Programming (EN)

[Java] Java methods with return value

2020-12-22

When Method is written using return in Java, data_type should be matched in 〇〇 area as below:

public static 〇〇 method_name(arguments) { 
        
}


When return value is int

Method should be written as 「public sttatic int method_name()」



import java.util.*;

public class Main {
      public static void main(String[] args) {
        int math = add(1, 10);
        System.out.println(math);

    }
    
    // When return value is int
    public static int add (int x, int y) {
        int math = x + y;
        
        return math;
    }
}


When return value is String

Method should be written as 「public static String method_name()」



import java.util.*;

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

        String hello = hello("Hello", "Mr/Ms ---");
        System.out.println(hello);
    }
    

    //When String is return value
    public static String hello (String x, String y) {
        String hello = x + " " + y;
        return hello;
    }
    
}


When return value is boolean

Method should be written as 「public static boolean method_name()」



import java.util.*;

public class Main {
      public static void main(String[] args) {
        Boolean math2 = math2();
        System.out.println(math2);
    }
    
    
    //When boolean is return value
    public static boolean math2() {
            int math2 = 10 / 5;
		        if (math2 == 0) {
			        return true;
		        }
		            return false;
            }

}


What does ”void” mean?

It's often shown as main function. What does void mean?

public static void main(String[] args) { 
        
}


Void is used when there are no return value.

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

-Programming (EN)