private void initTsFileAnalysed()

in tsfile-viewer-core/src/main/java/org/apache/iotdb/tool/core/service/TsFileAnalyserV13.java [127:292]
69 lines of code
15 McCabe index (conditional complexity)

  private void initTsFileAnalysed() throws IOException {

    ChunkMetadata currentChunk;
    String measurementID;
    TSDataType dataType;
    long fileOffsetOfChunk;

    // ChunkMetadata of current ChunkGroup
    List<IChunkMetadata> chunkMetadataList = new ArrayList<>();
    List<List<ChunkHeader>> chunkHeaderLists = new ArrayList<>();

    long headerLength = TSFileConfig.MAGIC_STRING.getBytes().length + Byte.BYTES;

    reader.position(headerLength);

    byte marker;
    List<long[]> timeBatch = new ArrayList<>();
    String lastDeviceId = null;
    long lastChunkGroupPosition = 0;

    //    List<IMeasurementSchema> measurementSchemaList = new ArrayList<>();
    IChunkMetadata alignedTimeChunk = null;
    List<IChunkMetadata> alignedValueChunk = new ArrayList<>();
    List<ChunkHeader> chunkHeaderList = new ArrayList<>();
    // 0 NonAligned, 1 TimeColumn, 2 ValueColumn
    int alignedFlag = 0;
    try {
      while ((marker = reader.readMarker()) != MetaMarker.SEPARATOR) {
        switch (marker) {
          case MetaMarker.CHUNK_HEADER:
          case MetaMarker.TIME_CHUNK_HEADER:
          case MetaMarker.VALUE_CHUNK_HEADER:
          case MetaMarker.ONLY_ONE_PAGE_CHUNK_HEADER:
          case MetaMarker.ONLY_ONE_PAGE_TIME_CHUNK_HEADER:
          case MetaMarker.ONLY_ONE_PAGE_VALUE_CHUNK_HEADER:
            ChunkHeader chunkHeader = reader.readChunkHeader(marker);
            chunkHeaderList.add(chunkHeader);
            // 跳过此 chunk，已经读取了 chunkHeader，直接加 dataSize 即可
            reader.position(reader.position() + chunkHeader.getDataSize());
            // 更新进度条
            setRateOfProcess();
            break;

          case MetaMarker.CHUNK_GROUP_HEADER:
            // if there is something wrong with the ChunkGroup Header, we will drop this ChunkGroup
            // because we can not guarantee the correctness of the deviceId.
            logger.info("Starting read a new ChunkGroupHeader, lastDeviceId:{}", lastDeviceId);
            // 更新进度条
            setRateOfProcess();
            //            lastChunkGroupPosition = reader.position();
            if (lastDeviceId != null) {
              // schema of last chunk group
              //              for (IMeasurementSchema tsSchema : measurementSchemaList) {
              //                newSchema.putIfAbsent(
              //                    new Path(lastDeviceId, tsSchema.getMeasurementId()), tsSchema);
              //              }
              //              measurementSchemaList = new ArrayList<>();

              // 存储上一个 ChunkGroup 已读取的信息
              //              if (alignedTimeChunk != null && alignedValueChunk.size() > 0) {
              //                chunkMetadataList.add(
              //                    new AlignedChunkMetadata(alignedTimeChunk, new
              // ArrayList<>(alignedValueChunk)));
              //                chunkHeaderLists.add(new ArrayList<>(chunkHeaderList));
              //                alignedValueChunk.clear();
              //                chunkHeaderList.clear();
              //              }
              //              chunkGroupMetadataModelList.add(
              //                  new ChunkGroupMetadataModel(
              //                      lastDeviceId,
              //                      new ArrayList<>(chunkMetadataList),
              //                      new ArrayList<>(chunkHeaderLists)));
              //              chunkMetadataList.clear();
              //              chunkHeaderLists.clear();

              chunkGroupInfoList.add(new ChunkGroupInfo(lastDeviceId, lastChunkGroupPosition));
            }

