Objects of A, B, C
==================
class A {  public void reply() {System.out.println("Hi!");}  }

class B {  public void reply() {System.out.println("Hey!");}  }

class C {
	public void talkTo(A x) {System.out.println("Hi A object!"); x.reply();}

	public void talkTo(B x) {System.out.println("Hi B object!"); x.reply();}
}

public class Main {

	public static void main(String[] args) {
		A a = new A();
		B b = new B();
		C c = new C();
		c.talkTo(a);
		c.talkTo(b);		
	}
}


Redundant Object
================
public class Main {

	public static void main(String[] args) {
		//get values for int y, m, d from user
		int y=2014;
		int m=12;
		int d=31;

		Day d1 = new Day(y,m,d);
		Day d2 = new Day(y,m,d);
		d2 = d1.next(); //return the next day of d1
		System.out.println("Next of " + d1 + " is " + d2);
				
	}
}


Today is a good day
===================
import java.util.*;

public class Main {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		String s1,s2;
		s1 = in.next(); //type "   Today    is a good day."
		s2 = in.nextLine();
		System.out.println(s1); //"Today"
		System.out.println(s2); //"    is a good day“
		in.close();		
				
	}
}


Next year your age (given)
==================
import java.util.*;

public class Main {

	public static void main(String[] args) {

		String name;
		int age;


		System.out.print("What is your name? ");


		System.out.print("How old are you? ");


		System.out.println("Hello, " + _____ + ".  Next year, you will be " + ____);

		in.close();
	}

}

Next year your age
==================
import java.util.*;

public class Main {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		String name;
		int age;

		System.out.print("What is your name? ");
		name = in.nextLine();

		System.out.print("How old are you? ");
		age = in.nextInt();

		System.out.println("Hello, " + name + ".  Next year, you will be " + age + 1);
		System.out.println("Hello, " + name + ".  Next year, you will be " + (age + 1));
		in.close();
	}

}

Topic03 Page 1
===============
	public void advance() 
	{		
		if (isEndOfAMonth())
		{
			if (month==12)
			{
				year = __________;
				month = _________;
				day = ___________;
			}
			else
			{				
				
			}
		}
		else
		{
			
		}
	}	
------------------------
public class Main {

	public static void main(String[] args) {
		Day d1 = new Day(2014, 1, 28);
		System.out.println(d1.toString()); 	//Show 28 Jan 2014
		__.advance();	//Advance one day
		______.next(); 	//Advance one day
		System.out.println(d1.toString()); 	//Show 30 Jan 2014
	}
}



Employee and Hire day
=====================
class Employee {

	private final String name;
	private double salary;//=0;//= Math.random()*10000;
	private final Day hireDay;

	public Employee(String n, double s, int year, int month, int day)	{
		name = n; salary = s; hireDay = new Day(year,month,day);
	}

	public String getName() {return name;}
	public double getSalary() {return salary;}
	public Day getHireDay() {return hireDay;}

	public void raiseSalary(double percent) {
		double raise = salary * percent/100;
		salary += raise;
	}
}

public class Main {
	public static void main(String[] args)	{
		
		Employee[] staff = new Employee[3];
		staff[0] = new Employee("Carl Cracker", 75000, 1987, 12, 15);
		staff[1] = new Employee("Harry Hacker", 50000, 1989, 10, 1);
		staff[2] = new Employee("Tony Tester", 40000, 1990, 3, 15);

		for (Employee e : staff)
			e.raiseSalary(5);

		for (Employee e : staff)
			System.out.println(
					"name=" + e.getName() + 
					",salary=" + e.getSalary() + 
					",hireDay=" + e.getHireDay());
	}
}



Day: More Day constructors
==========================
/*
    public Day(int y) {
        // to be completed
    }

    public Day(int y, int nth_dayInYear) {
        // to be completed
    }
*/

public class Main {
    public static void main(String[] args) {
        Day d1;

        d1 = new Day(2014, 1, 28);
        System.out.println(d1); // 28 Jan 2014
        
        d1 = new Day(2018); // The first day in 2018
        System.out.println(d1); // 1 Jan 2018
        
        d1 = new Day(2014, 45); // The 45th day in 2014
        System.out.println(d1); // 14 Feb 2014
    }
}


birthday, deadline
==================

import java.util.*;

public class Main {

	public static void main(String[] args) {

		Day birthday, deadline;
		birthday = new Day(2014, 1, 15);
		deadline = birthday;

		System.out.println(birthday); // 15 Jan 2014
		System.out.println(deadline); // 15 Jan 2014

		birthday.advance();
		System.out.println(birthday); // 16 Jan 2014
		System.out.println(deadline); // ________________

		birthday.next();
		System.out.println(birthday); // ________________
		System.out.println(deadline); // ________________

		birthday = birthday.next();
		System.out.println(birthday); // ________________
		System.out.println(deadline); // ________________
	}
}



Topic03 Page 7 Variables and Objects - 3 tests
====================================
public class Main
{
	public static void main(String[] args)
	{
	//testing1
		// Day d1;	
		// System.out.println(d1); //Error: The local variable d1 may not have been initialized
		// System.out.println(d1.toString()); //Error: The local variable d1 may not have been initialized

	//testing2
		// Day d1;
		// d1=null;
		// System.out.println(d1); //print: null
		// System.out.println(d1.toString()); //Runtime exception: java.lang.NullPointerException
		// System.out.println(d1); //print: null
		// System.out.println(d1); //print: null
	
	//testing3
		// Day d1=new Day(2014,1,15);
		// System.out.println(d1); 
		// System.out.println(d1.toString()); 
   
	}
}