--- a/nashorn/src/jdk/nashorn/internal/runtime/linker/JavaAdapterBytecodeGenerator.java	Wed May 15 12:09:38 2013 -0300
+++ b/nashorn/src/jdk/nashorn/internal/runtime/linker/JavaAdapterBytecodeGenerator.java	Wed May 15 20:21:59 2013 +0200
@@ -310,7 +310,34 @@
                 Type.getMethodDescriptor(Type.VOID_TYPE), null, null));
 
         mv.invokestatic(SERVICES_CLASS_TYPE_NAME, "getClassOverrides", GET_CLASS_INITIALIZER_DESCRIPTOR);
-        // Assign MethodHandle fields through invoking getHandle()
+        final Label initGlobal;
+        if(samName != null) {
+            // If the class is a SAM, allow having a ScriptFunction passed as class overrides
+            final Label notAFunction = new Label();
+            mv.dup();
+            mv.instanceOf(SCRIPT_FUNCTION_TYPE);
+            mv.ifeq(notAFunction);
+            mv.checkcast(SCRIPT_FUNCTION_TYPE);
+
+            // Assign MethodHandle fields through invoking getHandle() for a ScriptFunction, only assigning the SAM
+            // method(s).
+            for (final MethodInfo mi : methodInfos) {
+                if(mi.getName().equals(samName)) {
+                    mv.dup();
+                    mv.aconst(Type.getMethodType(mi.type.toMethodDescriptorString()));
+                    mv.invokestatic(SERVICES_CLASS_TYPE_NAME, "getHandle", GET_HANDLE_FUNCTION_DESCRIPTOR);
+                } else {
+                    mv.visitInsn(ACONST_NULL);
+                }
+                mv.putstatic(generatedClassName, mi.methodHandleClassFieldName, METHOD_HANDLE_TYPE_DESCRIPTOR);
+            }
+            initGlobal = new Label();
+            mv.goTo(initGlobal);
+            mv.visitLabel(notAFunction);
+        } else {
+            initGlobal = null;
+        }
+        // Assign MethodHandle fields through invoking getHandle() for a ScriptObject
         for (final MethodInfo mi : methodInfos) {
             mv.dup();
             mv.aconst(mi.getName());
@@ -319,6 +346,9 @@
             mv.putstatic(generatedClassName, mi.methodHandleClassFieldName, METHOD_HANDLE_TYPE_DESCRIPTOR);
         }
 
+        if(initGlobal != null) {
+            mv.visitLabel(initGlobal);
+        }
         // Assign "staticGlobal = Context.getGlobal()"
         invokeGetGlobalWithNullCheck(mv);
         mv.putstatic(generatedClassName, STATIC_GLOBAL_FIELD_NAME, SCRIPT_OBJECT_TYPE_DESCRIPTOR);

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nashorn/test/script/basic/JDK-8014647.js	Wed May 15 20:21:59 2013 +0200
@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * 
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ * 
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ * 
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ * 
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * JDK-8014647: Allow class-based overrides to be initialized with a ScriptFunction
+ *
+ * @test
+ * @run
+ */
+
+var RunnableImpl1 = Java.extend(java.lang.Runnable, function() { print("I'm runnable 1!") })
+var RunnableImpl2 = Java.extend(java.lang.Runnable, function() { print("I'm runnable 2!") })
+var r1 = new RunnableImpl1()
+var r2 = new RunnableImpl2()
+var r3 = new RunnableImpl2(function() { print("I'm runnable 3!") })
+r1.run()
+r2.run()
+r3.run()
+print("r1.class === r2.class: " + (r1.class === r2.class))
+print("r2.class === r3.class: " + (r2.class === r3.class))

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nashorn/test/script/basic/JDK-8014647.js.EXPECTED	Wed May 15 20:21:59 2013 +0200
@@ -0,0 +1,5 @@
+I'm runnable 1!
+I'm runnable 2!
+I'm runnable 3!
+r1.class === r2.class: false
+r2.class === r3.class: true