calling a void method java

1public class MyClass {
2 
3    void myMethod() {
4        System.out.println("You have called me! My name is: myMethod!");
5    }
6 
7    public static void main(String[] args) {
8        new MyClass().myMethod();
9    }
10}
11

1public class methods{
2  public static void main(String[] args){
3    printSum(5, 15); // Print 20
4  }
5  public static void printSum(int a, int b){
6    System.out.println(a + b);
7  }
8  // Our method should be outside the main methods bounds
9  // Call your function inside the main method.
10}

1public class Main {
2  public static void main(String args[]) {
3    SayHi();
4    
5    int sum = AddNums(5, 6);
6    System.out.println(sum);
7  }
8  
9  public static void SayHi() { //This method has no return value
10    System.out.println("Hi!");
11  }
12  
13  public static int AddNums(int a, int b) { //This method has a return value
14    return a + b;
15}

1int a = 20;
2int b = 20;
3public static void sum(){ // Void Method
4  System.out.println(a + b);
5}
6public static int sum(){ // Return Function
7  return a + b;
8}