Add untyped transactor

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

@@ -0,0 +1,25 @@
+package akka.stm.example;
+
+import akka.stm.*;
+
+public class CounterExample {
+    final static Ref<Integer> ref = new Ref<Integer>(0);
+
+    public static int counter() {
+        return new Atomic<Integer>() {
+            public Integer atomically() {
+                int inc = ref.get() + 1;
+                ref.set(inc);
+                return inc;
+            }
+        }.execute();
+    }
+
+    public static void main(String[] args) {
+        System.out.println();
+        System.out.println("Counter example");
+        System.out.println();
+        System.out.println("counter 1: " + counter());
+        System.out.println("counter 2: " + counter());
+    }
+}