code: public void addExcludedName(String name) {
          Object obj = lookupQualifiedName(scope, name);
          if (!(obj instanceof Scriptable)) {
              throw new IllegalArgumentException("Object for excluded name " +
                                                 name + " not found.");
          }
          table.put(obj, name);
      }
docs: Adds a qualified name to the list of objects to be excluded from
  serialization. Names excluded from serialization are looked up
  in the new scope and replaced upon deserialization.
  @param name a fully qualified name (of the form "a.b.c", where
  "a" must be a property of the top-level object)
  @throws IllegalArgumentException if the object is not found or is not
  a {@link Scriptable}.