Final Examination Semester 3 / Year 2012

Transcription

1 Final Examination Semester 3 / Year 2012 COURSE : ADVANCED JAVA PROGRAMMING COURSE CODE : PROG 2114 TIME : 2 1/2 HOURS DEPARTMENT : COMPUTER SCIENCE LECTURER : LIM PEI GEOK Student s ID : Batch No. : Notes to candidates: 1) The question paper consists of 8 pages Section A: 10 questions (20 marks) Section B: 2 questions (20 marks) Section C: 2 questions (60 marks) 2) Answer all questions. 3) Write your answer for Section A and Section B in answer booklet. 4) Save your answer for questions in Section C and submit your answers in softcopy to Southern College E-Learning System.

2 SECTION A: MULTIPLE CHOICE QUESTION (10 X 2 = 20 MARKS) Please choose most appropriate answer. State the answer in the answer booklet. 1. Which of the following groups of overload constructors are valid? a. public Cat(int age) { public Cat(double wgt) { b. public Dog(String name, double weight) { public Dog(String name, double height) { c. public Dog(String name, double weight) { public Dog(double weight, String name) { d. public Cat(String name) { public Cat(String weight) { public Cat(double height) { 2. Assume a working program contains the following statement: mydog.setname( Bowser ); Which of the following do you know? a. setname() is a public method b. setname() accepts a string parameter c. Both of these d. None of these 3. Which of the following is true? a. A subclass inherits all the members of its ancestors. b. A subclass inherits all the public members of its ancestors. c. A subclass inherits only the private members of its ancestors. d. A subclass inherits none of the members of its ancestors. 4. The method tostring() is a public member of the class. a. Object b. Writer c. String d. Output 5. If more than one method shares the same name, then we say they are overloaded methods. Which of the following condition will make the overloaded methods invalid? a. The number of parameters is different. b. The number of parameters is same, but the data types of the parameters are different. c. Both of the number of parameters and data types of the parameters is the same. d. Both of the number of parameters and the data types of the parameters is different. 1/7

3 6. You can use to check whether an object is an instance of a class. a. new b. static c. instanceof d. super 7. Suppose that Car and Motorcycle are subclass of Vehicle. Which of the following statement is VALID for create an object of Car? a. Vehicle a = new Car(); b. Car a = new Motocycle(); c. Vehicle a = new Motocycle(); d. Car a = new Vehicle(); 8. Which of the following statements is FALSE? a. An abstract class can be extended b. A subclass of a non-abstract superclass can be abstract. c. A class contains abstract methods must be abstract. d. You can create instances of abstract classes using the new operator. 9. An interface can extends interface/s. a. none b. only one c. one or more d. All of above 10. Which of the following class definitions defines a legal interface class? a. interface A{ b. void print(){ ; c. abstract interface A{ d. print(); abstract interface A extends T1,T2{ Abstract void print() {; interface A{ void print(); 2/7

4 SECTION B: SHORT QUESTIONS (20 MARKS) Answer all the questions in answer booklet. Question 1 (10 marks) a) There is one error in the following codes. Identify the error and rewrite the statement with correct codes. (3 marks) 1 public class Test { 2 public static void main (String ary[ ]){ 3 display(new Box()); 4 display(new WoddenBox()); 5 6 public static void display(box x) { 7 if(woddenbox instanceof x) 8 ((WoddenBox)x).info(); class Box{ 12 void info(){ 13 System.out.println("This is a simple box"); class WoddenBox extends Box{ 17 void info( ){ 18 System.out.println("This is a Wodden box"); b) There is one error in the following codes. Identify the error and rewrite the statement with correct codes. (3 marks) 1 class Vehicle { 2 abstract public void getvin(); 3 c) Consider the following class. class Modifier { public static void change (int x, int y){ x = x 10; y = y + 10; What will be the output of the following code? (4 marks) 3/7

