JUnit testing

[Ale Gracia]

public class MyDate implements Serializable {
	private int second;
	private int minute;
	private int hour;
	private int day;
	private int month;
	private int year;

	public MyDate(int second, int minute, int hour, int day, int month, int year) {
		this.second = second;
		this.minute = minute;
		this.hour = hour;
		this.day = day;
		this.month = month;
		this.year = year;

	}

	public static MyDate getCurrentTime() {
		GregorianCalendar gc = new GregorianCalendar();
		return new MyDate(gc.get(Calendar.SECOND), gc.get(Calendar.MINUTE), gc.get(Calendar.HOUR),
				gc.get(Calendar.DAY_OF_MONTH), gc.get(Calendar.MONTH), gc.get(Calendar.YEAR));
	}

	public int getSecond() {
		return second;
	}

	public void setSecond(int second) {
		this.second = second;
	}

	public int getMinute() {
		return minute;
	}

	public void setMinute(int minute) {
		this.minute = minute;
	}

	public int getHour() {
		return hour;
	}

	public void setHour(int hour) {
		this.hour = hour;
	}

	public int getDay() {
		return day;
	}

	public void setDay(int day) {
		this.day = day;
	}

	public int getMonth() {
		return month;
	}

	public void setMonth(int month) {
		this.month = month;
	}

	public int getYear() {
		return year;
	}

	public void setYear(int year) {
		this.year = year;
	}

	public String toString() {
		return year + "-" + month + "-" + day + " " + hour + ":" + minute + ":" + second;
	}

	/**
	 * parses a String argument and returns a MyDate object, where the string should
	 * be formatted as following "yyyy-mm-dd hh:mm:ss"
	 * 
	 * @param sDate
	 *            of type String
	 * @return MyDate object.
	 */
	public static MyDate parse(String sDate) {
		String sYear = "";
		for (int i = 0; i < 4; i++) {
			sYear += sDate.charAt(i);
		}
		String sMonth = sDate.charAt(5) + "" + sDate.charAt(6);
		String sDay = sDate.charAt(8) + "" + sDate.charAt(9);
		String sHour = sDate.charAt(11) + "" + sDate.charAt(12);
		String sMinute = sDate.charAt(14) + "" + sDate.charAt(15);
		String sSecond = sDate.charAt(17) + "" + sDate.charAt(18);
		MyDate date = new MyDate(Integer.parseInt(sSecond), Integer.parseInt(sMinute), Integer.parseInt(sHour),
				Integer.parseInt(sDay), Integer.parseInt(sMonth), Integer.parseInt(sYear));
		return date;
	}

	public boolean isBefore(MyDate date2) {
		if (year < date2.getYear()) {
			return true;
		} else if (year > date2.getYear()) {
			return false;
		} else if (month < date2.getMonth()) {
			return true;
		} else if (month > date2.getMonth()) {
			return false;
		} else {
			if (day < date2.getDay()) {
				return true;
			} else if (day > date2.getDay()) {
				return false;
			} else {
				if (hour < date2.getHour()) {
					return true;
				} else if (hour > date2.getHour()) {
					return false;
				} else {
					if (minute < date2.getMinute()) {
						return true;
					} else if (minute > date2.getMinute()) {
						return false;
					} else
						return true;

				}
			}
		}

	}

}

Can someone help me with JUnit test, I've read the documentation about it but still don't get  how to test it? Thank you.

[Campbell Ritchie]

Before you test that code, stop using Calendar or the buillt‑in Date class. Use the newer classes as described in the Java™ Tutorials.

[Paul Clapham]

Campbell Ritchie wrote:Before you test that code, stop using Calendar or the buillt‑in Date class. Use the newer classes as described in the Java™ Tutorials.

It looks like the whole point of the code is to write a class which represents time-stamps. Yes, I know that's a WTF and it's the exact opposite of best practice. But apparently there are still some teachers who think it's a good way to practice coding.

[Knute Snortum]

Asking how to do JUnit testing is a little like asking how to program: it's a complex issue.  Can you give us some more context?  Have you been told to "add testing" to your program by a teacher or employer?  Is this for your own research?  Are you using an IDE?  Which one?  Are you using Maven?  Gradle?  Is this for a company that runs CI (continuous integration)?  In other words, is this part of a larger software development system or just for you?

After we determine your development environment, you would start writing unit tests.  This is a new program that will run your tests for the original program.  (You actually test methods).  I would start with very simple tests and build from there.

A JUnit tutorial would be a good place to start.  I would start by googling junit 5 tutorial for beginners.  Sorry, I can't recommend any specific one; I'm not familiar with them.  

[Campbell Ritchie]

I resisted the temptation to say that writing your own date/time classes is a waste of time, but at least it would have ben easier with a well‑designed class underlying that.

Of course, you should be able to extract the information without using an intermediate class at all, so I tried something on JShell:

String.format("%tY %1$tm %1$Td %1$TH:%1$TM:%1$TS.%1$TL", System.currentTimeMillis())
$5 ==> "2018 12 18 15:26:49.074"