basic filtering examples

Author: MWhyte

java-cookbook/readme.md

@@ -1,6 +1,6 @@
 # java cookbook
 
-Sample code for article [@codenerve.com](https://www.codenerve.com/) #TODO update link
+Sample code for article [@codenerve.com](https://www.codenerve.com/java-streams-cookbook/)
 
 ## Contents
 - Basic operations on lists

java-cookbook/src/test/java/com/codenerve/streams/lists/ListFiltering.java

@@ -4,6 +4,7 @@
 import org.junit.jupiter.api.Test;
 
 import java.util.List;
+import java.util.Optional;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
@@ -69,6 +70,15 @@ void filter_pattern_books() {
         assertThat(fiveStarBooks.size(), is(equalTo(3)));
     }
 
+    @Test
+    void find_a_robert_martin_book() {
+        Optional<Book> aRobertMartinBook = books.stream()
+                .filter(book -> book.getAuthor().contains("Martin Fowler"))
+                .findAny();
+
+        assertThat(aRobertMartinBook.get().getAuthor(), is(equalTo("Martin Fowler")));
+    }
+
     @Test
     void find_a_martin_fowler_book() {
         Book aMartinFowlerBook = books.stream()