liming30 commented on code in PR #20405: URL: https://github.com/apache/flink/pull/20405#discussion_r940082838
########## flink-state-backends/flink-statebackend-rocksdb/src/main/java/org/apache/flink/contrib/streaming/state/AbstractRocksDBState.java: ########## @@ -223,4 +223,27 @@ public StateIncrementalVisitor<K, N, V> getStateIncrementalVisitor( throw new UnsupportedOperationException( "Global state entry iterator is unsupported for RocksDb backend"); } + + /** + * Similar to decimal addition, add 1 to the last digit to calculate the upper bound. + * + * @param prefix the starting prefix for seek. + * @return end prefix for seek. + */ + protected final byte[] calculateUpperBound(byte[] prefix) { + byte[] upperBound = new byte[prefix.length]; + System.arraycopy(prefix, 0, upperBound, 0, prefix.length); + boolean overFlow = true; + for (int i = prefix.length - 1; i >= 0; i--) { + int unsignedValue = prefix[i] & 0xff; + int result = unsignedValue + 1; + upperBound[i] = (byte) (result & 0xff); + if (result >> 8 == 0) { + overFlow = false; + break; + } + } + Preconditions.checkArgument(!overFlow, "The upper boundary overflows."); Review Comment: @Myasuka Sorry, I rethought this question, when the `KeyGroup` is 128, the serialized result is `0x80`, and there will be no overflow after adding 1 to the unsigned number. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org