--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.api.interop/src/com/oracle/truffle/api/interop/ForeignAccess.java	Mon Jun 08 04:50:13 2015 +0200
@@ -0,0 +1,288 @@
+/*
+ * Copyright (c) 2014, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.
+ */
+package com.oracle.truffle.api.interop;
+
+import com.oracle.truffle.api.CallTarget;
+import com.oracle.truffle.api.frame.Frame;
+import com.oracle.truffle.api.frame.VirtualFrame;
+import com.oracle.truffle.api.interop.impl.ReadOnlyArrayList;
+import com.oracle.truffle.api.nodes.Node;
+import java.util.List;
+
+/**
+ * Encapsulates types of access to {@link TruffleObject}. If you want to expose your own objects to
+ * foreign language implementations, you need to implement {@link TruffleObject} and its
+ * {@link TruffleObject#getForeignAccess()} method. To create instance of <code>ForeignAccess</code>
+ * , use one of the factory methods available in this class.
+ */
+public final class ForeignAccess {
+    private final Factory factory;
+
+    private ForeignAccess(Factory faf) {
+        this.factory = faf;
+    }
+
+    /**
+     * Creates new instance of {@link ForeignAccess} that delegates to provided factory.
+     *
+     * @param baseClass the super class of all {@link TruffleObject}s handled by this factory (if
+     *            <code>null</code> than the second interface also needs to implement
+     *            {@link Factory})
+     * @param factory the factory that handles access requests to {@link Message}s known as of
+     *            version 1.0
+     * @return new instance wrapping <code>factory</code>
+     */
+    public static ForeignAccess create(final Class<? extends TruffleObject> baseClass, final Factory10 factory) {
+        if (baseClass == null) {
+            Factory f = (Factory) factory;
+            assert f != null;
+        }
+        class DelegatingFactory implements Factory {
+            @Override
+            public boolean canHandle(TruffleObject obj) {
+                if (baseClass == null) {
+                    return ((Factory) factory).canHandle(obj);
+                }
+                return baseClass.isInstance(obj);
+            }
+
+            @Override
+            public CallTarget accessMessage(Message msg) {
+                if (msg instanceof KnownMessage) {
+                    switch (msg.hashCode()) {
+                        case Execute.HASH1:
+                            return factory.accessInvoke(((Execute) msg).getArity());
+                        case Execute.HASH2:
+                            return factory.accessExecute(((Execute) msg).getArity());
+                        case GetSize.HASH:
+                            return factory.accessGetSize();
+                        case HasSize.HASH:
+                            return factory.accessHasSize();
+                        case IsBoxed.HASH:
+                            return factory.accessIsBoxed();
+                        case IsExecutable.HASH:
+                            return factory.accessIsExecutable();
+                        case IsNull.HASH:
+                            return factory.accessIsNull();
+                        case Read.HASH:
+                            return factory.accessRead();
+                        case Unbox.HASH:
+                            return factory.accessUnbox();
+                        case Write.HASH:
+                            return factory.accessWrite();
+                    }
+                }
+                return factory.accessMessage(msg);
+            }
+        }
+        return new ForeignAccess(new DelegatingFactory());
+    }
+
+    /**
+     * Creates new instance of {@link ForeignAccess} that delegates to provided factory.
+     *
+     * @param factory the factory that handles various access requests {@link Message}s.
+     * @return new instance wrapping <code>factory</code>
+     */
+    public static ForeignAccess create(Factory factory) {
+        return new ForeignAccess(factory);
+    }
+
+    /**
+     * Executes {@link Message#createNode() foreign node}.
+     * 
+     * @param foreignNode the createNode created by {@link Message#createNode()}
+     * @param frame the call frame
+     * @param receiver foreign object to receive the message passed to {@link Message#createNode()}
+     *            method
+     * @param arguments parameters for the receiver
+     * @return return value, if any
+     * @throws ClassCastException if the createNode has not been created by
+     *             {@link Message#createNode()} method.
+     */
+    public static Object execute(Node foreignNode, VirtualFrame frame, TruffleObject receiver, Object... arguments) {
+        ForeignObjectAccessHeadNode fn = (ForeignObjectAccessHeadNode) foreignNode;
+        return fn.executeForeign(frame, receiver, arguments);
+    }
+
+    /**
+     * Read only access to foreign call arguments inside of a frame.
+     *
+     * @param frame the frame that was called via
+     *            {@link #execute(com.oracle.truffle.api.nodes.Node, com.oracle.truffle.api.frame.VirtualFrame, com.oracle.truffle.api.interop.TruffleObject, java.lang.Object...) }
+     * @return read-only list of parameters passed to the frame
+     */
+    public static List<Object> getArguments(Frame frame) {
+        final Object[] arr = frame.getArguments();
+        return ReadOnlyArrayList.asList(arr, 1, arr.length);
+    }
+
+    /**
+     * The foreign receiver in the frame.
