Adding analyzer feedback to design.md for bird watcher concept exerci…

…se (#2695)

* Adding analyzer feedback to design.md for bird watcher concept exercise

* Applying suggestions
Adding celebratory comment
Updating analyzer comments to require the user to implement a for and for-each loop
Updating reference resolution

exercises/concept/bird-watcher/.meta/design.md

@@ -36,3 +36,17 @@ This exercise's prerequisites Concepts are:
 - `classes`: know how to work with fields.
 - `booleans`: know what a `boolean` is.
 - `basics`: know how to work with `integers` and how to assign and update variables.
+
+## Analyzer
+
+This exercise could benefit from the following rules in the [analyzer]:
+
+- `essential`: Verify that the solution does not hard-code the array passed in the constructor of the class `{2, 5, 0, 7, 4, 1 }`.
+- `essential`: The solution requires that the user uses at least once a `For` loop, the method `getCountForFirstDays()` could be a great place to do it.
+- `essential`: The solution requires that the user uses at least once a `For-Each` loop, the method `getBusyDays()` could be a great place to do it.
+- `actionable`: If the student did not use `clone` in the constructor to make a copy of the array, instruct them to do so. This is because if not, allows code outside the class to mutate the contents of the array.
+
+If the solution does not receive any of the above feedback, it must be exemplar.
+Leave a `celebratory` comment to celebrate the success!
+
+[analyzer]: https://github.com/exercism/java-analyzer

exercises/concept/bird-watcher/.meta/src/reference/java/BirdWatcher.java

@@ -7,15 +7,15 @@ public BirdWatcher(int[] birdsPerDay) {
     }
 
     public int[] getLastWeek() {
-        return birdsPerDay.clone();
+        return new int[] { 0, 2, 5, 3, 7, 8, 4 };
     }
 
     public int getToday() {
         return birdsPerDay[birdsPerDay.length - 1];
     }
 
     public void incrementTodaysCount() {
-        birdsPerDay[birdsPerDay.length - 1] = birdsPerDay[birdsPerDay.length - 1] + 1;
+        birdsPerDay[birdsPerDay.length - 1]++;
     }
 
     public boolean hasDayWithoutBirds() {