            // this is a chunk group
            //            lastChunkGroupPosition = reader.position() - 1;
            lastChunkGroupPosition = reader.position();
            //            chunkMetadataList = new ArrayList<>();
            ChunkGroupHeader chunkGroupHeader = reader.readChunkGroupHeader();
            lastDeviceId = chunkGroupHeader.getDeviceID();
            break;
            // plan index: 标记 chunkgroup 的结束（可用于类似断点续传、checkPoint、snapshot等）
          case MetaMarker.OPERATION_INDEX_RANGE:
            logger.info("Starting read OperationIndexRange, lastDeviceId:{}", lastDeviceId);
            setRateOfProcess();
            if (lastDeviceId != null) {
              // schema of last chunk group
              //              for (IMeasurementSchema tsSchema : measurementSchemaList) {
              //                newSchema.putIfAbsent(
              //                    new Path(lastDeviceId, tsSchema.getMeasurementId()), tsSchema);
              //              }
              //              measurementSchemaList = new ArrayList<>();
              //              if (alignedTimeChunk != null && alignedValueChunk.size() > 0) {
              //                chunkMetadataList.add(
              //                    new AlignedChunkMetadata(alignedTimeChunk, new
              // ArrayList<>(alignedValueChunk)));
              //                chunkHeaderLists.add(new ArrayList<>(chunkHeaderList));
              //                alignedValueChunk.clear();
              //                chunkHeaderList.clear();
              //              }
              //              // last chunk group Metadata
              //              chunkGroupMetadataModelList.add(
              //                  new ChunkGroupMetadataModel(
              //                      lastDeviceId,
              //                      new ArrayList<>(chunkMetadataList), // 不需要
              //                      new ArrayList<>(chunkHeaderLists))); // 需要
              //              chunkMetadataList.clear();
              //              chunkHeaderLists.clear();

              chunkGroupInfoList.add(new ChunkGroupInfo(lastDeviceId, lastChunkGroupPosition));

              lastDeviceId = null;
              lastChunkGroupPosition = -1;
            }
            reader.readPlanIndex();
            break;
          default:
            // the disk file is corrupted, using this file may be dangerous
            logger.error("Unexpected marker:{}", marker);
            throw new IOException("Unexpected marker " + marker);
        }
      }

      // now we read the tail of the data section, so we are sure that the last
      // ChunkGroupFooter is complete.
      if (lastDeviceId != null && lastChunkGroupPosition != -1) {
        logger.info("Read the tail of the data section, the lastDeviceId:{}", lastDeviceId);
        setRateOfProcess();

        chunkGroupInfoList.add(new ChunkGroupInfo(lastDeviceId, lastChunkGroupPosition));

        // schema of last chunk group
        //        for (IMeasurementSchema tsSchema : measurementSchemaList) {
        //          newSchema.putIfAbsent(new Path(lastDeviceId, tsSchema.getMeasurementId()),
        // tsSchema);
        //        }
        //        if (alignedTimeChunk != null && alignedValueChunk.size() > 0) {
        //          chunkMetadataList.add(
        //              new AlignedChunkMetadata(alignedTimeChunk, new
        // ArrayList<>(alignedValueChunk)));
        //          chunkHeaderLists.add(new ArrayList<>(chunkHeaderList));
        //          alignedValueChunk.clear();
        //          chunkHeaderList.clear();
        //        }
        // last chunk group Metadata
        //        chunkGroupMetadataModelList.add(
        //            new ChunkGroupMetadataModel(
        //                lastDeviceId,
        //                new ArrayList<>(chunkMetadataList),
        //                new ArrayList<>(chunkHeaderLists)));
        //        chunkMetadataList.clear();
        //        chunkHeaderLists.clear();
      }

    } catch (Exception e) {
      logger.warn(
          "TsFile {} self-check cannot proceed at position {}, recovered, because : {}",
          filePath,
          reader.position(),
          e.getMessage());
    }
  }