+     *
+     * @param frame the frame that was called via
+     *            {@link #execute(com.oracle.truffle.api.nodes.Node, com.oracle.truffle.api.frame.VirtualFrame, com.oracle.truffle.api.interop.TruffleObject, java.lang.Object...) }
+     * @return the receiver used when invoking the frame
+     */
+    public static TruffleObject getReceiver(Frame frame) {
+        return (TruffleObject) frame.getArguments()[ForeignAccessArguments.RECEIVER_INDEX];
+    }
+
+    CallTarget access(Message message) {
+        return factory.accessMessage(message);
+    }
+
+    boolean canHandle(TruffleObject receiver) {
+        return factory.canHandle(receiver);
+    }
+
+    /**
+     * Interface of a factory that produces AST snippets that can access a foreign
+     * {@code TruffleObject}. A Truffle language implementation accesses a {@code TruffleObject} via
+     * a {@code Message}. The {@code TruffleObject} instance provides a {@link ForeignAccess}
+     * instance (built via {@link #create(com.oracle.truffle.api.interop.ForeignAccess.Factory)})
+     * that provides an AST snippet for a given {@link Message}. Rather than using this generic
+     * {@code Factory}, consider implementing {@link Factory10} interface that captures the set of
+     * messages each language should implement as of Truffle version 1.0.
+     */
+    public interface Factory {
+
+        /**
+         * * Checks whether provided {@link TruffleObject} can be accessed using AST snippets
+         * produced by this {@link Factory}.
+         *
+         * @param obj the object to check
+         * @return true, if the object can be processed
+         */
+        boolean canHandle(TruffleObject obj);
+
+        /**
+         * Provides an AST snippet to access a {@code TruffleObject}.
+         *
+         * @param tree the {@code Message} that represents the access to a {@code TruffleObject}.
+         * @return the AST snippet for accessing the {@code TruffleObject}, wrapped as a
+         *         {@code CallTarget}.
+         */
+        CallTarget accessMessage(Message tree);
+    }
+
+    /**
+     * Specialized {@link Factory factory} that handles {@link Message messages} known as of release
+     * 1.0 of Truffle API.
+     *
+     */
+    public interface Factory10 {
+        /**
+         * Handles {@link Message#IS_NULL} message.
+         *
+         * @return call target to handle the message or <code>null</code> if this message is not
+         *         supported
+         */
+        CallTarget accessIsNull();
+
+        /**
+         * Handles {@link Message#IS_EXECUTABLE} message.
+         * 
+         * @return call target to handle the message or <code>null</code> if this message is not
+         *         supported
+         */
+        CallTarget accessIsExecutable();
+
+        /**
+         * Handles {@link Message#IS_BOXED} message.
+         * 
+         * @return call target to handle the message or <code>null</code> if this message is not
+         *         supported
+         */
+        CallTarget accessIsBoxed();
+
+        /**
+         * Handles {@link Message#HAS_SIZE} message.
+         * 
+         * @return call target to handle the message or <code>null</code> if this message is not
+         *         supported
+         */
+        CallTarget accessHasSize();
+
+        /**
+         * Handles {@link Message#GET_SIZE} message.
+         * 
+         * @return call target to handle the message or <code>null</code> if this message is not
+         *         supported
+         */
+        CallTarget accessGetSize();
+
+        /**
+         * Handles {@link Message#UNBOX} message.
+         * 
+         * @return call target to handle the message or <code>null</code> if this message is not
+         *         supported
+         */
+        CallTarget accessUnbox();
+
+        /**
+         * Handles {@link Message#READ} message.
+         * 
+         * @return call target to handle the message or <code>null</code> if this message is not
+         *         supported
+         */
+        CallTarget accessRead();
+
+        /**
+         * Handles {@link Message#WRITE} message.
+         * 
+         * @return call target to handle the message or <code>null</code> if this message is not
+         *         supported
+         */
+        CallTarget accessWrite();
+
+        /**
+         * Handles {@link Message#createExecute(int)} messages.
+         * 
+         * @param argumentsLength number of parameters the messages has been created for
+         * @return call target to handle the message or <code>null</code> if this message is not
+         *         supported
+         */
+        CallTarget accessExecute(int argumentsLength);
+
+        /**
+         * Handles {@link Message#createInvoke(int)} messages.
+         * 
+         * @param argumentsLength number of parameters the messages has been created for
+         * @return call target to handle the message or <code>null</code> if this message is not
+         *         supported
+         */
+        CallTarget accessInvoke(int argumentsLength);
+
+        /**
+         * Handles request for access to a message not known in version 1.0.
+         *
+         * @param unknown the message
+         * @return call target to handle the message or <code>null</code> if this message is not
+         *         supported
+         */
+        CallTarget accessMessage(Message unknown);
+    }
+}