clock.java

java编的售糖程序

//class Clock

public class Clock
{
    private int hr;  //store hours
    private int min; //store minutes
    private int sec; //store seconds

        //Constructor with parameters, to set the time
        //The time is set according to the parameters
        //Postcondition: hr = hours; min = minutes; sec = seconds
    public Clock(int hours, int minutes, int seconds)
    {
        setTime(hours, minutes, seconds);
    }
    
        //Default constructor
        //Postcondition: hr = 0; min = 0; sec = 0
    public Clock()
    {
        setTime(0, 0, 0);
    }

        //Method to set the time
        //The time is set according to the parameters
        //Postconditions: hr = hours; min = minutes; sec = seconds
    public void setTime(int hours, int minutes, int seconds)
    {
        if(0 <= hours && hours < 24)
            hr = hours;
        else
            hr = 0;

        if(0 <= minutes && minutes < 60)
            min = minutes;
        else
            min = 0;

        if(0 <= seconds && seconds < 60)
            sec = seconds;
        else
            sec = 0;
    }

        //Method to return the hours
        //Postconditions: the value of hr is returned
    public int getHours()
    {
        return hr;
    }

        //Method to return the minutes
        //Postconditions: the value of min is returned
    public int getMinutes()
    {
        return min;
    }

        //Method to return the seconds
        //Postconditions: the value of sec is returned
    public int getSeconds()
    {
        return sec;
    }

        //Method to print the time
        //Postconditions: Time is printed in the form hh:mm:ss
    public void printTime()
    {
        if(hr < 10)
            System.out.print("0");
        System.out.print(hr + ":");

        if(min < 10)
            System.out.print("0");
        System.out.print(min + ":");

        if(sec < 10)
            System.out.print("0");
        System.out.print(sec);
    }

        //Method to increment the time by one second
        //Postconditions: The time is incremented by one second
        //If the before-increment time is 23:59:59, the time
        //is reset to 00:00:00
    public void incrementSeconds()
    {
        sec++;
        if(sec > 59)
        {
            sec = 0;
            incrementMinutes(); //increment minutes
        }
    }

        //Method to increment the time by one minute
        //Postconditions: The time is incremented by one minute
        //If the before-increment time is 23:59:53, the time
        //is reset to 00:00:53
    public void incrementMinutes()
    {
        min++;
        if(min > 59)
        {
            min = 0;
            incrementHours(); //increment hours
        }
    }

        //Method to increment the time by one hour
        //Postconditions: The time is incremented by one hour
        //If the before-increment time is 23:45:53, the time
        //is reset to 00:45:53
    public void incrementHours()
    {
        hr++;
        if(hr > 23)
            hr = 0;
    }

        //Method to compare the two times
        //Postconditions: Returns true if this time is equal to
        //                otherTime; otherwise returns false
    public boolean equals(Clock otherClock)
    {
        return(hr == otherClock.hr
                && min == otherClock.min
                && sec == otherClock.sec);
    }
    
        //Method to copy time
        //Postcondition: The data members of otherTime are copied
        //               into the correspoding data members of
        //               this time.
        //               hr = otherTime.hr; min = otherTime.min;
        //               sec = otherTime.sec;
    public void makeCopy(Clock otherClock)
    {
        hr = otherClock.hr;
        min = otherClock.min;
        sec = otherClock.sec;
    }

        //Method to return a copy of time
        //Postcondition: A copy of the object is created
        //               and a reference of the copy is returned
    public Clock getCopy()
    {
        Clock temp = new Clock();

        temp.hr = hr;
        temp.min = min;
        temp.sec = sec;

        return temp;
    }

    public String toString()
    {
        String str = "";

        if(hr < 10)
            str = "0";
        str = str + hr + ":";

        if(min < 10)
            str = str + "0" ;
        str = str + min + ":";

        if(sec < 10)
            str = str + "0";
        str = str + sec;

        return str;
    }
}