Lectures / Lecture1Optional

import java.util.Scanner;


// class - abstract data type
// object - instance of the class

// access modifiers: public, private, protected 
class Human {
	
	// variable
	// local
	// class
	
	// methods
	//constructor


	
	// instance variables
	private int age;
	private String name;
	
	static int number;
	
	//default constructor
	public Human(){}
	public Human(){
		this.age = 0;
		this.name = "";
	}
	// parametrized constructor
	public Human(int age){
		this.age = age;
	}
	// fully-parametrized constructor
	public Human(int age, String name){
		this.age = age;
		this.name = name;
	}
	
	// create getter/setter methods for each instance variable
	// getter
	public int getAge() {
		return age;
	}
	// setter
	public void setAge(int age) {
		this.age = age;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	// you may add any methods inside the class
	public void sayHello(){
		System.out.println("Hello");
	}
	
	// main method
	public static void main(String args[]){
		
		int x; // statement
		int v; // declaration
		int y = 10; // initialization
		
		Human human;//reference
		Human human1 = new Human(); // object
		Human human2 = new Human(22,"Ed");
		Human human3 = new Human(24,"Ann");
		
		// streams in java
		// cout = System.out
		// cin = System.in 
		
		Scanner sc = new Scanner(System.in);
		System.out.println("Enter name, then age");
		String name = sc.nextLine();
		int age = sc.nextInt();
		
		// we can get acces to the private variables only
		// through the public methods 
		human1.name = name;
		human1.setAge(age);
		//human1.age = 10; - error, because age is private
		
		human3 = human2;
		
		int x = 4;
		int y = x;
		x = 5;
		
	}

}