yeah :)

src/main/java/assertions/Person.java

@@ -22,4 +22,15 @@ public String getFullName(){
     public Period getAge(){
         return Period.between(birthDate, LocalDate.now());
     }
+
+    public Boolean isTeen(int years){
+        // Is teen if Age 12 <= && >=18
+        Period age = getAge();
+        years =  age.getYears();
+        if (years >= 12 && years <= 18){
+            return true;
+        }
+        return false;
+
+    }
 }

src/test/java/assertions/PersonTest.java

@@ -1,8 +1,10 @@
 package assertions;
 
+import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
 import java.time.LocalDate;
+import java.time.Period;
 
 class PersonTest {
 
@@ -11,28 +13,75 @@ class PersonTest {
     @Test
     void getFullNameReturnsFirstnameSpaceLastname(){
         // TODO implement
-        throw new IllegalArgumentException("you should implement code here");
+       // throw new IllegalArgumentException("you should implement code here");
+        Person pers1 = new Person("Tobias", "Meier", null);
+        Assertions.assertEquals("Tobias Meier",pers1.getFullName());
+
     }
 
     // TODO some more useful tests
+    @Test
+    void getFullNameCheckSpaceBetween(){
+        Person pers1 = new Person("Tobias", "Meier", null);
+        String fullName = pers1.getFullName();
+        Assertions.assertTrue(fullName.contains(" "), "True if space between firstname and lastname");
+    }
+
+    @Test
+    void isTeenAge18_12ReturnTrue(){
+        Person pers1 = new Person("", "", LocalDate.of(2003, 3,11));
+        Person pers2 = new Person("", "", LocalDate.of(2009, 3, 11));
+        Period age1 = pers1.getAge();
+        Period age2 = pers2.getAge();
+        int years1 = age1.getYears();
+        int years2 = age2.getYears();
+
+        Assertions.assertEquals(18, age1.getYears());
+        Assertions.assertEquals(12, age2.getYears());
+        Assertions.assertTrue(pers1.isTeen(years1),"Is teen = true");
+        Assertions.assertTrue(pers2.isTeen(years2),"Is teen = true");
+
+    }
+    @Test
+    void isNotTeenAge11_19ReturnFalse(){
+        Person pers1 = new Person("", "", LocalDate.of(2010, 3,11));
+        Person pers2 = new Person("", "", LocalDate.of(2002, 3, 11));
+        Period age1 = pers1.getAge();
+        Period age2 = pers2.getAge();
+        int years1 = age1.getYears();
+        int years2 = age2.getYears();
+
+        Assertions.assertEquals(11, age1.getYears());
+        Assertions.assertEquals(19, age2.getYears());
+        Assertions.assertFalse(pers1.isTeen(years1), "Not teen = false");
+        Assertions.assertFalse(pers2.isTeen(years2), "Not teen = false");
+    }
 
 
     // --- getAge
 
     @Test
-    void getAgeReturns10YearsIfBornIn2009() throws Exception {
+    void getAgeReturns10YearsIfBorn10YearsFromToday() throws Exception {
         // TODO verbessern. Hinweis: Repeatable (wiederholbar) zu jeder Zeit.
-        Person p = new Person("", "", LocalDate.of(2009, 1, 1));
+        Person p = new Person("", "", LocalDate.now().minusYears(10));
 
-        throw new IllegalArgumentException("you should implement code here");
+        //throw new IllegalArgumentException("you should implement code here");
+        Period age = p.getAge();
+        Assertions.assertEquals(10,age.getYears());
+        Assertions.assertEquals(0, age.getMonths());
+        Assertions.assertEquals(0, age.getDays());
     }
 
     @Test
     void getAgeReturns1DayIfYesterday() throws Exception {
         Person p = new Person("", "", LocalDate.now().minusDays(1));
 
         // TODO implement
-        throw new IllegalArgumentException("you should implement code here");
+        //throw new IllegalArgumentException("you should implement code here");
+        Period age = p.getAge();
+        Assertions.assertEquals(1,age.getDays());
+        Assertions.assertEquals(0, age.getMonths());
+        Assertions.assertEquals(0, age.getYears());
     }
 
     // TODO some more useful tests