Question

Analyze the code to determine what the code does, how the data is structured, and why it is the appropriate data structure (i.e. linked list, stack or queue). Note that these are examples of classes and methods and do not include the "main" or "test" code needed to execute. When you are done with your analysis, add a header describing the purpose of the program (include a description of each class and method), the results of your analysis, and add detailed explanatory comments to the code. Then submit the updated file with your revisions (comments and header).

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;

public class ProgramOfStudy implements Iterable<Course>, Serializable

{

private List<Course> list;

public ProgramOfStudy()

{

list = new LinkedList<Course>();

}

public void addCourse(Course course)

{

if (course != null)

list.add(course);

}

public Course find(String prefix, int number)

{

for (Course course : list)

if (prefix.equals(course.getPrefix()) &&

number == course.getNumber())

return course;

return null;

}

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);

}

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);

}

public String toString()

{

String result = "";

for (Course course : list)

result += course + "\n";

return result;

}

public Iterator<Course> iterator()

{

return list.iterator();

}

public void save(String fileName) throws IOException

{

FileOutputStream fos = new FileOutputStream(fileName);

ObjectOutputStream oos = new ObjectOutputStream(fos);

• os.writeObject(this);
• os.flush();
• os.close();

}

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;

}

}

Answer 1

Answery : from, the above. Statement and condition the problem can. be solved by using the dollowing program In this. Java program is used to solve the problem... code 1 Header : Java Program to implement the priority quere data Structure using heaps. . . Ill this is achieved by extending the Arrayters from the priority, Queve class Il Prioritized object clous depines the prototype for each node on the CScanned with Cascanihee queue

ll and it implements the comparable interjoce that enables easy comparison between two Objects Il Data biding is implemented as: each dara member is declared private with getter methods for each lideyined separately Iclass Prioritizedobject delines a prototype for each sode in the ll priority queue data structure and each node stores l priority number (priority), order of arrival Carrival Order) Hand a comparable element element) public class prioritized object at> implements comparable Prioritized object> & Mvariables are declared private for the purpose of data hiding .. Il Static,: variable neoet onder 702 store the arrival order of the previous object and it increments: by one cach. time whenever an object is added to the queue private static int neset Order = 0; Il private variable to store the priority number private int priority, CS Scanned with CamScanner

ll private variable to store. the order of arrival private int arrival Order', Il a private com porrable Clement that. hold's generic I data pirtrate 7 element, 11 Prioritized object constructor to initalize the object Illand increment the static variable nest order public Prioritized Object IT element, int priority) this.element = element, this.panority = priority; arrival Order = nesct order, neset onder +t'; ir getter Method that itetinns the orelorence to the element og generic type poblic' TgetElements : Greturn elementi Wetter hethod that returns the priority Ojotticelliement - public int.qet Priority, return priority: C o with Canscanner

I getten Method that creturns the amiiral Ondest of the element public int get Arrival Order ) ute turn arrival orders ll this method returns, the ... element & priority and arrival Order of the element ll as a storinq cuith spaces between each of them . public string to string() veturn (elementt!" "tpriorite +""+ arrival order); 1 this method compares the two Prioritized objects on the basis of Priority and arrival Order ll and returns the result as: 11-7lig the calling object as of higher priority than the object passed as parametery 11-yild the calling object is of lower priority than the object passed as parameter i lly is the calling object arrived after the object passed as parameter CS Scanvered with CamScanner

11-y for all the wemaining cases public int compare to (Prioritized Object ob ) int mesult as (prioritys obj. get Priority() vresult = 1; else ij (priority a obj+get Priority cesultant .. elle il Carnival Order> obj.ger Arrival order(s) ...Cs014715.. else Hesult = -1 ज+00 , import j$1.*. 11 The class Priority queue implements a priority queue using a heap and generics public class Priority Queue 277 entends Arraytleapa Prioritized objecit etsy :ll Priority Queue constructor to create an empty priority queue CS Scanned with CamScanner

- public priority Queue (9 - Il call the super class constructor super(); 11 method to add the element to the queue, it takes a generic object 18 its priority as a parameter public void add'Etement (T object, int priority) II declare a new Prioritized object obj by passing object and priority Mas a parameter Prioritized Object <T> obj = new by passing Perio Prioritized object <T> Obj = new Prioritized Object <T> lobject, priority). Il call the super class method add element by passing the Object as para meter super. add Element cobj); 11 Remove Neset () viemoves the element with next highest priority in the priority queue CS Scanned with CamScanner

