Cviceni3.java

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class Cviceni3 {
	Calendar birth = Calendar.getInstance ();		// contains date of birth
	Calendar today = Calendar.getInstance ();		// contains today's date
	Calendar thisYear = Calendar.getInstance ();	// contains date of birthday on this year
	Date date;

	public Cviceni3 (Calendar calendar) {
		setDate (new Date (calendar.getTimeInMillis ()));
		initializeCalendars ();
	}

	public Cviceni3 (Date date) {
		setDate (date);
		initializeCalendars ();
	}

	public Cviceni3 (String string) {
		DateFormat format = new SimpleDateFormat ("d. M. yyyy");

		try {
			setDate (format.parse (string));
			initializeCalendars ();
		} catch (ParseException e) {
			System.out.println ("Spatny format data!");
		}
	}

	private void initializeCalendars () {
		birth.setTime (date);
		thisYear.setTime (date);
		thisYear.set (Calendar.YEAR, today.get (Calendar.YEAR));
	}

	private void setDate (Date date) {
		this.date = date;
	}

	public int getWeekDay () {
		return (birth.get (Calendar.DAY_OF_WEEK));
	}

	public int getAge () {
		int year1, year2, age;
		int month1, month2;
		int day1, day2;

		year1 = today.get (Calendar.YEAR);
		year2 = birth.get (Calendar.YEAR);
		age = year1 - year2;

		month1 = today.get (Calendar.MONTH);
		month2 = birth.get (Calendar.MONTH);

		if (month2 > month1) {
			age--;
		} else if (month1 == month2) {
			day1 = today.get (Calendar.DAY_OF_MONTH);
			day2 = birth.get (Calendar.DAY_OF_MONTH);

			if (day2 > day1) {
				age--;
			}
		}

		return (age);
	}

	public int getThisYearWeekDay () {
		return (thisYear.get (Calendar.DAY_OF_WEEK));
	}
}

Cviceni3Test.java

import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.util.Calendar;
import java.util.Date;

import static junit.framework.Assert.assertEquals;

public class Cviceni3Test {
	private Calendar calendar = Calendar.getInstance ();
	private Cviceni3 instance1, instance2, instance3;
	private Date date = new Date (615636000000l);
	private String string = "5. 7. 1989";

	@Before
	public void setUp () throws Exception {
		calendar.set (Calendar.YEAR, 1989);
		calendar.set (Calendar.MONTH, Calendar.JULY);
		calendar.set (Calendar.DAY_OF_MONTH, 5);

		instance1 = new Cviceni3 (calendar);
		instance2 = new Cviceni3 (date);
		instance3 = new Cviceni3 (string);
	}

	@After
	public void tearDown () throws Exception {
		instance1 = null;
		instance2 = null;
		instance3 = null;
	}

	@Test
	public void testConstructors () throws Exception {
		assertEquals (4, instance1.getWeekDay ());
		assertEquals (4, instance2.getWeekDay ());
		assertEquals (4, instance3.getWeekDay ());
	}

	@Test
	public void testGetWeekDay () throws Exception {
		assertEquals (4, instance3.getWeekDay ());
	}

	@Test
	public void testAge () throws Exception {
		assertEquals (21, instance3.getAge ());
	}

	@Test
	public void testGetThisYearWeekDay () throws Exception {
		assertEquals (3, instance3.getThisYearWeekDay ());
	}
}