Practical Coding in Java

//
// HighScoreDemo.java
//


//
// This program demonstrates the use of the Processing functions
// loadStrings() and saveStrings() to implement a high score list.
//
// High scores are stored in a file "high_scores.txt" as strings:
//
// DrKessner 1234 
// Gadget 2345
//
// Called in setup(), the readHighScores() function reads the
// contents of "high_scores.txt" as a list of strings, one string
// per line, and then transforms this list to a list of high score
// records.
//
// The keyPressed() function demonstrates how to add a new high
// score and save the scores to the "high_scores.txt".
//


import processing.core.*;
import java.util.*;


public class HighScoreDemo extends PApplet
{
    public void settings()
    {
        size(400, 400);
    }

    public void setup()
    {
        // read the high scores from file

        readHighScores();

        // print the high score records

        for (HighScoreRecord r : highScoreRecords)
            System.out.println(r.getName() + " " + r.getScore());
    }

    public void draw()
    {
        background(0);
    }

    public void keyPressed()
    {
        // add a new high score

        highScoreRecords.add(new HighScoreRecord("Tux", 3456));

        // write the high scores to file

        writeHighScores();
    }

    private void readHighScores()
    {
        // call the PApplet loadStrings() function

        String[] highScoreStrings = loadStrings("high_scores.txt");        

        // transform the list of strings into a list of high score
        // records

        highScoreRecords = new ArrayList<HighScoreRecord>();

        for (String s : highScoreStrings)
        {
            // parse the line and add a new record to the list

            String[] tokens = s.split(" ");

            String name = tokens[0];
            int score = Integer.parseInt(tokens[1]);

            highScoreRecords.add(new HighScoreRecord(name, score));
        }
    }

    private void writeHighScores()
    {
        String[] highScoreStrings = new String[highScoreRecords.size()];

        // transform the list of high score records to a list of
        // strings

        for (int i=0; i<highScoreStrings.length; i++)
        {
            HighScoreRecord currentRecord = highScoreRecords.get(i);

            highScoreStrings[i] = currentRecord.getName() + " " 
                + currentRecord.getScore();
        }

        // call the PApplet saveStrings() function

        saveStrings("high_scores.txt", highScoreStrings);
    }

    private ArrayList<HighScoreRecord> highScoreRecords;

    public static void main(String[] args)
    {
        PApplet.main("HighScoreDemo");
    }
}

//
// HighScoreRecord.java
//


public class HighScoreRecord
{
    public HighScoreRecord(String name, int score)
    {
        this.name = name;
        this.score = score;
    }

    public String getName() {return name;}
    public int getScore() {return score;}

    private String name;
    private int score;
}