cleanup work in guava tests

guava/src/test/java/org/baeldung/guava/GuavaCollectionTypesTest.java

@@ -111,8 +111,10 @@ public class GuavaCollectionTypesTest {
         assertThat(immutable, contains("John", "Adam", "Jane", "Tom"));
     }
 
+    // sets
+
     @Test
-    public void whenCalculateUnion_thenCorrect() {
+    public void whenCalculateUnionOfSets_thenCorrect() {
         final Set<Character> first = ImmutableSet.of('a', 'b', 'c');
         final Set<Character> second = ImmutableSet.of('b', 'c', 'd');
 
@@ -120,15 +122,6 @@ public class GuavaCollectionTypesTest {
         assertThat(union, containsInAnyOrder('a', 'b', 'c', 'd'));
     }
 
-    @Test
-    public void whenCalculateIntersection_thenCorrect() {
-        final Set<Character> first = ImmutableSet.of('a', 'b', 'c');
-        final Set<Character> second = ImmutableSet.of('b', 'c', 'd');
-
-        final Set<Character> intersection = Sets.intersection(first, second);
-        assertThat(intersection, containsInAnyOrder('b', 'c'));
-    }
-
     @Test
     public void whenCalculateSetsProduct_thenCorrect() {
         final Set<Character> first = ImmutableSet.of('a', 'b');
@@ -146,6 +139,15 @@ public class GuavaCollectionTypesTest {
         assertThat(joined, containsInAnyOrder("a c", "a d", "b c", "b d"));
     }
 
+    @Test
+    public void whenCalculatingSetIntersection_thenCorrect() {
+        final Set<Character> first = ImmutableSet.of('a', 'b', 'c');
+        final Set<Character> second = ImmutableSet.of('b', 'c', 'd');
+
+        final Set<Character> intersection = Sets.intersection(first, second);
+        assertThat(intersection, containsInAnyOrder('b', 'c'));
+    }
+
     @Test
     public void whenCalculatePowerSet_thenCorrect() {
         final Set<Character> chars = ImmutableSet.of('a', 'b');