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Lab 4: Time Class

Objective

To get more practice writing classes with constructors and methods in Java

Task

For this lab, you will create a class called "Time" that will allow us to store and work with time objects.

Your class should contain the following:

Private instance variables for storing the hours, minutes, and seconds. The hours will be in 24-hour format (e.g. 17 is 5:00 PM).
A default constructor that sets the time to midnight.
A constructor that takes hours, minutes and seconds as parameters.
A method called "increment" that takes a number of seconds as a parameter, and increases the time by that many seconds (you may have to increase the hour and minute as well).
A method called "print" that takes one parameter, a boolean called "military". If military is true, you should print the time in 24-hour format, otherwise print in the 12-hour AM/PM format.

You are just writing the Time class for this lab. To test your class, you can use this main class:


public class Main {
    public static void main(String args[]) {
        Time t1 = new Time();              // midnight
        Time t2 = new Time(17, 30, 0);     // 5:30 PM

        // add an hour onto t1, then print it in both formats
        t1.increment(3600);
        t1.print(true);
        t1.print(false);

        // add an hour and a half, and 30 seconds onto t2
        t2.increment(5430);

        // print t2 in both formats
        t2.print(true);
        t2.print(false);

    }
}

The goal output is given below:

1:00:00
1:00:00 AM
19:00:30
7:00:30 PM

Submitting

When you are done, please submit the Java code under the assignment in Canvas.

You only need to submit the Time.java file, not the Main.java one.

Solution

A solution to this lab can be found in Time.java.