From ac434d48525a0e5b57c66b9f61b388ccf3d898b5 Mon Sep 17 00:00:00 2001
From: Hiram Chirino <hiram@hiramchirino.com>
Date: Wed, 18 Jul 2012 14:55:50 -0400
Subject: [PATCH] Adding support for transforming functions into Callable
 objects and integration with ExecutorService.

---
 libraries/stdlib/src/kotlin/Standard.kt        | 11 +++++++++++
 .../stdlib/src/kotlin/concurrent/Thread.kt     | 18 ++++++++++++++++++
 libraries/stdlib/test/concurrent/ThreadTest.kt | 10 ++++++++++
 3 files changed, 39 insertions(+)

diff --git a/libraries/stdlib/src/kotlin/Standard.kt b/libraries/stdlib/src/kotlin/Standard.kt
index 3d100aa6b5d..9d5e3328847 100644
--- a/libraries/stdlib/src/kotlin/Standard.kt
+++ b/libraries/stdlib/src/kotlin/Standard.kt
@@ -4,6 +4,7 @@ import java.util.ArrayList
 import java.util.Collection
 import java.util.HashSet
 import java.util.LinkedList
+import java.util.concurrent.Callable
 
 /**
 Helper to make jet.Iterator usable in for
@@ -77,3 +78,13 @@ public inline fun runnable(action: ()-> Unit): Runnable {
         }
     }
 }
+
+/**
+ * A helper method for creating a [[Callable]] from a function
+ */
+public inline fun <T> callable(action: ()-> T): Callable<T> {
+    return object: Callable<T> {
+        public override fun call() = action()
+    }
+}
+
diff --git a/libraries/stdlib/src/kotlin/concurrent/Thread.kt b/libraries/stdlib/src/kotlin/concurrent/Thread.kt
index f0d6e8ce956..0c12a2dfc1a 100644
--- a/libraries/stdlib/src/kotlin/concurrent/Thread.kt
+++ b/libraries/stdlib/src/kotlin/concurrent/Thread.kt
@@ -1,6 +1,9 @@
 package kotlin.concurrent
 
 import java.util.concurrent.Executor
+import java.util.concurrent.ExecutorService
+import java.util.concurrent.Future
+import java.util.concurrent.Callable
 
 inline val currentThread : Thread
     get() = Thread.currentThread().sure()
@@ -58,3 +61,18 @@ public inline fun Executor.invoke(action: ()->Unit) {
     execute(runnable(action))
 }
 
+/**
+ * Executes the given block on the [[Executor]]
+ */
+public inline fun <T>ExecutorService.submit(action: ()->T):Future<T> {
+    val c:Callable<T> = callable(action)
+    return submit(c).sure();
+}
+
+/**
+* Allows you to use the executor as a function to
+* execute the given block on the [[Executor]].
+*/
+public inline fun <T>ExecutorService.invoke(action: ()->T):Future<T> {
+    return submit(action)
+}
\ No newline at end of file
diff --git a/libraries/stdlib/test/concurrent/ThreadTest.kt b/libraries/stdlib/test/concurrent/ThreadTest.kt
index af40e7f7200..54bab4576ae 100644
--- a/libraries/stdlib/test/concurrent/ThreadTest.kt
+++ b/libraries/stdlib/test/concurrent/ThreadTest.kt
@@ -18,4 +18,14 @@ class ThreadTest {
         }
         assertTrue(countDown.await(2, SECONDS), "Count down is executed")
     }
+
+    test fun callableInvoke() {
+
+        val pool = Executors.newFixedThreadPool(1).sure()
+        val future = pool<String> {
+            "Hello"
+        }
+        assertEquals("Hello", future.get(2, SECONDS))
+    }
+
 }
\ No newline at end of file