diff --git a/src/test/java/lambda/part2/exercise/ArrowNotationExercise.java b/src/test/java/lambda/part2/exercise/ArrowNotationExercise.java index c43edc4..6a47139 100644 --- a/src/test/java/lambda/part2/exercise/ArrowNotationExercise.java +++ b/src/test/java/lambda/part2/exercise/ArrowNotationExercise.java @@ -14,35 +14,49 @@ public class ArrowNotationExercise { @Test public void getAge() { // Person -> Integer - final Function getAge = null; // TODO + final Function getAge = Person::getAge; // TODO assertEquals(Integer.valueOf(33), getAge.apply(new Person("", "", 33))); } + private static boolean sameAges(Person p1, Person p2) { + return p1.getAge() == p2.getAge(); + } + @Test public void compareAges() { // TODO use BiPredicate // compareAges: (Person, Person) -> boolean + final BiPredicate compareAges = ArrowNotationExercise::sameAges; + - throw new UnsupportedOperationException("Not implemented"); - //assertEquals(true, compareAges.test(new Person("a", "b", 22), new Person("c", "d", 22))); + //throw new UnsupportedOperationException("Not implemented"); + assertEquals(true, compareAges.test(new Person("a", "b", 22), new Person("c", "d", 22))); } // TODO // getFullName: Person -> String - + private String getFullName(Person p) { + return p.getFirstName() + " " + p.getLastName(); + } // TODO - // ageOfPersonWithTheLongestFullName: (Person -> String) -> (Person, Person) -> int + // ageOfPersonWithTheLongestFullName: (Person -> String) => ((Person, Person) -> int) // + private BiFunction ageOfPersonWithLongestFullName(Function fullName) { + return (Person p1, Person p2) -> fullName.apply(p1).length() > fullName.apply(p2).length() + ? p1.getAge() + : p2.getAge(); + } @Test public void getAgeOfPersonWithTheLongestFullName() { // Person -> String - final Function getFullName = null; // TODO + final Function getFullName = this::getFullName; // TODO // (Person, Person) -> Integer // TODO use ageOfPersonWithTheLongestFullName(getFullName) - final BiFunction ageOfPersonWithTheLongestFullName = null; + final BiFunction ageOfPersonWithTheLongestFullName = + ageOfPersonWithLongestFullName(getFullName); assertEquals( Integer.valueOf(1), diff --git a/src/test/java/lambda/part2/exercise/FunctionCombinationExercise.java b/src/test/java/lambda/part2/exercise/FunctionCombinationExercise.java index ce7080f..1de00bd 100644 --- a/src/test/java/lambda/part2/exercise/FunctionCombinationExercise.java +++ b/src/test/java/lambda/part2/exercise/FunctionCombinationExercise.java @@ -19,22 +19,14 @@ public void personHasNotEmptyLastNameAndFirstName0() { assertEquals(false, validate.test(new Person("a", "", 0))); } - // TODO // negate1: (Person -> boolean) -> (Person -> boolean) private Predicate negate1(Predicate test) { - return p -> { - // TODO - throw new UnsupportedOperationException(); - }; + return p -> !test.test(p); } - // TODO // validateFirstNameAndLastName: (Person -> boolean, Person -> boolean) -> (Person -> boolean) private Predicate validateFirstNameAndLastName(Predicate t1, Predicate t2) { - return p -> { - // TODO - throw new UnsupportedOperationException(); - }; + return p -> t1.test(p) && t2.test(p); } @Test @@ -52,18 +44,14 @@ public void personHasNotEmptyLastNameAndFirstName1() { assertEquals(false, validate.test(new Person("a", "", 0))); } - // TODO // negate: (T -> boolean) -> (T -> boolean) private Predicate negate(Predicate test) { - // TODO - throw new UnsupportedOperationException(); + return T -> !test.test(T); } - // TODO // and: (T -> boolean, T -> boolean) -> (T -> boolean) private Predicate and(Predicate t1, Predicate t2) { - // TODO - throw new UnsupportedOperationException(); + return T -> t1.test(T) && (t2.test(T)); } @Test @@ -71,10 +59,10 @@ public void personHasNotEmptyLastNameAndFirstName2() { final Predicate hasEmptyFirstName = p -> p.getFirstName().isEmpty(); final Predicate hasEmptyLastName = p -> p.getLastName().isEmpty(); - final Predicate validateFirstName = null; // TODO use negate - final Predicate validateLastName = null; // TODO use negate + final Predicate validateFirstName = negate(hasEmptyFirstName); // TODO use negate + final Predicate validateLastName = negate(hasEmptyLastName); // TODO use negate - final Predicate validate = null; // TODO use and + final Predicate validate = validateFirstName.and(validateLastName); // TODO use and assertEquals(true, validate.test(new Person("a", "b", 0))); assertEquals(false, validate.test(new Person("", "b", 0))); @@ -86,10 +74,10 @@ public void personHasNotEmptyLastNameAndFirstName3() { final Predicate hasEmptyFirstName = p -> p.getFirstName().isEmpty(); final Predicate hasEmptyLastName = p -> p.getLastName().isEmpty(); - final Predicate validateFirstName = null; // TODO use Predicate::negate - final Predicate validateLastName = null; // TODO use Predicate::negate + final Predicate validateFirstName = hasEmptyFirstName.negate(); // TODO use Predicate::negate + final Predicate validateLastName = hasEmptyLastName.negate(); // TODO use Predicate::negate - final Predicate validate = null; // TODO use Predicate::and + final Predicate validate = validateFirstName.and(validateLastName); // TODO use Predicate::and assertEquals(true, validate.test(new Person("a", "b", 0))); assertEquals(false, validate.test(new Person("", "b", 0)));