diff -r 1a73c6e08cc5 -r d382dacfd73f rt/javap/src/main/java/org/apidesign/javap/StackMapIterator.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/rt/javap/src/main/java/org/apidesign/javap/StackMapIterator.java	Tue Feb 26 16:54:16 2013 +0100
@@ -0,0 +1,179 @@
+/*
+ * Copyright (c) 2012, 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 org.apidesign.javap;
+
+import static org.apidesign.javap.RuntimeConstants.ITEM_Integer;
+import static org.apidesign.javap.RuntimeConstants.ITEM_Float;
+import static org.apidesign.javap.RuntimeConstants.ITEM_Double;
+import static org.apidesign.javap.RuntimeConstants.ITEM_Long;
+import static org.apidesign.javap.RuntimeConstants.ITEM_Object;
+
+public final class StackMapIterator {
+    private final StackMapTableData[] stackMapTable;
+    private final TypeArray argTypes;
+    private final TypeArray localTypes;
+    private final TypeArray stackTypes;
+
+    private int nextFrameIndex;
+    private int lastFrameByteCodeOffset;
+
+    private int byteCodeOffset;
+
+    StackMapIterator(final MethodData methodData) {
+        this(methodData.getStackMapTable(),
+             methodData.getInternalSig(),
+             methodData.isStatic());
+    }
+
+    StackMapIterator(final StackMapTableData[] stackMapTable,
+                     final String methodSignature,
+                     final boolean isStaticMethod) {
+        this.stackMapTable = (stackMapTable != null)
+                                 ? stackMapTable
+                                 : new StackMapTableData[0];
+
+        argTypes = getArgTypes(methodSignature, isStaticMethod);
+        localTypes = new TypeArray();
+        stackTypes = new TypeArray();
+
+        localTypes.addAll(argTypes);
+
+        lastFrameByteCodeOffset = -1;
+        advanceBy(0);
+    }
+
+    public String getFrameAsString() {
+        return (nextFrameIndex == 0)
+                   ? StackMapTableData.toString("INITIAL", 0, null, null)
+                   : stackMapTable[nextFrameIndex - 1].toString();
+    }
+
+    public int getFrameIndex() {
+        return nextFrameIndex;
+    }
+
+    public TypeArray getFrameStack() {
+        return stackTypes;
+    }
+
+    public TypeArray getFrameLocals() {
+        return localTypes;
+    }
+
+    public TypeArray getArguments() {
+        return argTypes;
+    }
+
+    public void advanceBy(final int numByteCodes) {
+        if (numByteCodes < 0) {
+            throw new IllegalStateException("Forward only iterator");
+        }
+
+        byteCodeOffset += numByteCodes;
+        while ((nextFrameIndex < stackMapTable.length)
+                    && ((byteCodeOffset - lastFrameByteCodeOffset)
+                            >= (stackMapTable[nextFrameIndex].offsetDelta
+                                    + 1))) {
+            final StackMapTableData nextFrame = stackMapTable[nextFrameIndex];
+
+            lastFrameByteCodeOffset += nextFrame.offsetDelta + 1;
+            nextFrame.applyTo(localTypes, stackTypes);
+
+            ++nextFrameIndex;
+        }
+    }
+
+    public void advanceTo(final int nextByteCodeOffset) {
+        advanceBy(nextByteCodeOffset - byteCodeOffset);
+    }
+
+    private static TypeArray getArgTypes(final String methodSignature,
+                                         final boolean isStaticMethod) {
+        final TypeArray argTypes = new TypeArray();
+
+        if (!isStaticMethod) {
+            argTypes.add(ITEM_Object);
+        }
+
+        if (methodSignature.charAt(0) != '(') {
+            throw new IllegalArgumentException("Invalid method signature");
+        }
+
+        final int length = methodSignature.length();
+        boolean skipType = false;
+        int argType;
+        for (int i = 1; i < length; ++i) {
+            switch (methodSignature.charAt(i)) {
+                case 'B':
+                case 'C':
+                case 'S':
+                case 'Z':
+                case 'I':
+                    argType = ITEM_Integer;
+                    break;
+                case 'J':
+                    argType = ITEM_Long;
+                    break;
+                case 'F':
+                    argType = ITEM_Float;
+                    break;
+                case 'D':
+                    argType = ITEM_Double;
+                    break;
+                case 'L': {
+                    i = methodSignature.indexOf(';', i + 1);
+                    if (i == -1) {
+                        throw new IllegalArgumentException(
+                                      "Invalid method signature");
+                    }
+                    argType = ITEM_Object;
+                    break;
+                }
+                case ')':
+                    // not interested in the return value type
+                    return argTypes;
+                case '[':
+                    if (!skipType) {
+                        argTypes.add(ITEM_Object);
+                        skipType = true;
+                    }
+                    continue;
+
+                default:
+                    throw new IllegalArgumentException(
+                                  "Invalid method signature");
+            }
+
+            if (!skipType) {
+                argTypes.add(argType);
+            } else {
+                skipType = false;
+            }
+        }
+
+        return argTypes;
+    }
+}