public KafkaFuture<Void> all() {
        final KafkaFutureImpl<Void> result = new KafkaFutureImpl<>();

        this.future.whenComplete((topicPartitions, throwable) -> {
            if (throwable != null) {
                result.completeExceptionally(throwable);
            } else {
                for (TopicPartition partition : partitions) {
                    if (maybeCompleteExceptionally(topicPartitions, partition, result)) {
                        return;
                    }
                }
                result.complete(null);
            }
        });
        return result;
    }
Return a future which succeeds only if all the deletions succeed.
If not, the first partition error shall be returned.
clients/src/main/java/org/apache/kafka/clients/admin/DeleteConsumerGroupOffsetsResult.java