class in java

1public class Lightsaber {
2  // properties
3  private boolean isOn;
4  private Color color;
5  
6  // constructor
7  public Lightsaber(Color color) {
8    this.isOn = false;
9    this.color = color;
10  }
11  
12  // getters
13  public Color getColor() {
14    return color;
15  }
16  public boolean getOnStatus() {
17    return isOn;
18  }
19  
20  // setters
21  public void turnOn() {
22    isOn = true;
23  }
24  public void turnOff() {
25    isOn = false;
26  }
27}
28
29
30
31// Implementation in main method:
32public class test {
33  public static void main(String[] args) {
34    Lightsaber yoda = new Lightsaber(green);
35    yoda.turnOn();
36  }
37}
38    

1// this might help you understand how classes work
2public class MathTest {
3
4    public static void main(String[] args) {
5
6        class MathAdd {
7
8            int num1;
9            int num2;
10
11            public int addNumbers() {
12
13                int addThemUp = num1 + num2;
14                return addThemUp;
15            }
16        }
17
18        MathAdd addition = new MathAdd(); // create a new instance of the class
19
20        // you can access variables from the class 
21        addition.num1 = 10; 
22        addition.num2 = 20;
23
24        // and use the method from the class to add them up
25        System.out.println(addition.addNumbers());
26
27    }
28}

1
2public class HelloWorld {
3  public static void main(String[] args) {
4    
5    // how to use class in java
6    class User{
7    	
8    	int score;
9    }
10    
11    User dave = new User();
12    
13    dave.score = 20;
14    
15    System.out.println(dave.score);
16    
17 
18  }
19}
20

1Class is a blueprint or template which
2you can create as many objects as you 
3like. Object is a member or instance
4of a class.
5Class is declared using class keyword,
6Object is created through
7new keyword mainly. A class is a template
8  for objects. A class defines 
9object properties including a valid range
10    of values, and a default value. 
11A class also describes object behavior.

1//	Example : TestClass (Can be predefined or user-defined)
2public class TestClass {
3  // properties
4  private int id = 111;
5  
6  // constructor
7  public TestClass(){
8    super();
9  }
10  
11  // method
12  public void test(){
13    // some code here
14  }
15}

1class Number {
2    	
3    	int number;
4    	
5    	// square numbers
6    	public boolean isSquare(){
7    		
8    		double squareRoot = Math.sqrt(number);
9    		
10    		
11    		if(squareRoot == Math.floor(squareRoot))
12    		{
13    			return true;
14    		} else {
15    			return false;
16    		}
17    		
18    	}
19    	
20    	// triangular numbers
21    	public boolean isTriangular(){
22    		
23    		int x = 1;
24    		
25    		int triangularNumber = 1;
26    		
27    		while(triangularNumber < number){
28    			
29    			x++;
30    			triangularNumber = triangularNumber + x;
31    			
32    		}
33    		
34    		if(triangularNumber == number){
35    			return true;
36    		} else {
37    			return false;
38    		}
39    	}
40    }
41    
42    // testing 
43    Number myNumber = new Number();
44    myNumber.number = 16;
45    
46    System.out.println(myNumber.isSquare());