code: public java.lang.String getSelector() {
      java.lang.Object ref = selector_;
      if (ref instanceof java.lang.String) {
        return (java.lang.String) ref;
      } else {
        com.google.protobuf.ByteString bs = 
            (com.google.protobuf.ByteString) ref;
        java.lang.String s = bs.toStringUtf8();
        selector_ = s;
        return s;
      }
    }
docs: <pre>
  The selector is a comma-separated list of patterns. Each pattern is a
  qualified name of the element which may end in "*", indicating a wildcard.
  Wildcards are only allowed at the end and for a whole component of the
  qualified name, i.e. "foo.*" is ok, but not "foo.b*" or "foo.*.bar". To
  specify a default for all applicable elements, the whole pattern "*"
  is used.
  </pre>
  
  <code>string selector = 1;</code>