CSC1302 Assignment 4: Java Class, Objects Solution

Purpose:
A class is a blueprint or prototype from which objects/instances are created. It includes fields or methods that are common to all objects of the same blueprint/class. In general, a class declaration has components: class header, constructors, methods such as getter/setter, and so on. The constructors are used for initializing new instances. Fields are variables representing the state of the class and its objects. The methods are used to implement the behavior of the class and its objects.
In this assignment, we will practice how to define classes and create objects. Once a class is available, it’s like we have a new data type. Variables can be defined with a type of this class and can refer to an object of this class. Methods can use this class as parameter type or return type.
Program #1:
Add divide method to take another Fraction as the parameter and return a new Fraction that is the division of current Fraction and the Fraction in the parameter. (public Fraction divide(Fraction f)).
- Add scaleup and scaledown methods to the Fraction class. The scaleup method will take a factor as the parameter and multiply the numerator by the factor. The scaledown method will take a factor as the parameter and multiply the denominator by the factor.
- Add a scale method which will have two parameters: factor and flag. The flag is boolean. If flag is true, then scale up the fraction; otherwise scale down the fraction.
- Add two more constructors. One of the constructors will have no parameters; it initializes the fraction to 0/1. The other constructor will have one parameter, representing the numerator of the fraction; the denominator of the fraction will be 1.
- Write a program named FractionScale that prompts the user of a fraction and a scale factor. Here is what the user will see on the screen:
This program performs the scaling operations on a fraction.
Enter a fraction: 3/7
Scale up or down (1: up, 0: down): 1
Enter a scale factor: 2
Scaled fraction is: 6/7

public int getDenominator() {
return denominator;
}
public Fraction add(Fraction f) {
int num = numerator * f.denominator +
f.numerator * denominator; int denom = denominator * f.denominator; return new Fraction(num, denom);
}
}
Program #2:
Following is a part of the source codes for NBATeam and NBA classes. Finish the programs for both classes to produce an output screen similar to the following figure.

//File NBA.java
import java.util.Scanner;
public class NBA {
public static void main(String[] args) {
Scanner input = new Scanner (System.in);
String ifAddPlayer;
String playerName;
//construct Team Heat
System.out.println("Creat the NBA team of Heats ...... ");
NBATeam heat= new NBATeam("Heats");
System.out.print("Add a play to Heats? (yes/no): "); ifAddPlayer= input.next();
while (ifAddPlayer.equalsIgnoreCase("yes")){
System.out.print("What is the name to be added? "); playerName=input.next(); heat.addAPlayer(playerName);
System.out.print("Add one more play to Heats?
(yes/no): "); ifAddPlayer= input.next();
}
//construct Team spurs
…………………………//Your code here
/*simulate a series of atmost 7 games by generating a random number; if the random number is bigger than 0.5, Heat wins; otherwise Heat losses a game. As soon as team wins 4 games, the series is over. */
…………………………//Your code here
System.out.println(heat);
System.out.println(spurs);
}
}
//File NBATeam.java
public class NBATeam { private String sTeamName; private int nWin; private int nLoss;
private String [] playerArray;
…………………………//Your code here
}//end of class definition
Criteria:
1. Upload all of the .java and the .class files to the CSc1302 dropbox on http:// icollege.gsu.edu.
3. Make sure that both the .java and .class files are named and uploaded to icollege correctly. If any special package is used in the program, be sure to upload the package too. Should you use any other subdirectory (whatsoever) your program would not be graded, and you will receive a 0 (zero).
4. No copying allowed. If it is found that students copy from each other, all of these programs will get 0.