--- a/langtools/src/share/classes/com/sun/tools/javac/jvm/ClassReader.java	Mon Aug 20 13:50:04 2012 -0700
+++ b/langtools/src/share/classes/com/sun/tools/javac/jvm/ClassReader.java	Mon Aug 27 07:21:46 2012 -0700
@@ -188,7 +188,7 @@
 
     /** The current input pointer.
      */
-    int bp;
+    protected int bp;
 
     /** The objects of the constant pool.
      */
@@ -890,13 +890,13 @@
 
     protected enum AttributeKind { CLASS, MEMBER };
     protected abstract class AttributeReader {
-        AttributeReader(Name name, ClassFile.Version version, Set<AttributeKind> kinds) {
+        protected AttributeReader(Name name, ClassFile.Version version, Set<AttributeKind> kinds) {
             this.name = name;
             this.version = version;
             this.kinds = kinds;
         }
 
-        boolean accepts(AttributeKind kind) {
+        protected boolean accepts(AttributeKind kind) {
             if (kinds.contains(kind)) {
                 if (majorVersion > version.major || (majorVersion == version.major && minorVersion >= version.minor))
                     return true;
@@ -915,11 +915,11 @@
             return false;
         }
 
-        abstract void read(Symbol sym, int attrLen);
+        protected abstract void read(Symbol sym, int attrLen);
 
-        final Name name;
-        final ClassFile.Version version;
-        final Set<AttributeKind> kinds;
+        protected final Name name;
+        protected final ClassFile.Version version;
+        protected final Set<AttributeKind> kinds;
     }
 
     protected Set<AttributeKind> CLASS_ATTRIBUTE =
@@ -936,7 +936,7 @@
             // v45.3 attributes
 
             new AttributeReader(names.Code, V45_3, MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     if (readAllOfClassFile || saveParameterNames)
                         ((MethodSymbol)sym).code = readCode(sym);
                     else
@@ -945,7 +945,7 @@
             },
 
             new AttributeReader(names.ConstantValue, V45_3, MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     Object v = readPool(nextChar());
                     // Ignore ConstantValue attribute if field not final.
                     if ((sym.flags() & FINAL) != 0)
@@ -954,13 +954,13 @@
             },
 
             new AttributeReader(names.Deprecated, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     sym.flags_field |= DEPRECATED;
                 }
             },
 
             new AttributeReader(names.Exceptions, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     int nexceptions = nextChar();
                     List<Type> thrown = List.nil();
                     for (int j = 0; j < nexceptions; j++)
@@ -971,14 +971,14 @@
             },
 
             new AttributeReader(names.InnerClasses, V45_3, CLASS_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     ClassSymbol c = (ClassSymbol) sym;
                     readInnerClasses(c);
                 }
             },
 
             new AttributeReader(names.LocalVariableTable, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     int newbp = bp + attrLen;
                     if (saveParameterNames) {
                         // Pick up parameter names from the variable table.
@@ -1014,7 +1014,7 @@
             },
 
             new AttributeReader(names.SourceFile, V45_3, CLASS_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     ClassSymbol c = (ClassSymbol) sym;
                     Name n = readName(nextChar());
                     c.sourcefile = new SourceFileObject(n, c.flatname);
@@ -1022,7 +1022,7 @@
             },
 
             new AttributeReader(names.Synthetic, V45_3, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     // bridge methods are visible when generics not enabled
                     if (allowGenerics || (sym.flags_field & BRIDGE) == 0)
                         sym.flags_field |= SYNTHETIC;
@@ -1032,7 +1032,7 @@
             // standard v49 attributes
 
             new AttributeReader(names.EnclosingMethod, V49, CLASS_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     int newbp = bp + attrLen;
                     readEnclosingMethodAttr(sym);
                     bp = newbp;
@@ -1041,11 +1041,11 @@
 
             new AttributeReader(names.Signature, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
                 @Override
-                boolean accepts(AttributeKind kind) {
+                protected boolean accepts(AttributeKind kind) {
                     return super.accepts(kind) && allowGenerics;
                 }
 