11 $ vretorne a gyerence to object public T chemore Nesetly . . ll call the superclass Junction remore mince using the new Prioritized object object Prioritized object <T> obja (Prioritized object <77 ) supen, oremove nincs ... 11 oleturn the viejetence to the element with next highest priority in the one priority queue cheturn obj.getElemente), CS Scanned with CamScanner

Screen shot of code (for - indentation Olejerence) Thank you. CS Scanned with CamScanner

1/ Java Program to implement the priority quee data structure using heaps. chieved by extende r fro the nortQuee class 3 // Prioritizedoject class defines the prototype for each node of the queue le interface that enables y comparison between two obtects // Data hiding is implemented as each data somber is declared private with getter methods for each defined separately 1 class Prioritizedbfect defines a prototype for each node in the 1/ priority quee data structure and each node stores 911 priority number priority), order of arrival (arrival Order) public class PrioritizedObject<T> implements Comparable Prioritizedeject> variables are declared private for the purpose of data hiding static variable nextOrder to store the arrival order of the previous abject 1/ and it increments by one each time whenever an object is added to the queue private static int nextOrdere; Il private variable to store the priority number private int priority; 1 private variable to store the order of arrival 13 private comparable element that holds generic data Il PrioritizedDogect constructor to initialize the object 1 and increment the static variable nextOrder public PrioritizedObject(T element, int priority) this.element - element; this.priority - priority: arrivalOrder - extOrder: sextOrder I etter method that returns the reference to the element of generic type public Trettlement return element; f ine etter that turns the priority of the element return priority 1 e r sethod that returns the arrivalOrder of the element

public int getArriva lorder() return arrivarer: this method returns the element & priority and arrival Order of the 1 as a string with sonces between each of them public String toString() return elemente riority arrivalorder); // this method compares the two Prioritizejects on the basis of Priority and arrival Order 11 - 1 the calling object is of higher priority than the object passed as parameter 11 -> -1 if the calling object is of lower priority than the object passed as parameter 11 - - 1 for all the remaining cases public int compareTo(PrioritizedObject by int result: If forority> 003.getPriority result - 1; else if (priority obj.getPriority()) resuit -1; else if (arrival Order > obj.getirrival Order() result = 1; result -1 return result; eart 1544. 115 // The class Priorityquee plements a priority Queue using heap and generics 116 public class Priority Queuect extends Arrayap Prioritizedbjectct 1/ Priority Queut constructor to create an empty priority queue pubesc Priority gueu 1/ call the superclass constructor

CIOPA e 1 porty O result = 1; else if (arrivalOrder > .getArrivalOrder > ESSES result = -1; return result; 115 /The class Priority Queue implements priority using heap and puneric 116 public class Priority Queue<T> extends Array PrioritizesObject<T>> // Priority Queve constructor to create an empty priority Queue public PriorityQueuel) call the superclass constructor method to add the element to the queue, it takes a generic object public void addelement (T abject, int priority) I declare a new PrioritizedObject ob by passing object and priority Prioritizeaject obj - new Prioritizeject<T>(object, priority); // call the superclass method ad Element by passing the object as parameter I removellext() removes the element with next highest priority in the priority queue public T removellext() Gece 11 the superclass function las function i n) using the new Prioritisect object Prioritizeboject T obj - Prioritizedoject i ner super.remove (); 1} return the reference to the element with next highest priority in the Il priority quee return opetElement();

CIOPA e 1 porty O result = 1; else if (arrivalOrder > .getArrivalOrder > ESSES result = -1; return result; 115 /The class Priority Queue implements priority using heap and puneric 116 public class Priority Queue<T> extends Array PrioritizesObject<T>> // Priority Queve constructor to create an empty priority Queue public PriorityQueuel) call the superclass constructor method to add the element to the queue, it takes a generic object public void addelement (T abject, int priority) I declare a new PrioritizedObject ob by passing object and priority Prioritizeaject obj - new Prioritizeject<T>(object, priority); // call the superclass method ad Element by passing the object as parameter I removellext() removes the element with next highest priority in the priority queue public T removellext() Gece 11 the superclass function las function i n) using the new Prioritisect object Prioritizeboject T obj - Prioritizedoject i ner super.remove (); 1} return the reference to the element with next highest priority in the Il priority quee return opetElement();