emkornfield commented on a change in pull request #9671: URL: https://github.com/apache/arrow/pull/9671#discussion_r598852516
########## File path: go/parquet/internal/utils/bit_run_reader.go ########## @@ -0,0 +1,146 @@ +// 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 utils + +import ( + "encoding/binary" + "fmt" + "math/bits" + "unsafe" + + "github.com/apache/arrow/go/arrow" + "github.com/apache/arrow/go/arrow/bitutil" +) + +// BitRun represents a run of bits with the same value of length Len +// with Set representing if the group of bits were 1 or 0. +type BitRun struct { + Len int64 + Set bool +} + +// BitRunReader is an interface that is usable by multiple callers to provide +// multiple types of bit run readers such as a reverse reader and so on. +// +// It's a convenience interface for counting contiguous set/unset bits in a bitmap. Review comment: it might be worth commenting that in places where BitBlockCounter can be used that is apreferred method since it will be faster. -- 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. For queries about this service, please contact Infrastructure at: us...@infra.apache.org
