Merge remote-tracking branch 'origin/Demo' into Demo

src/main/java/com/example/helloWorld.java

@@ -3,5 +3,7 @@ package com.example;
 public class helloWorld {
     public static void main(String[] args) {
         System.out.println("Hello world!");
+        System.out.println("Hello world!");
     }
+
 }