organized, added futures

src/generator/future/Future.java

@@ -0,0 +1,18 @@
+package generator.future;
+
+public interface Future<R> {
+
+    @SuppressWarnings("unchecked")
+    default R poll(Waker waker){
+        return (R) Pending.INSTANCE;
+    }
+
+    default R await(){
+        throw new RuntimeException();
+    }
+
+    final class Pending{
+        private static final Pending INSTANCE = new Pending();
+        private Pending(){}
+    }
+}