INFO 2313: Project. School of Business Kwantlen Polytechnic University. Nov 19, 2016 It is due at 12:00 PM (noon) on Sunday, Dec 4, 2016

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1 INFO 2313: Project School of Business Kwantlen Polytechnic University Nov 19, 2016 It is due at 12:00 PM (noon) on Sunday, Dec 4, 2016 This assignment focuses on using Object Oriented Programming (OOP) paradigm to solve a real world programming problem. You are going to implement a simple scheduling application. Scheduling problems typically arise around constraints over allocation of time slots and allocation of resources. They constitute a hot topic in analysis and study of algorithms. We, however, will consider a very simple case study. The optimal scheduling strategy (solution) is also provided to you. Your task is to simply implement the application as described here, using your Java programming skills and knowledge of OOP. 1 Prologue Suppose we have a group of proposed talks with preset start and end times. We want to schedule as many of these talks as possible in a lecture hall, under the assumptions that once a talk starts, it continues until it ends, no two talks can proceed at the same time, and a talk can begin at the same time another one ends. To schedule the most talks, that is, an optimal schedule, we need to decide how to choose which talk to add to our schedule. There are many criteria we could use to select a talk. However, it can be shown that the optimal solution is to add talks in order of earliest finish time. 1 Fo example, suppose that we have three talks: Talk 1 starts at 8 a.m. and ends at 11 a.m. Talk 2 starts at 9 a.m. and ends at 10 a.m. and Talk 3 starts at 10 a.m. and ends at 12 noon. We select Talk 2 because it has the earliest ending time. Once we selected Talk 2, we cannot select Talk 1 because it overlaps with Talk 2. On the other hand, Talk 3 is compatible with Talk 2. Hence, we select it to go next after Talk 2 is finished. Algorithm-1 describes our scheduling strategy. 1 We have discussed this during a lecture with examples of other criterion. 1

2 Algorithm 1 Greedy Algorithm for Scheduling Talks. Input: a list of talks l = {t 1, t 2,..., t n } with start and ending time. Output: a schedule s of talks to be held in the lecture hall (s l). 1: Sort talks t j by finish time. 2: Add the first talk t 1 to the schedule s. 3: for each talk t i in the sorted list l do 4: if t i is compatible with the last talk t in scheulde s then 5: Add t i to the schedule s. 6: end if 7: end for 8: Return the schedule s. 2 The Application As you run the application, it will present you with four options: Welcome to Scheduler Application! >> MAIN MENU << 1. Add an event 2. Display events 3. Schedule 4. Exit >> Select your option (1-4) : Upon selecting option 1, user will be presented with the Event Menu: >> Select your option (1-3) : There are two types of events: talk and lecture. A talk has a start time and duration whereas a lecture length is fixed to 60 minutes. User can add as many talks and lectures as needed. A few examples follow. Note that User does not enter the end time for an event. User does not enter duration for a lecture. User can add overlapping events. INFO

3 >> Select your option (1-3) : 1 Enter the title of the talk : Global warming Enter the start time Hour (0-23) : 8 Minute (0-59) : 0 Enter talk ' s duration ( in minutes ): 90 >> Select your option (1-3) : 2 Enter the title of the lecture : Climate vs. Weather Enter the start time Hour (0-23) : 9 Minute (0-59) : 0 >> Select your option (1-3) : 1 Enter the title of the talk : Climate change : the big picture. Enter the start time Hour (0-23) : 9 Minute (0-59) : 45 Enter talk ' s duration ( in minutes ): 75 INFO

4 Upon returning to the main menu, user can select option 2, to see a list of all events. >> MAIN MENU << 1. Add an Event 2. Display Events 3. Schedule 4. Exit >> Select your option (1-4) : 2 Events : Talk : Global warming ( 08: 00 AM to 09: 30 AM) Lecture : Climate vs. Weather ( 09: 00 AM to 10: 00 AM) Talk : Climate change : the big picture. ( 09: 45 AM to 11: 00 AM) By selecting option 3, your program must apply the scheduling algorithm (Alg 1) to the events and print out the optimal schedule. >> MAIN MENU << 1. Add an Event 2. Display Events 3. Schedule 4. Exit >> Select your option (1-4) : 3 Schedule : Talk : Global warming ( 08: 00 AM to 09: 30 AM) Talk : Climate change : the big picture. ( 09: 45 AM to 11: 00 AM) Your application must perform input validation and sanity checks. It is left to you to think about all invalid cases and appropriate ways to handle them. 3 What is expected of you? You are expected to create an object-oriented solution for the implementation of this application. This means creating classes and objects among other things. You must try to incorporate all that you have learned in this course into your implementation. Your solution ideally showcases encapsulation, object composition, inheritance, polymorphism and exception handling. It is up to you to design and structure your code. However, I expected to see at least three classes in your project: Event, Scheduler, and Application. The Event class, as its name suggests, encapsulates an event. The Scheduler class implements the scheduling algorithm. The Application class implements the userinterface. There must be a clear separation between the job of these classes. For instance, the Event and Scheduler classes must not contain any System.out.print statements since such statement is too specific to the console application (the user-interface for this assignment). INFO

5 Each class must have appropriate instance variables, constructor(s), getter and setter methods (if needed) as well as other mutator and accessor methods. The mutator methods must validate their arguments. 4 What to submit? You will submit: 1. The completed project. 2. A short (one page; two sides) report. The report must contain two sections: 1. A short essay on how object-oriented programming is used to implement this application. Discuss the idea of OOP, note how e.g. encapsulation, inheritance (and other aspects of OOP) are used in your project. Elaborate on benefits and challenges of object-oriented design, etc. 2. A UML class diagram of all the classes used for this project. The relationships between the classes must be displayed in your diagram. The essay must not exceed one page in length. As a general rule of thumb, a typical page which has 1-inch margins and is typed in 12 point font with standard spacing elements will be approximately 500 words when typed single spaced. Make sure that you typeset the report and draw the UML diagram using a professional software tool. 2 The report is as important to me as your implementation because it demonstrates your understating of the material covered in this course. You must submit the Java project for this assignment which you have created with Eclipse. Your report must be converted to a PDF file and copied inside the project folder. If you have any doubt as to what you need to submit, please make sure to consult with me before making the submission. You are permitted to work in groups of two but you must each submit a copy of your project to Moodle. If you have worked in a group, make note of it in your report. 2 Do not use software that automatically generate UML from source code. This will be considered as cheating and you will receive a zero mark for it. INFO

6 Apendix: Sorting The first step of Alg 1 is to sort the list of events in order of earliest finish time. I will describe a general sorting strategy below which can be applied to this problem as well. For simplicity, we will consider a list (array) of numbers. Algorithm 2 can be used to sort an array of numbers in ascending order. Algorithm 2 Simple Sort Input: A list of numbers L. Output: The ordered version of input. 1: Set N to be the number of elements in L. 2: for i=1 to N-1 do 3: for j=i+1 to N do 4: if L(j) < L(i) then 5: Swap element L(i) with element L(j). 6: end if 7: end for 8: end for 9: Return L This algorithm starts with the first element in the list. It compares it with every other element. During the comparisons, if elements are not in order, they will be swapped. Thus, by the end of the first pass, the first element will be the smallest number in the list. This process will be repeated for every element in the list. INFO