// streams/StreamOfOptionals.java

// (c)2017 MindView LLC: see Copyright.txt

// We make no guarantees that this code is fit for any purpose.

// Visit http://OnJava8.com for more book information.

import java.util.*;

import java.util.stream.*;

public class StreamOfOptionals {

public static void main(String[] args) {

Signal.stream()

.limit(10)

.forEach(System.out::println);

System.out.println(" ---");

Signal.stream()

.limit(10)

.filter(Optional::isPresent)

.map(Optional::get)

.forEach(System.out::println);

}

}

/* Output:

Optional[Signal(dash)]

Optional[Signal(dot)]

Optional[Signal(dash)]

Optional.empty

Optional.empty

Optional[Signal(dash)]

Optional.empty

Optional[Signal(dot)]

Optional[Signal(dash)]

Optional[Signal(dash)]

---

Signal(dot)

Signal(dot)

Signal(dash)

Signal(dash)

*/