java class and object example

Example 1: how to make a class in java

public class Main {
 public static void main (String[] args) {
	System.out.println("Hello World");
 } 
}

Example 2: using class in java

public class HelloWorld {
  public static void main(String[] args) {
   
   
   class Number{
   
   	int number;
   
   	public boolean isPos(){
   		if(number > 0){
   			return true;
   		} else {
   			return false;
   		}
   		
   	}
   }
   
   Number myNumber = new Number();
   
   myNumber.number = 7;
   
   if(myNumber.isPos()){
   	System.out.println(myNumber.number + " is positive!!!");
   } else {
   	System.out.println(myNumber.number + " is not positive!!!");
   }
   
  }
}

Example 3: using class in java

public class HelloWorld {
  public static void main(String[] args) {
    
    // how to use class in java
    class User{
    	
    	int score;
    	
    	// method that can be used outside the class
    	public boolean hasWon(){
    		if(score >= 100){
    			return true;
    		} else {
    			return false;
    		}
    	}
    }
    
    User dave = new User();
    
    dave.score = 20;
    
    System.out.println(dave.hasWon());
    
 
  }
}