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     if (sym.kind == TYP) {
                         ClassSymbol c = (ClassSymbol) sym;
                         readingClassAttr = true;
@@ -1074,31 +1074,31 @@
             // v49 annotation attributes
 
             new AttributeReader(names.AnnotationDefault, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     attachAnnotationDefault(sym);
                 }
             },
 
             new AttributeReader(names.RuntimeInvisibleAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     attachAnnotations(sym);
                 }
             },
 
             new AttributeReader(names.RuntimeInvisibleParameterAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     attachParameterAnnotations(sym);
                 }
             },
 
             new AttributeReader(names.RuntimeVisibleAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     attachAnnotations(sym);
                 }
             },
 
             new AttributeReader(names.RuntimeVisibleParameterAnnotations, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     attachParameterAnnotations(sym);
                 }
             },
@@ -1106,14 +1106,14 @@
             // additional "legacy" v49 attributes, superceded by flags
 
             new AttributeReader(names.Annotation, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     if (allowAnnotations)
                         sym.flags_field |= ANNOTATION;
                 }
             },
 
             new AttributeReader(names.Bridge, V49, MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     sym.flags_field |= BRIDGE;
                     if (!allowGenerics)
                         sym.flags_field &= ~SYNTHETIC;
@@ -1121,13 +1121,13 @@
             },
 
             new AttributeReader(names.Enum, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     sym.flags_field |= ENUM;
                 }
             },
 
             new AttributeReader(names.Varargs, V49, CLASS_OR_MEMBER_ATTRIBUTE) {
-                void read(Symbol sym, int attrLen) {
+                protected void read(Symbol sym, int attrLen) {
                     if (allowVarargs)
                         sym.flags_field |= VARARGS;
                 }
@@ -1153,7 +1153,7 @@
 
 
 
-    void readEnclosingMethodAttr(Symbol sym) {
+    protected void readEnclosingMethodAttr(Symbol sym) {
         // sym is a nested class with an "Enclosing Method" attribute
         // remove sym from it's current owners scope and place it in
         // the scope specified by the attribute

--- a/langtools/src/share/classes/com/sun/tools/javac/jvm/ClassWriter.java	Mon Aug 20 13:50:04 2012 -0700
+++ b/langtools/src/share/classes/com/sun/tools/javac/jvm/ClassWriter.java	Mon Aug 27 07:21:46 2012 -0700
@@ -164,7 +164,7 @@
 
     /** Construct a class writer, given an options table.
      */
-    private ClassWriter(Context context) {
+    protected ClassWriter(Context context) {
         context.put(classWriterKey, this);
 
         log = Log.instance(context);
@@ -601,12 +601,20 @@
      *  Returns the number of attributes written (0 or 1).
      */
     int writeEnclosingMethodAttribute(ClassSymbol c) {
-        if (!target.hasEnclosingMethodAttribute() ||
-            c.owner.kind != MTH && // neither a local class
+        if (!target.hasEnclosingMethodAttribute())
+            return 0;
+        return writeEnclosingMethodAttribute(names.EnclosingMethod, c);
+    }
+
+    /** Write the EnclosingMethod attribute with a specified name.
+     *  Returns the number of attributes written (0 or 1).
+     */
+    protected int writeEnclosingMethodAttribute(Name attributeName, ClassSymbol c) {
+        if (c.owner.kind != MTH && // neither a local class
             c.name != names.empty) // nor anonymous
             return 0;
 
-        int alenIdx = writeAttr(names.EnclosingMethod);
+        int alenIdx = writeAttr(attributeName);
         ClassSymbol enclClass = c.owner.enclClass();
         MethodSymbol enclMethod =
             (c.owner.type == null // local to init block
@@ -1569,6 +1577,7 @@
         acount += writeFlagAttrs(c.flags());
         acount += writeJavaAnnotations(c.getAnnotationMirrors());
         acount += writeEnclosingMethodAttribute(c);
+        acount += writeExtraClassAttributes(c);
 
         poolbuf.appendInt(JAVA_MAGIC);
         poolbuf.appendChar(target.minorVersion);
@@ -1588,6 +1597,14 @@
         pool = c.pool = null; // to conserve space
      }
 
+    /**Allows subclasses to write additional class attributes
+     *
+     * @return the number of attributes written
+     */
+    protected int writeExtraClassAttributes(ClassSymbol c) {
+        return 0;
+    }
+
     int adjustFlags(final long flags) {
         int result = (int)flags;
         if ((flags & SYNTHETIC) != 0  && !target.useSyntheticFlag())