5 public class Test { public static void main (String ary[ ]){ int x = 40; int y = 20; Modifier.change(x, y); System.out.println( x = + x); System.out.println( y = + y); ADVANCED JAVA PROGRAMMING Question 2 (10 marks) a. What modifier should you use on a class so that a class in the different package cannot access it, but its subclasses in any package can access it? (2 marks) b. If a method in a subclass has the same signature as a method in its superclass with the same return type, is the method overridden or overloaded? (2 marks) c. If a class implements Comparable, the object of the class can invoke the compareto method. Indicate true or false. (2 marks) d. Can you invoke the clone() method to clone an object if the class for the object does not implement the java.lang.cloneable? (2 marks) e. Give an example of the classes in the Java library that implement Cloneable. (2 marks) 4/7

6 SECTION C: CODING QUESTIONS (60 MARKS) Submit your answer in softcopy and upload it to Southern E-Learning System. Question 1 (40 marks) The IT manager of the Travel Plus Company hired you to work on the bus ticket order system. Your job scope is to design a system to calculate the bus ticket price based on different categories of bus ticket. Complete the following task: a) Create an abstract class named Ticket that includes data fields that holds bus number (for example, JKK1234 ), seat number (for example, V1 ), ticket number (auto-generated number) and ticket price (for example, 30.00). Write two types of constructor which include default constructor and constructor that requires the bus number and ticket price. Write the accessor methods for all the attributes in Ticket class. Write the mutator method for bus number and ticket number. Write the calculatetotalpayment() method to calculate the overall payment of ordered ticket after added service charge and government service tax. Write a void displayreceipt() method to display the information of the ordered ticket. Write two abstract methods with void return type which include setseatno() and setticketprice(ticket price). (21 marks) Attributes/Methods Descriptions Seat number It depends on the categories of ticket which includes VIP and economic ticket. Ticket number It will be auto-generated by your system. For example, the ticket number for the first ticket is 1 and the ticket number for second ticket is 2. displayreceipt() It is a void method that used to display the receipt as follows: Receipt***** Ticket No. : 1 Bus No. : JKK1234 Seat No. : V1 Ticket Price : RM Total Payment : RM calculatetotalpayment() It a method that used to calculate ticket price by added 10% service charge and 6% government service tax. b) Create a subclass named VIPTicket. Write appropriate constructor/s. You may need to use an attribute to keep track the current seat no of VIP ticket. Write the implementation for the setseatno() and setticketprice(ticket price) method. (10 marks) Attributes/Methods Descriptions void setseatno() Seat number start from V1 to V10. Only 10 seats available. 5/7

7 Your system should display VIP seat already full. if the entire VIP seat already booked. void setticketprice(double The parameter used to specify the ticket price ticketprice) of economic ticket. VIP ticket is 40% expensive that the economic ticket. c) Create a subclass named EconomicTicket. Write appropriate constructor/s. You may need to use an attribute to keep track the current seat no of Economic ticket. Write the implementation for the setseatno() and setticketprice(ticket price) method. (9 marks) Attributes/Methods Descriptions void setseatno() Seat number start from E10 to E30. Maximum 20 seats for economic class. Your system should display Economic seat already full. if the entire Economic seat already booked. void setticketprice(double ticketprice) The parameter used to specify the ticket price of economic ticket. The sample output is shows as follow. Sample output: Receipt***** Ticket No. : 1 Bus No. : JKK1234 Seat No. : V1 Ticket Price : RM Total Payment : RM Receipt***** Ticket No. : 2 Bus No. : JKK1234 Seat No. : E11 Ticket Price : RM 80.0 Total Payment : RM 92.8 Receipt***** Ticket No. : 3 Bus No. : JKK1234 Seat No. : V2 Ticket Price : RM Total Payment : RM /7

8 Question 2 (20 marks) Write a class named FixedInvestment that implements the Comparable interfaces. Required: a) A double data field named depositamout that specifies the investment amount (default 1000). b) A double data field named annualinterestrate that specifies the fixed interest rate. (default 5.0%) c) An int data field named numberofyear that specifies the investment duration. (default 1) d) A constructor that create an instance with the specified depositamount, annualinterestrate and numberofyear. e) Accessor and mutator methods for all the data fields. f) A gettotalreturn() method that returns the investment return after the specified number of years. The total return can be computed using the following formula: numberofyear x 12 totalreturn = investmentamount x (1+monthlyInterestRate) The objects of FixedInvestment class should compare based on their total return /7