--- /dev/null	2017-03-16 11:03:49.895616831 -0700
+++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.graphio/src/org/graalvm/graphio/GraphElements.java	2017-08-03 22:43:01.211897847 -0700
@@ -0,0 +1,198 @@
+/*
+ * Copyright (c) 2011, 2017, 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 org.graalvm.graphio;
+
+/**
+ * Representation of methods, fields, their signatures and code locations.
+ *
+ * @param <M> type representing methods
+ * @param <F> type representing fields
+ * @param <S> type representing signature
+ * @param <P> type representing source code location
+ */
+public interface GraphElements<M, F, S, P> {
+    /**
+     * Recognize method. Can the object be seen as a method?
+     *
+     * @param obj the object to check
+     * @return <code>null</code> if the object isn't a method, non-null value otherwise
+     */
+    M method(Object obj);
+
+    /**
+     * Bytecode for a method.
+     *
+     * @param method the method
+     * @return bytecode of the method
+     */
+    byte[] methodCode(M method);
+
+    /**
+     * Method modifiers.
+     *
+     * @param method the method
+     * @return its modifiers
+     */
+    int methodModifiers(M method);
+
+    /**
+     * Method's signature.
+     *
+     * @param method the method
+     * @return signature of the method
+     */
+    S methodSignature(M method);
+
+    /**
+     * Method name.
+     *
+     * @param method the method
+     * @return name of the method
+     */
+    String methodName(M method);
+
+    /**
+     * Method's declaring class. The returned object shall be a {@link Class} or be recognizable by
+     * {@link GraphTypes#typeName(java.lang.Object)} method.
+     *
+     * @param method the method
+     * @return object representing class that defined the method
+     */
+    Object methodDeclaringClass(M method);
+
+    /**
+     * Recognizes a field. Can the object be seen as a field?
+     *
+     * @param object the object to check
+     * @return <code>null</code> if the object isn't a field, non-null value otherwise
+     */
+    F field(Object object);
+
+    /**
+     * Field modifiers.
+     *
+     * @param field the field
+     * @return field modifiers
+     */
+    int fieldModifiers(F field);
+
+    /**
+     * Type name of the field.
+     *
+     * @param field the field
+     * @return the name of the field's type
+     */
+    String fieldTypeName(F field);
+
+    /**
+     * Name of a field.
+     *
+     * @param field the field
+     * @return the name of the field
+     */
+    String fieldName(F field);
+
+    /**
+     * Field's declaring class. The returned object shall be a {@link Class} or be recognizable by
+     * {@link GraphTypes#typeName(java.lang.Object)} method.
+     *
+     * @param field the field
+     * @return object representing class that defined the field
+     */
+    Object fieldDeclaringClass(F field);
+
+    /**
+     * Recognizes signature. Can the object be seen as a signature?
+     *
+     * @param object the object to check
+     * @return <code>null</code> if the object isn't a signature, non-null value otherwise
+     */
+    S signature(Object object);
+
+    /**
+     * Number of parameters of a signature.
+     *
+     * @param signature the signature
+     * @return number of parameters
+     */
+    int signatureParameterCount(S signature);
+
+    /**
+     * Type name of a signature parameter.
+     *
+     * @param signature the signature
+     * @param index index from 0 to {@link #signatureParameterCount(java.lang.Object)} - 1
+     * @return the type name
+     */
+    String signatureParameterTypeName(S signature, int index);
+
+    /**
+     * Type name of a return type.
+     *
+     * @param signature the signature
+     * @return the type name
+     */
+    String signatureReturnTypeName(S signature);
+
+    /**
+     * Recognize a source position. Can the object be seen as a position?
+     *
+     * @param object the object to check
+     * @return <code>null</code> if the object isn't a position, non-null otherwise
+     */
+    P nodeSourcePosition(Object object);
+
+    /**
+     * Method for a position.
+     *
+     * @param pos the position
+     * @return the method at the position
+     */
+    M nodeSourcePositionMethod(P pos);
+
+    /**
+     * Caller of a position.
+     *
+     * @param pos the position
+     * @return <code>null</code> or another position
+     */
+    P nodeSourcePositionCaller(P pos);
+
+    /**
+     * Byte code index of a position.
+     *
+     * @param pos the position
+     * @return the BCI of the position
+     */
+    int nodeSourcePositionBCI(P pos);
+
+    /**
+     * Stack trace element for a method, index and position.
+     *
+     * @param method the method
+     * @param bci the index
+     * @param pos the position
+     * @return stack trace element for the method, index and position
+     */
+    StackTraceElement methodStackTraceElement(M method, int bci, P pos);
+}