Update Java STM API to include STM utils

akka-stm/src/test/java/akka/stm/example/EitherOrElseExample.java

@@ -0,0 +1,27 @@
+package akka.stm.example;
+
+import akka.stm.*;
+import akka.actor.*;
+
+public class EitherOrElseExample {
+    public static void main(String[] args) {
+        System.out.println();
+        System.out.println("EitherOrElse example");
+        System.out.println();
+
+        final Ref<Integer> left = new Ref<Integer>(100);
+        final Ref<Integer> right = new Ref<Integer>(100);
+
+        ActorRef brancher = Actors.actorOf(Brancher.class).start();
+
+        brancher.sendOneWay(new Branch(left, right, 500));
+
+        new Atomic() {
+            public Object atomically() {
+                return right.set(right.get() + 1000);
+            }
+        }.execute();
+
+        brancher.stop();
+    }
+}