ArrayList<String> list = new ArrayList<>();

Week 3: Objects, files and exceptions/6a. Objects as return values

@@ -0,0 +1,64 @@
+It is often better practice to CREATE a NEW OBJECT and RETURN it from the method.
+In this case, the original object is not changed.
+
+The normal way to return an object is with a return statement. 
+On the calling method side, the return value must of course be stored in a variable if it is to be used later in the program.
+
+import java.util.ArrayList;
+
+public class Example {
+    public static void main(String[] parameters){
+        ArrayList<Integer> numbers = new ArrayList<>();
+        numbers.add(5);
+        numbers.add(1);
+        numbers.add(8);
+
+        System.out.println("List before: " + numbers);
+        System.out.println("New list: " + increasebyOne(numbers));
+        System.out.println("List after: " + numbers);   
+    }
+
+    public static ArrayList<Integer> increasebyOne(ArrayList<Integer> numbers) {
+        ArrayList<Integer> newList = new ArrayList<>();
+        for (int element : numbers) {
+            newList.add(element + 1);
+        }
+        return newList;
+    }
+}
+
+Program outputs:
+List before: [5, 1, 8]
+New list: [6, 2, 9]
+List after: [5, 1, 8]
+ 
+
+====================================================================
+
+
+
+Of course, the method can also create an object from scratch, and return it.
+
+The example creates a NEW LIST with the number of EMPTY STRINGS specified by the given parameter:
+
+import java.util.ArrayList;
+
+public class Example {
+    public static void main(String[] parameters){
+        ArrayList<String> strings = createList(10);
+        System.out.println("List size:" + strings.size());  
+    }
+
+    public static ArrayList<String> createList(int size) {
+        ArrayList<String> list = new ArrayList<>();
+        for (int i=0; i<size; i++) {
+            list.add("");
+        }
+        return list;
+    }
+}
+
+Program outputs:
+List size: 10
+
+