[SOLVED] COMPSCI 4039 PROGRAMMING IT 2022 Java

PROGRAMMING IT

(COMPSCI 4039)

Monday 12 December 2022

Important note: throughout this exam, whenever you are asked to write Java code, do not worry about whether your code compiles.  The markers will never test any submitted code from this exam.

1.    (a) The International Olympic committee are designing an IT system, built in Java, that will

record the medal tables in their summer and winter games. The following class will be used to represent a team:

public class	Team {
private	String name;
private	int numGold;
private	int numSilver;
private	int numBronze;
}

Here, name is the team name (for instance, “Ireland”), and numGold, numSilver, and numBronze are the total numbers of gold, silver and bronze medals that the team has accumulated so far in the competition.

(i)  Write a constructor for the Team class that is called bypassing only the team name. This should set name to be the passed string and initialise numGold, numSilver and numBronze to 0. [3]

(ii)  Write a second constructor that takes four parameters to add a team to the table after

they have already been awarded medals. The four parameters should be the team name String as well as three integers for the numbers of medals already won by that team.  [4]

(b) Create getter and setter methods for the name string and the three integer attributes (i.e. the medal counts) of the Team class.  [8]

2.    (a) Since each team can only win at most 1 medal of each kind for any given event, overload the setter methods for the medal counts so that the new version is passed no parameters and simply increments the count by 1. [3]

(b) Create a method within the Team class that will allow the team name and medal counts

for each team to be printed out using a System .out .println(t), where tis a Team object. The team name, number of golds, number of silver and number of bronze should be printed out in that order, in the fixed width order given below (note that the periods should be printed as spaces – periods are just being used in this diagram so you can count them easily):

Australia . . . . . . | . . . 17 | . . . .7 | . . .22                                      [7]

(c) A class in now required to hold the leaderboard for the games, in an array of Team objects. Part of this class is as follows:

public  class  Leaderboard  {

private  int  numTeams;

private  Team[]  teams;

}

Write a constructor for this leaderboard class. The constructor should take a single parameter, an integer representing the number of Teams competing at the games. The number of teams should be stored in numTeams and this value should be used to instantiate teams, the array of Team objects.   [3]

(d) Give the command that could have been used to initialise a leaderboard for this year’s Beijing Winter Olympics, in which 91 teams took part.   [2]

3.    (a) The code shown below is an attempt by the college in printing a simple welcoming message for the new students of this semester.  Unfortunately, the code will not work.  Identify 4 mistakes that can be found in the code.

public  class  Welcome  New  Students  {

static  void  main(String[]  args)  {

System .out .println(Welcome  students!)

}

}                                                                                                    [4]

(b) The college is asking developers to find a way of sorting out the student’s records.

(i)  In the first part the developers need to identify the highest grade.

You are asked to create a methods that can be used to identify and print out the highest grade.

Assume that the marks are in an integer format and the records are saved as an array. For the array use the values 25, 89, 95, 60, 45,78. [7]

(ii)  Write another function in the same class you created for Q3bi in order to identify the

lowest grade. The lowest grade should also be printed. All the details are the same as presented in 3bi.   [4]

4.    (a) One student’s surname was entered wrongly in the students’ text record. His surname was “Ferguson” but the entry was “Farguson” .

(i)  Write a method that can easily check if the wrongly typed student’s surname is in the text file. This means that the method should return true if the line is found or false if  it is not. Assume that the path of the file is just “filepath”, the name of the text file is “Srecord” and no newline characters are included. Error handling for FileNotFound  should be considered.                                            [4]

(ii)  After producing code for reading the text file (4ai) include additional code that should be included in the previous method, for replacing the wrong surname (Farguson) with the correct one (Ferguson). Make sure to include a printout of the updated surname.   [2]

(iii)  What would be the difference if we wanted to replace any entries having the surname “Farguson” with an empty line?  Write how the previous code from 4aii would be modified so the entry ”Farguson” would be replaced with an empty line instead.

Write the relevant code.                                                                                               [1]

(b) For the same course a string array was created called “Sname” which produces as an output the names of the students in an alphabetical order.  The following names were included (Thomas,Amaya, Gustavo, Melina, Reirse, Bell). This is a bad coding example and there are several mistakes in the code. You are asked to identify 8 mistakes and point them out, explaining them.

Class  AlphName{

public  static  void  main{ int  n  =  0;

String  Sname[]  =  {“Thomas,  Amaya,  Gustavo, Melina,  Reirse,  Bell”};

String  temp

for   (int  i  =  0;  i  < n;) {

for   (  k  =  100;  k  < n; k++) {

if   (Sname[i] .compareTo(Sname[k])  >0{ temp  =  Sname[i];

Sname[i]  =  Sname[k]; Sname[k]  =  temp;

} }

}

System .println(“Names  in  alphabetical  order:”); for   (int  i  =  0;  i  < n; i++) {

System .out .println(); }

} }

[8]