--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.object/src/com/oracle/truffle/object/Transition.java	Tue Nov 18 23:19:43 2014 +0100
@@ -0,0 +1,144 @@
+/*
+ * Copyright (c) 2013, 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.
+ *
+ * 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.object;
+
+import java.util.*;
+
+import com.oracle.truffle.api.object.*;
+
+public abstract class Transition {
+    @Override
+    public int hashCode() {
+        int result = 1;
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj == null) {
+            return false;
+        }
+        if (getClass() != obj.getClass()) {
+            return false;
+        }
+        return true;
+    }
+
+    public abstract static class PropertyTransition extends Transition {
+        private final Property property;
+
+        public PropertyTransition(Property property) {
+            this.property = property;
+        }
+
+        @Override
+        public int hashCode() {
+            final int prime = 31;
+            int result = super.hashCode();
+            result = prime * result + ((property == null) ? 0 : property.hashCode());
+            return result;
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (!super.equals(obj)) {
+                return false;
+            }
+            PropertyTransition other = (PropertyTransition) obj;
+            if (!Objects.equals(property, other.property)) {
+                return false;
+            }
+            return true;
+        }
+
+        public Property getProperty() {
+            return property;
+        }
+    }
+
+    public static final class AddTransition extends PropertyTransition {
+        public AddTransition(Property property) {
+            super(property);
+        }
+    }
+
+    public static final class RemoveTransition extends PropertyTransition {
+        public RemoveTransition(Property property) {
+            super(property);
+        }
+    }
+
+    public static final class OperationsTransition extends Transition {
+        private final ObjectType operations;
+
+        public OperationsTransition(ObjectType operations) {
+            this.operations = operations;
+        }
+
+        public ObjectType getOperations() {
+            return operations;
+        }
+
+        @Override
+        public boolean equals(Object other) {
+            return super.equals(other) && Objects.equals(operations, ((OperationsTransition) other).operations);
+        }
+
+        @Override
+        public int hashCode() {
+            final int prime = 31;
+            int result = super.hashCode();
+            result = prime * result + ((operations == null) ? 0 : operations.hashCode());
+            return result;
+        }
+    }
+
+    public static final class TypeTransition extends PropertyTransition {
+        private final Property after;
+
+        public TypeTransition(Property before, Property after) {
+            super(before);
+            this.after = after;
+        }
+
+        public Property getPropertyBefore() {
+            return this.getProperty();
+        }
+
+        public Property getPropertyAfter() {
+            return after;
+        }
+    }
+
+    public static final class ReservePrimitiveArrayTransition extends Transition {
+        public ReservePrimitiveArrayTransition() {
+        }
+    }
+
+    public String getShortName() {
+        return this.getClass().getSimpleName().replaceFirst("Transition$", "").toLowerCase();
+    }
+}