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--- writing_classes_practice [2022/10/01 12:48] – frchris
+++ writing_classes_practice [2022/10/01 14:45] (current) – [Writing Classes Practice] frchris
@@ Line 1: / Line 1: @@
 ====== Writing Classes Practice ======
+These are designed to be done with an actual computer.  You would need to write the class from scratch and use the Tester class to see how your work is progressing.  Usually when you write a class for a Quiz, Test, or Exam, the task will be simpler (since you have no computer).  You learn a lot by finding and fixing mistakes yourself on a computer, which is why this is such great practice.
+===== Clock =====
+   - The Clock class should have three fields: hours minutes and seconds
+   - There should be a constructor that takes three values and initializes the fields
+   - There should be a ''toString'' method so that it returns a string with the current time.  (For example "12:52:34"
+   - There should be a method called ''tick'' that advances the seconds by one and sees if the minutes and hours need to be changed.  For example, if the current time is 11:59:59, after the method is called, the time should become "12:00:00";
+<code java ClockTester.java>
+import java.awt.Color;
+import java.awt.Font;
+import java.awt.Graphics;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.awt.event.KeyEvent;
+import java.awt.event.KeyListener;
+import javax.swing.JFrame;
+import javax.swing.JPanel;
+import javax.swing.Timer;
+public class ClockTester extends JPanel implements  ActionListener
+{
+	public static int WIDTH=800;
+	public static int HEIGHT=600;
+	private Font titleFont, regularFont, clockFont;
+	private int x;
+	private Timer motion, pulse;
+    private Clock clock;
+	public ClockTester()
+	{
+		//initialize variables here...
+		titleFont = new Font("Roman", Font.BOLD, 18);
+		clockFont = new Font("Roman", Font.BOLD, 72);
+		regularFont = new Font("Helvetica", Font.PLAIN, 12);
+		x=0;
+		motion = new Timer(2, this); //1000=1 seconds
+		pulse = new Timer(1000, this); //1000=1 seconds
+		clock =new Clock(11, 59, 50);
+		motion.start();
+		pulse.start();
+	}
+	public static void main(String[] args) {
+		ClockTester app= new ClockTester();
+		JFrame window = new JFrame("Clock Tester");
+		window.setSize(WIDTH, HEIGHT);
+		window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+		window.getContentPane().add(app);
+		window.setVisible(true);
+	}
+	public void paintComponent(Graphics g){
+		super.paintComponent(g);
+		g.setColor(Color.WHITE);
+		g.fillRect(0, 0, getWidth(),getHeight());
+		g.setColor(Color.BLUE);
+		g.setFont(titleFont);
+		g.drawString("Clock Tester", 20, 20);
+		g.setColor(Color.BLACK);
+		g.setFont(regularFont);
+		//g.drawString("pulse = "+x, 20, 40);
+		g.fillOval(x, 200, 10, 10);
+		g.setColor(Color.RED);
+		g.setFont(clockFont);
+		g.drawString(clock.toString(), getWidth()/3, getHeight()/2);
+	}
+	public void actionPerformed(ActionEvent e) {
+	     if (e.getSource()==motion){
+	    	 x=(x+1)%WIDTH;
+	     } else {
+	    	 // call the tick method
+	    	 clock.tick();
+	     }
+	     repaint();
+	}
+}
+</code>
@@ Line 44: / Line 134: @@
 	 * @param args
 	 */
-	public static void main(String[] args) {
+	public static void main(String[] args)
-		Song song=new Song();
+        {
-		Scanner keyboard=new Scanner(System.in);
+	   Song song=new Song();
-		String input="";
+	   Scanner keyboard=new Scanner(System.in);
-		while (input.indexOf("q")<0)
+	   String input="";
-		{
+	   while (input.indexOf("q")<0)
-			processCommand(keyboard, song, input);
+	   {
-			System.out.println("\nCurrently: "+song+"\n");
+		processCommand(keyboard, song, input);
-			System.out.print("Command (Title, Artist, Rank, Time, Plays, Quit): ");
+		System.out.println("\nCurrently: "+song+"\n");
-			input=keyboard.nextLine();
+		System.out.print("Command (Title, Artist, Rank, Time, Plays, Quit): ");
-			input=input.toLowerCase();
+		input=keyboard.nextLine();
+		input=input.toLowerCase();
-		}
+	   }
-		System.out.println("\nThanks.. we exit with the song being:\n"+song);
+	   System.out.println("\nThanks.. we exit with the song being:\n"+song);
 	}
 	public static void processCommand(Scanner keyboard, Song song, String input){
-		if (input.equals("title"))
+	   if (input.equals("title"))
-		{
+	   {
-			System.out.print("Currently: "+song.getTitle()+"\nNew Title: ");
+		System.out.print("Currently: "+song.getTitle()+"\nNew Title: ");
-			song.setTitle(keyboard.nextLine());
+		song.setTitle(keyboard.nextLine());
-		}
+	   } else if (input.equals("artist"))
-		else if (input.equals("artist"))
+	   {
-		{
+		System.out.print("Currently: "+song.getArtist()+"\nNew artist name: ");
-				System.out.print("Currently: "+song.getArtist()+"\nNew artist name: ");
+		song.setArtist(keyboard.nextLine());
-				song.setArtist(keyboard.nextLine());
+	   } else if (input.equals("rank"))
-		}
+	   {
-		else if (input.equals("rank"))
+		System.out.print("Currently: "+song.getRank()+"\nNew rank: ");
-		{
+		int newRank=Integer.parseInt(keyboard.nextLine());
-			System.out.print("Currently: "+song.getRank()+"\nNew rank: ");
+		song.setRank(newRank);
-			int newRank=Integer.parseInt(keyboard.nextLine());
+	   } else if (input.equals("time"))
-			song.setRank(newRank);
+	   {
-		}
+		System.out.print("Currently: "+song.getTime()+"\nNew time: ");
-		else if (input.equals("time"))
+		double newTime=Double.parseDouble(keyboard.nextLine());
-		{
+		song.setTime(newTime);
-			System.out.print("Currently: "+song.getTime()+"\nNew time: ");
+	   } else if (input.equals("plays"))
-			double newTime=Double.parseDouble(keyboard.nextLine());
+	   {
-			song.setTime(newTime);
+		System.out.print("Currently: "+song.getPlayCount()+"\nNew number of plays: ");
-		}
+		int newPlays=Integer.parseInt(keyboard.nextLine());
-		else if (input.equals("plays"))
+		song.setPlayCount(newPlays);
-		{
+  	    }
-			System.out.print("Currently: "+song.getPlayCount()+"\nNew number of plays: ");
-			int newPlays=Integer.parseInt(keyboard.nextLine());
-			song.setPlayCount(newPlays);
-		}
 	}