maedhroz commented on code in PR #2267: URL: https://github.com/apache/cassandra/pull/2267#discussion_r1167181166
########## src/java/org/apache/cassandra/io/sstable/format/bti/RowIndexReverseIterator.java: ########## @@ -0,0 +1,70 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.cassandra.io.sstable.format.bti; + +import java.io.PrintStream; + +import org.apache.cassandra.io.sstable.format.bti.RowIndexReader.IndexInfo; +import org.apache.cassandra.io.tries.ReverseValueIterator; +import org.apache.cassandra.io.util.FileHandle; +import org.apache.cassandra.utils.bytecomparable.ByteComparable; + +/** + * Reverse iterator over the row index. Needed to get previous index blocks for reverse iteration. + */ +class RowIndexReverseIterator extends ReverseValueIterator<RowIndexReverseIterator> +{ + private long currentNode = -1; + + public RowIndexReverseIterator(FileHandle file, long root, ByteComparable start, ByteComparable end) + { + super(file.instantiateRebufferer(null), root, start, end, true); + } + + public RowIndexReverseIterator(FileHandle file, TrieIndexEntry entry, ByteComparable end) + { + this(file, entry.indexTrieRoot, ByteComparable.EMPTY, end); + } + + /** + * This method must be async-read-safe. + */ + public IndexInfo nextIndexInfo() + { + if (currentNode == -1) + { + currentNode = nextPayloadedNode(); + if (currentNode == -1) + return null; + } + + go(currentNode); + IndexInfo info = RowIndexReader.readPayload(buf, payloadPosition(), payloadFlags()); + + currentNode = -1; + return info; + } + + public void dumpTrie(PrintStream out) + { + dumpTrie(out, (buf, ppos, bits) -> { + IndexInfo ii = RowIndexReader.readPayload(buf, ppos, bits); Review Comment: nit: I guess `readPayload()` could return null here and cause problems -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
