@@ -37,8 +37,8 @@
         <artifactId>maven-compiler-plugin</artifactId>
         <version>3.1</version>
         <configuration>
-          <source>1.9</source>
-          <target>1.9</target>
+          <source>1.8</source>
+          <target>1.8</target>
         </configuration>
       </plugin>
       <plugin>
 
@@ -12,10 +12,10 @@ public static void main(String... args) {
         System.out.println(max(empty(), of(5)));
 
         Optional<Integer> opt1 = of(5);
-        Optional<Integer> opt2 = opt1.or(() -> of(4));
+        Optional<Integer> opt2 = of(opt1.orElse(4));
 
         System.out.println(
-        of(5).or(() -> of(4))
+        of(5).orElse(4)
                           );
     }
 
 
@@ -13,7 +13,6 @@ enum CaloricLevel { DIET, NORMAL, FAT };
     public static void main(String ... args) {
         System.out.println("Dishes grouped by type: " + groupDishesByType());
         System.out.println("Dish names grouped by type: " + groupDishNamesByType());
-        System.out.println("Dish tags grouped by type: " + groupDishTagsByType());
         System.out.println("Caloric dishes grouped by type: " + groupCaloricDishesByType());
         System.out.println("Dishes grouped by caloric level: " + groupDishesByCaloricLevel());
         System.out.println("Dishes grouped by type and caloric level: " + groupDishedByTypeAndCaloricLevel());
@@ -32,13 +31,8 @@ private static Map<Dish.Type, List<String>> groupDishNamesByType() {
         return menu.stream().collect(groupingBy(Dish::getType, mapping(Dish::getName, toList())));
     }
 
-    private static Map<Dish.Type, Set<String>> groupDishTagsByType() {
-        return menu.stream().collect(groupingBy(Dish::getType, flatMapping(dish -> dishTags.get( dish.getName() ).stream(), toSet())));
-    }
-
     private static Map<Dish.Type, List<Dish>> groupCaloricDishesByType() {
-//        return menu.stream().filter(dish -> dish.getCalories() > 500).collect(groupingBy(Dish::getType));
-        return menu.stream().collect(groupingBy(Dish::getType, filtering(dish -> dish.getCalories() > 500, toList())));
+        return menu.stream().filter(dish -> dish.getCalories() > 500).collect(groupingBy(Dish::getType));
     }
 
     private static Map<CaloricLevel, List<Dish>> groupDishesByCaloricLevel() {
 
@@ -32,10 +32,10 @@ public static Map<Boolean, List<Integer>> partitionPrimesWithCustomCollector(int
 
     public static boolean isPrime(List<Integer> primes, Integer candidate) {
         double candidateRoot = Math.sqrt((double) candidate);
-        //return takeWhile(primes, i -> i <= candidateRoot).stream().noneMatch(i -> candidate % i == 0);
-        return primes.stream().takeWhile(i -> i <= candidateRoot).noneMatch(i -> candidate % i == 0);
+        return takeWhile(primes, i -> i <= candidateRoot).stream().noneMatch(i -> candidate % i == 0);
+//        return primes.stream().takeWhile(i -> i <= candidateRoot).noneMatch(i -> candidate % i == 0);
     }
-/*
+
     public static <A> List<A> takeWhile(List<A> list, Predicate<A> p) {
         int i = 0;
         for (A item : list) {
@@ -46,7 +46,7 @@ public static <A> List<A> takeWhile(List<A> list, Predicate<A> p) {
         }
         return list;
     }
-*/
+
     public static class PrimeNumbersCollector
             implements Collector<Integer, Map<Boolean, List<Integer>>, Map<Boolean, List<Integer>>> {