Java Clock

Hey everyone,

I'm just posting this clock/timer applet I created. It's nothing special, just a timer - I find it very usefull when I listen to the footy on the radio. If any Aussies here follow the AFL, hopefully you'll know what I mean. Well anyways, if you are learning java, I'm hoping this will be a good example for you. I find that example applets/applications are really good to learn from - you can't just read text books...too boring.

Well, I'll post the source code here and hopefully my poor documentation will explain most of the things. :)

(Note: It's java, even though I put it in PHP quotes - it just looked the best in them - I tried 'code' quotes, but it was all over the place.)

PHP Code:

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//import the packages that will be used
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

//define the class Clock
public class Clock extends JApplet implements ActionListener
{
    //define all instance variables
    private Container pane;
    private JPanel center, south;
    private JLabel hours, minutes, seconds;
    private JTextField hourValue, minuteValue, secondValue;
    private JButton startButton, stopButton;
    private String theHour, theMinute, theSecond;
    private Timer theTimer;

    //define the init method, which basically outlines what the applet looks like
    public void init()
    {
        //define the pane where everything will be added
        pane = getContentPane();
        //define what layout the pane will use
        pane.setLayout(new BorderLayout());

        center = new JPanel();
        center.setLayout(new FlowLayout());
        pane.add(center, "Center");
        south = new JPanel();
        south.setLayout(new FlowLayout());
        pane.add(south, "South");

        //define the labels
        hours = new JLabel("Hours");
        minutes = new JLabel("Minutes");
        seconds = new JLabel("Seconds");

        //define the text fields - the actual timer
        hourValue = new JTextField("0", 3);
        minuteValue = new JTextField("0", 3);
        secondValue = new JTextField("0", 3);

        //define the buttons to start and stop the timer
        startButton = new JButton("Start Timer");
        stopButton = new JButton("Stop Timer");

        //add the buttons to the action listener - so they fire an event when clicked
        startButton.addActionListener(this);
        stopButton.addActionListener(this);

        //add the buttons to the pane
        south.add(startButton);
        south.add(stopButton);

        //add all other objects to the pane
        center.add(hours);
        center.add(hourValue);
        center.add(minutes);
        center.add(minuteValue);
        center.add(seconds);
        center.add(secondValue);

        //create a timer that fires an event every second (1000 milliseconds)
        theTimer = new Timer(1000, this);
    }

    //defines the method which is called when an event is fired
    public void actionPerformed(ActionEvent e)
    {
        //capture the source which fired the event
        Object event = e.getSource();

        //define what to do when the start button is pushed
        if(event == startButton)
        {
            theTimer.start();
        }
        //define what to do when the stop button is pushed
        else if(event == stopButton)
        {
            theTimer.stop();
        }
        //define what to do when the timer fires the event (every 1000 milliseconds in this case)
        else if(event == theTimer)
        {
            addSecondValue();
        }
    }

    //define the method that increments the 'hours' section
    public void addHourValue()
    {
        theHour = hourValue.getText();
        int theHourValue = (Integer.parseInt(theHour)) + 1;

        hourValue.setText(Integer.toString(theHourValue));
    }

    //define the method that increments the 'minutes' section
    public void addMinuteValue()
    {
        theMinute = minuteValue.getText();
        String incrementedValue = increment(theMinute);

        minuteValue.setText(incrementedValue);

        if(incrementedValue.equals("0"))
            addHourValue();
    }

    //define the method that increments the 'seconds' section
    public void addSecondValue()
    {
        theSecond = secondValue.getText();
        String incrementedValue = increment(theSecond);

        secondValue.setText(incrementedValue);

        if(incrementedValue.equals("0"))
            addMinuteValue();
    }

    //define the method that increments the seconds and minutes, reseting the value to '0' every 60 occurances
    public String increment(String value)
    {
        int theValue = Integer.parseInt(value);

        if(theValue <= 58)
            theValue++;
        else
            theValue = 0;

        return Integer.toString(theValue);
    }
} 


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And here is the ZIP file that contains the HTML file and the CLASS file so that you can view it (the JAVA file is there aswell - the source code). Just open it in any java-enabled browser and it should work fine. Any questions just reply and I'll be happy to help.

EDIT: OK, so the ZIP file is attached in my post below (2 posts down).

Cheers,
Greg

Umm, Dude... Theres no ZIP file :confused:

ut oh were did the zip go?

Yeah...I know. I actually didn't mean to post it yet. I clicked 'Preview Post' and it posted it...so I'm just trying to figure out whether this 'Preview Post' button is working or if it's a BUG!!??

I edited twice, trying to add the zip...still not working. I'm not sure if it's just me or it's a bug with the site. Give us a few mins...

EDIT: OK, the 'Preview Post' is working fine...I dunno, I swear I thought I hit it and it posted it...aw well, maybe I'm going crazy.

Greg

OK, well, just using this app before, I had to reset each digit to "0" every quarter, so I figured I'd just chuck in a 'reset button'. So...I did and it's all sweet.

I'm not gonna post it here, but was thinking, if you are really trying to learn java and are actually taking a look at this, add a reset button that resets each figure to "0". You gotta basically create another button object, add it to the pane, add the action listener and then define the event. If you want to be more fancy, disable the button when the timer is active and enable it when the timer has stoped - that only takes two lines of code - use the 'setEnabled(boolean variable)' method.

And if you got any queries, just post em up.

Greg