } /** * Returns the title of this course. * * @return the prefix of the course */ public String getTitle() { return title; } /** * Returns the grade for this course. * * @return the grade for this course */ public String getGrade() { return grade; } /** * Sets the grade for this course to the one specified. * * @param grade the new grade for the course */ public void setGrade(String grade) { this.grade = grade; } /** * Returns true if this course has been taken (if a grade has been received). * * @return true if this course has been taken and false otherwise */ public boolean taken() { return !grade.equals(""); } /** * Determines if this course is equal to the one specified, based on the * course designation (prefix and number). * * @return true if this course is equal to the parameter */ public boolean equals(Object other) { boolean result = false; if (other instanceof Course) { Course otherCourse = (Course) other; if (prefix.equals(otherCourse.getPrefix()) && number == otherCourse.getNumber()) result = true; } return result; } /** * Creates and returns a string representation of this course. * * @return a string representation of the course */ public String toString() { String result = prefix + " " + number + ": " + title; if (!grade.equals("")) result += " [" + grade + "]"; return result; } }