Scan/Reduce Fix

Author: Jon Schneider

src/main/java/learnrxjava/ObservableExercises.java

@@ -38,7 +38,7 @@ public Observable<String> exerciseFilterMap(Observable<Integer> nums) {
     /**
      * Flatten out all video in the stream of Movies into a stream of videoIDs
      * 
-     * @param movieLists
+     * @param movies
      * @return Observable of Integers of Movies.videos.id
      */
     public Observable<Integer> exerciseConcatMap(Observable<Movies> movies) {
@@ -55,7 +55,7 @@ public Observable<Integer> exerciseConcatMap(Observable<Movies> movies) {
      * 
      * We'll see more about this later when we add concurrency.
      * 
-     * @param movieLists
+     * @param movies
      * @return Observable of Integers of Movies.videos.id
      */
     public Observable<Integer> exerciseFlatMap(Observable<Movies> movies) {

src/main/java/learnrxjava/examples/ScanVsReduceExample.java

@@ -5,16 +5,22 @@
 import rx.Observable;
 
 public class ScanVsReduceExample {
-
     public static void main(String... args) {
+        System.out.println("reduce ...");
         Observable.range(0, 10).reduce(new ArrayList<>(), (list, i) -> {
             list.add(i);
             return list;
         }).forEach(System.out::println);
 
-        System.out.println("... vs ...");
+        System.out.println("... vs collect ...");
+
+        Observable.range(0, 10).collect(() -> new ArrayList<>(), (list, i) -> {
+            list.add(i);
+        }).forEach(System.out::println);
+
+        System.out.println("... vs scan ...");
 
-        Observable.range(0, 10).scan(new ArrayList<>(), (list, i) -> {
+        Observable.range(0, 10).scan(new ArrayList<Integer>(), (list, i) -> {
             list.add(i);
             return list;
         }).forEach(System.out::println);