Lab 10

CSCI 1913 – Introduction to Algorithms, Data Structures, and Program Development

Set up environment

Start an IntelliJ project
Download the files for this project and move the .java to the src folder
The image files must be placed correctly. These should go in the root folder of the project (NOT in src) – if these are misplaced you will have trouble getting tests to run

Folder Structure

Your intelij project directory should look something like the following:

.
lab10
|-- out
`-- src
    |-- GameScoreTester.java
    |-- LeaderBoard.java
    `-- LeaderBoardTester.jav

CreateGameScore.java in the src folder

GameScore

The game score class will represent a single item in a classic video-game score board:

example of a video-game score board

GameScore

The first thing you’ll want to do is make a GameScore class. This should have 3 private instance variables:

the score (a double)
the name for this record (a String)
a boolean indicating if this score was earned on hard mode (true) or easy mode (false)

GameScore

Implement the following methods:

public GameScore(String name, double score, boolean hardMode) a constructor for this class.
public String getName() getter for the name property
public double getScore() getter for the score property
public boolean isHardMode() getter for the hardMode flag – returns true if the game was hardmode.
public String toString()
public boolean equals(Object o)

Make it Comparable

Your final task with this class is to make it Comparable. To begin, update the class declaration as follows:

    public class GameScore implements Comparable<GameScore>

LeaderBoard

You should begin by writing the three easy methods:

public int getSize() get the size of the leaderboard.
public T highScore() get the largest value in the leaderboard
public T lowScore() get the smallest value in the leaderboard

All three of these methods should be easy 1-line methods which run in time \(O(1)\).

Javadoc

Key Rules:

Starts with /** and ends with */
First sentence is a short summary — it appears in the generated HTML overview
@param tag should be listed for every parameter

Javadoc

   /**                                                                               
   * Calculates the average of an array of test scores.
   * Returns 0 if the array is null or empty.    
   *              
   * @param scores  an array of test scores, each in the range [0, 100]
   * @param count   the number of scores in the array
   * @return        the average of all scores, or 0 if the array is null or empty
   * @throws        IllegalArgumentException if count is negative
   *
   * @author        Adriana Picoral
   * @version       1.0
   */
  public double calculateAverage(double[] scores, int count) {
      if (scores == null || scores.length == 0) return 0;
      if (count < 0) throw new IllegalArgumentException("Count cannot be negative");

      double sum = 0;
      for (double score : scores) {
          sum += score;
      }
      return sum / count;
  }