public Builder addAllJoints(
          java.lang.Iterable<? extends org.box2d.proto.Box2D.PbJoint> values) {
        if (jointsBuilder_ == null) {
          ensureJointsIsMutable();
          super.addAll(values, joints_);
          onChanged();
        } else {
          jointsBuilder_.addAllMessages(values);
        }
        return this;
      }