ssage_ = value;           }           onChanged();         } else {           nestedMessageBuilder_.mergeFrom(value);         }          return this;       }       /**        * <code>.io.confluent.kafka.serializers.protobuf.test.NestedMessage nested_message = 0;</code>        */       public Builder clearNestedMessage() {         if (nestedMessageBuilder_ == null) {           nestedMessage_ = null;           onChanged();         } else {           nestedMessage_ = null;           nestedMessageBuilder_ = null;         }          return this;       }       /**        * <code>.io.confluent.kafka.serializers.protobuf.test.NestedMessage nested_message = 0;</code>        */       public io.confluent.kafka.serializers.protobuf.test.NestedTestProto.NestedMessage.Builder 