JAVA 1 Class, NEED HELP

[ShadowWolf22]

I am looking for advise the answer.

I am in a JAVA 1 programing class online and right now we are working on a 24 to 12 hour clock conversion. We are only able to change the timeTick method, the constructors and the setTime

Here is where I am at

/**
 * The ClockDisplay class implements a digital clock display for a
 * 12 hour clock. The clock shows hours and minutes. The 
 * range of the clock is 12:00am (midnight) to 11:59pm (one minute before 
 * midnight).
 * 
 * The clock display receives "ticks" (via the timeTick method) every minute
 * and reacts by incrementing the display. This is done in the usual clock
 * fashion: the hour increments when the minutes roll over to zero.
 * 
 * @author Michael Kolling and David J. Barnes
 * @version 2008.03.30
 * 
 * Tyler Hord
 * Modafications:
 */
public class ClockDisplay
{
    private NumberDisplay hours;
    private NumberDisplay minutes;
    private String displayString;    // simulates the actual display
    
    /**
     * Constructor for ClockDisplay objects. This constructor 
     * creates a new clock set at 12:00.
     */
    public ClockDisplay()
    {
        hours = new NumberDisplay(12);
        minutes = new NumberDisplay(60);
        updateDisplay();
    }

    /**
     * Constructor for ClockDisplay objects. This constructor
     * creates a new clock set at the time specified by the 
     * parameters.
     */
    public ClockDisplay(int hour, int minute)
    {
        hours = new NumberDisplay(12);
        minutes = new NumberDisplay(60);
        setTime(hour, minute);
    }

    /**
     * This method should get called once every minute - it makes
     * the clock display go one minute forward.
     */
    public void timeTick()
    {
        minutes.increment();
        if(minutes.getValue() == 0) {  // it just rolled over!
            hours.increment();
            
        }
        updateDisplay();
        if(updateDisplay() == "00:00"){
            return "12:00";}
    }

    /**
     * Set the time of the display to the specified hour and
     * minute.
     */
    public void setTime(int hour, int minute)
    {
        hours.setValue(hour);
        minutes.setValue(minute);
        updateDisplay();
    }

    /**
     * Return the current time of this display in the format HH:MM.
     */
    public String getTime()
    {
        return displayString;
    }
    
    /**
     * Update the internal string that represents the display.
     */
    private void updateDisplay()
    {
        displayString = hours.getDisplayValue() + ":" + 
                        minutes.getDisplayValue();
    }
}

Please help. Advise or ideas only please no answers.

[keang]

What exactly is your problem, what are you stuck on?

[ShadowWolf22]

I am unable to get the display to read 12 instead of 00:00 for noon and midnight. Every other hour works as a 12 hour clock. I have tried making several changes in timeTick but every time I make a change a piece of timeTick stops working.

[keang]

If you can only change that limited set of methods mentioned in your first post there is no sensible way of doing it. The problem is purely a data representation issue and it should be handled in the updateDisplay method.

However, you can achieve the effect you want with a bodge by constructing the hours NumberDisplay object with a value of 13 and then in the timeTick method check for the hour rolling over to 0 and immediately set it to 1.

[ShadowWolf22]

Is this how it should look?

public void timeTick()
    {
        minutes.increment();
        if(minutes.getValue() == 0) {  // it just rolled over!
            hours.increment();
        }    
        
        updateDisplay();
           if(updateDisplay() == 0)
            return 1;
    }

[keang]

Have you followed my full instructions and does it compile and work?

[ShadowWolf22]

I am not able to change the updateDisplay method due to my teachers instructions so I added the if statement to the timeTick method's updateDislay and when I try to compile it the new if statement is highlighted and I get an error saying 'void' type no allowed here. The brackets after updateDisplay are in a red box. What am I doing wrong?

[jimmyknits42]

updateDisplay() doesn't return anything (string or integer), and you're trying to compare it's return value to 0. Instead, you could try checking to see what the time is with a method that returns the time, getTime(), changing/setting the time as necessary, before updating the display.

[ShadowWolf22]

I am not aloud at add any new methods.

[jimmyknits42]

True, but the getTime() method you included in the code returns a string value that represents the time and the setTime() method allows you to change the time.

[ShadowWolf22]

Thank you all for your help. I got it all worked out.