Additional test.

P/Sda1/Javastreams/src/test/java/de/hdm_stuttgart/mi/javastreams/FunctionalTests.java

@@ -13,12 +13,46 @@ import org.junit.Test;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 
+import de.hdm_stuttgart.mi.javastreams.Student.Sex;
+
 /**
  * Testing functional queries.
  */
 public class FunctionalTests {
 
    final List<Student> roster = Student.createRoster();
+   
+   /**
+    * Order all male students by email and create a list of their respective names
+    * in that order eliminating possible duplicates:
+    * 
+    *  "Bob", 2, Student.Sex.MALE, "bob@uk.edu"
+    *  "Fred", 2, Student.Sex.MALE, "fred@example.com"
+    *  "George", 4, Student.Sex.MALE, "george@math.edu"
+    *  "Jane", 1, Student.Sex.FEMALE, "jane@kiv.de"
+    *  "Kim", 2, Student.Sex.FEMALE, "wilde@serious.de"
+    *  
+    *  ==> {"Bob", "Fred", "George"}
+    *  
+    */
+   @Test
+   public void allMaleDistinctNameOrderedByEmail() {
+      
+      List<String> emails =
+            roster.
+            stream().
+            filter(s -> s.gender == Sex.MALE).
+            sorted((s1, s2) -> s1.getEmailAddress().compareTo(s2.getEmailAddress())).
+            map(Student::getName).
+            distinct().
+            collect(Collectors.toList());
+      
+      assertThat(emails,
+            Matchers.<List<String>> equalTo( 
+                  ImmutableList.of("Bob", "Fred", "George") 
+                  ) 
+            );
+   }
 
    /**
     * Summing students' marks having a German email address:
@@ -38,7 +72,6 @@ public class FunctionalTests {
             );
    }
 
-
    /**
     * Group students by sex and collect their respective names:
     *