using class in java

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 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());

1public class HelloWorld {
2  public static void main(String[] args) {
3   
4   
5   class Number{
6   
7   	int number;
8   
9   	public boolean isPos(){
10   		if(number > 0){
11   			return true;
12   		} else {
13   			return false;
14   		}
15   		
16   	}
17   }
18   
19   Number myNumber = new Number();
20   
21   myNumber.number = 7;
22   
23   if(myNumber.isPos()){
24   	System.out.println(myNumber.number + " is positive!!!");
25   } else {
26   	System.out.println(myNumber.number + " is not positive!!!");
27   }
28   
29  }
30}
31

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    	// method that can be used outside the class
11    	public boolean hasWon(){
12    		if(score >= 100){
13    			return true;
14    		} else {
15    			return false;
16    		}
17    	}
18    }
19    
20    User dave = new User();
21    
22    dave.score = 20;
23    
24    System.out.println(dave.hasWon());
25    
26 
27  }
28}
29