Fixed javadocs

tests/samples-messaging-camel/src/main/java/com/example/BookService.java

@@ -31,7 +31,8 @@ public class BookService {
 	 * Scenario for "should generate tests triggered by a method": client side: must have
 	 * a possibility to "trigger" sending of a message to the given messageFrom server
 	 * side: will run the method and await upon receiving message on the output
-	 * messageFrom. Method triggers sending a message to a source
+	 * messageFrom. Method triggers sending a message to a source.
+	 * @param exchange - input exchange.
 	 */
 	public void returnBook(Exchange exchange) {
 		BookReturned bookReturned = exchange.getIn().getBody(BookReturned.class);