diff -r 5a72ba18c471 -r dda7e13f09fb src/share/classes/com/sun/tools/javac/code/Type.java
--- a/src/share/classes/com/sun/tools/javac/code/Type.java	Mon Aug 31 19:43:06 2009 -0700
+++ b/src/share/classes/com/sun/tools/javac/code/Type.java	Tue Sep 01 14:53:39 2009 +0100
@@ -1068,7 +1068,7 @@
 
         /**
          * Replaces this ForAll's typevars with a set of concrete Java types
-         * and returns the instantiated generic type. Subclasses might override
+         * and returns the instantiated generic type. Subclasses should override
          * in order to check that the list of types is a valid instantiation
          * of the ForAll's typevars.
          *
@@ -1081,6 +1081,42 @@
             return types.subst(qtype, tvars, actuals);
         }
 
+        /**
+         * Kind of type-constraint derived during type inference
+         */
+        public enum ConstraintKind {
+            /**
+             * upper bound constraint (a type variable must be instantiated
+             * with a type T, where T is a subtype of all the types specified by
+             * its EXTENDS constraints).
+             */
+            EXTENDS,
+            /**
+             * lower bound constraint (a type variable must be instantiated
+             * with a type T, where T is a supertype of all the types specified by
+             * its SUPER constraints).
+             */
+            SUPER,
+            /**
+             * equality constraint (a type variable must be instantiated to the type
+             * specified by its EQUAL constraint.
+             */
+            EQUAL;
+        }
+
+        /**
+         * Get the type-constraints of a given kind for a given type-variable of
+         * this ForAll type. Subclasses should override in order to return more
+         * accurate sets of constraints.
+         *
+         * @param tv the type-variable for which the constraint is to be retrieved
+         * @param ck the constraint kind to be retrieved
+         * @return the list of types specified by the selected constraint
+         */
+        public List<Type> getConstraints(TypeVar tv, ConstraintKind ck) {
+            return List.nil();
+        }
+
         public Type map(Mapping f) {
             return f.apply(qtype);
         }