From 9406bce795fc2043ecc7477c52e271a0fa2ae857 Mon Sep 17 00:00:00 2001
From: MenTaLguY <mental@rydia.net>
Date: Mon, 23 Jul 2007 08:21:05 -0400
Subject: [PATCH] non-blocking thunks for Java

---
 java/concurrent/FuturesService.java | 40 ++++++++++++++++---------------------
 1 file changed, 17 insertions(+), 23 deletions(-)

diff --git a/java/concurrent/FuturesService.java b/java/concurrent/FuturesService.java
index 13cff10..bc3b5ca 100644
--- a/java/concurrent/FuturesService.java
+++ b/java/concurrent/FuturesService.java
@@ -49,8 +49,8 @@ public class FuturesService implements BasicLibraryService {
     }
 
     public static class Thunk extends RubyObject {
-        private IRubyObject source;
-        private IRubyObject value;
+        private volatile IRubyObject source;
+        private volatile IRubyObject value;
 
         Thunk(Ruby runtime, RubyClass klass, IRubyObject source) {
             super(runtime, klass, false);
@@ -78,27 +78,23 @@ public class FuturesService implements BasicLibraryService {
             while (obj instanceof Thunk) {
                 Thunk thunk=(Thunk)obj;
 
-                synchronized (thunk) {
-                    if ( thunk.source != null ) {
-                        if (evaluate) {
-                            thunk.value = thunk.source.callMethod(thunk.source.getRuntime().getCurrentContext(), "value");
-                            thunk.source = null;
-                        }
-
-                        if ( obj != original ) {
-                            Thunk original_thunk = (Thunk)original;
-                            synchronized (original_thunk) {
-                                original_thunk.value = thunk.value;
-                            }
-                        }
-
-                        if (!evaluate) {
-                            break;
-                        }
+                if ( thunk.value == null ) {
+                    if (evaluate) {
+                        thunk.value = thunk.source.callMethod(thunk.source.getRuntime().getCurrentContext(), "value");
+                        thunk.source = null;
                     }
 
-                    obj = thunk.value;
+                    if ( obj != original ) {
+                        Thunk original_thunk = (Thunk)original;
+                        original_thunk.value = thunk.value;
+                    }
+
+                    if (!evaluate) {
+                        break;
+                    }
                 }
+
+                obj = thunk.value;
             }
 
             return obj;
@@ -130,9 +126,7 @@ public class FuturesService implements BasicLibraryService {
                 if ( name == "inspect" && args.length == 1 ) {
                     Thunk thunk = (Thunk)self;
                     IRubyObject source;
-                    synchronized (thunk) {
-                        source = thunk.source;
-                    }
+                    source = thunk.source;
                     if ( source != null ) {
                         Ruby runtime = getRuntime();
                         return runtime.newString("#<Thunk " + source.callMethod(runtime.getCurrentContext(), "inspect").asString().toString() + ">");
-- 
2.11.4.GIT