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Streams and assertion libraries. (Using APIs).

1. Streaming Persons

In the sheets you find a variant of the code below

print rhymes with aal
void method() {
  List<Person> personList = new ArrayList<>();
  personList.add(new Person("John Doe", 15));
  personList.add(new Person("Jane Doe", 17));
  personList.add(new Person("Anne Modaal", 35));
  personList.add(new Person("Max Modaal", 19));
  personList.add(new Person("Tom Generaal", 53));
  personList.add(new Person("Erika Modaal", 28));

  personList
    .stream()                         (1)
    .map(Person::getName)             (2)
    .map(String::toLowerCase)         (3)
    .filter(s -> s.endsWith("aal"))   (4)
    .forEach(System.out::println);    (5)
}
1 Stream the collection.
2 turn it into a stream of names
3 make it lower. You could combine 2 and 3.
4 select only the ones matching
5 pull the stream (terminal op) and print each that comes out.

Question. What is the stream Type after 1 and what after 2?

Make a version that computes the average age of the daals. (If you did not guess it yet: the numbers are the ages.).
Use streams of course.

2. CSV2Objects

3. Lambda Library

The start project is a maven project for easy integration of the test framework AssertJ.